CN103346848B - A kind of method and apparatus of noise measuring - Google Patents

Abstract

Embodiments of the present invention provide a method and device for noise detection, which relate to the field of communication, so as to realize accurate detection of signal noise. The method includes: the noise detection device acquires the subcarriers in the orthogonal frequency division multiplexing OFDM symbol to be detected power value of the subcarrier, and determine the identity of the subcarrier set corresponding to the subcarrier, and obtain the corresponding noise detection threshold value according to the identity of the subcarrier set, and determine the power value of the subcarrier according to the noise detection threshold value to satisfy When using a noise detection strategy, it is determined that the subcarrier has noise, and this embodiment of the present invention is used for noise detection.

Description

Method and device for noise detection

technical field

The present invention relates to the communication field, in particular to a noise detection method and equipment.

Background technique

In the PLC (Power Line Communication, power line communication) system, narrow-band noise interference is a relatively common interference. In order to ensure the normal transmission of the signal, it is necessary to eliminate or reduce the interference of the noise to the signal, and before eliminating or reducing the interference of the noise to the signal , it is necessary to detect whether there is noise in the signal.

In the prior art, the ratio of the power value of the subcarrier to the average power value of all subcarriers corresponding to the OFDM (Orthogonal Frequency Division Multiplexing, Orthogonal Frequency Division Multiplexing, Orthogonal Frequency Division Multiplexing) symbol to be detected and the preset The threshold value is compared, and if it is determined that the ratio is greater than or equal to the preset threshold value, it is determined that the subcarrier has noise. However, for the noise detection of signals in deep fading channels in the frequency domain, the existing noise detection technology is too simple. Causes false detection and missed detection of noise, thereby affecting signal transmission.

Contents of the invention

Embodiments of the present invention provide a method and device for detecting noise, so as to realize accurate detection of signal noise.

In order to achieve the above object, embodiments of the present invention adopt the following technical solutions:

In the first aspect, a method for noise detection is provided, including:

The noise detection device obtains the power value of the subcarrier in the orthogonal frequency division multiplexing OFDM symbol to be detected;

Determine the identity of the subcarrier set corresponding to the subcarrier, and obtain the corresponding noise detection threshold value according to the identity of the subcarrier set; wherein, the subcarrier set is the A set determined according to a preset number of elements in subcarriers in an OFDM symbol;

When it is determined according to the noise detection threshold that the power value of the subcarrier satisfies a noise detection strategy, it is determined that the subcarrier has noise.

In the first possible implementation manner of the first aspect, before determining the identity of the subcarrier set corresponding to the subcarrier, the method further includes:

The set of subcarriers is determined from the subcarriers in the OFDM symbol to be detected according to a preset number of elements.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation manner, the acquiring the power value of the subcarrier in the OFDM symbol to be detected by the noise detection device includes:

Determining a sample OFDM symbol from the received OFDM symbol, wherein the sample OFDM symbol is a sample symbol determined for obtaining a power value of a subcarrier in the OFDM symbol to be detected;

According to the sample OFDM symbol passing formula:

$\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}$

Obtain the power value of the subcarrier in the OFDM symbol to be detected; Wherein, P(n) is the power value of the subcarrier in the OFDM symbol to be detected, M is the quantity of the sample OFDM symbol, and m is The identifier of the sample OFDM symbol, n is the identifier of the subcarrier, r _{m, n} is the nth subcarrier in the mth sample OFDM symbol.

With reference to the second possible implementation manner, in a third possible implementation manner, the determination of the identity of the subcarrier set corresponding to the subcarrier, and obtaining the corresponding noise detection threshold according to the identity of the subcarrier set Values include:

The first average power value is obtained by the ratio of the sum of the power values of all subcarriers in the subcarrier set corresponding to the identifier of the subcarrier set to the number of subcarriers in the subcarrier set, wherein the first average The power value is the average power value of the subcarriers in the subcarrier set;

determining a maximum power value from power values of subcarriers within the set of subcarriers;

A detection threshold is obtained according to the first average power value and the maximum power value.

With reference to the third possible implementation manner, in a fourth possible implementation manner, the obtaining the noise detection threshold value according to the first average power value and the maximum power value includes:

A first detection threshold value is obtained according to the first average power value: wherein, the first detection threshold value is: A· _Pa (d-1)

A second detection threshold value is obtained according to the first average power value: wherein, the second detection threshold value is: A·P _a (d+1)

A third detection threshold value is obtained according to the first average power value: wherein, the third detection threshold value is: A·P _a (d)

A fourth detection threshold value is obtained according to the maximum power value: wherein, the fourth detection threshold value is:

Wherein, d is the identifier of the subcarrier set, P _a (d) is the first average power value, P _a (d+1) is the average power value of the subcarriers in the d+1th subcarrier set, and P _a (d-1) is the average power value of the subcarriers in the d-1th subcarrier set, P _m (d) is the maximum power value among the power values of the subcarriers in the subcarrier set, A is the first preset parameter, B is the second preset parameter.

With reference to the fourth possible implementation manner, in a fifth possible implementation manner, before determining that the subcarrier has noise, the method further includes:

By formula:

Determine the number of subcarrier sets from the subcarriers in the OFDM symbols to be detected according to the preset number of elements, where W is the number of the subcarrier sets, and N is the number of subcarriers in the OFDM symbols to be detected. The number of subcarriers, NS is the preset number of elements;

By formula:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; W</span>}}\underset{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>$

Obtain a second average power value; wherein, the P _t is the second average power, P _a (d) is the first average power value, d is the identity of the subcarrier set, and W is the subcarrier set The number of carrier sets, the second average power value is an average power value obtained from the average power value of subcarriers in all subcarrier sets in the OFDM symbol to be detected;

When determining that the power value of the subcarrier satisfies the noise detection strategy according to the noise detection threshold value, determining that there is noise in the subcarrier includes:

When it is determined that the power value of the subcarrier is greater than or equal to the first detection threshold value, adding 1 to the preset variable value, where the initial value of the preset variable value is 0;

When it is determined that the power value of the subcarrier is greater than or equal to the second detection threshold value, adding 1 to the preset variable value;

When it is determined that the power value of the subcarrier is greater than or equal to the third detection threshold and greater than or equal to the fourth detection threshold, add 1 to the preset variable value;

When it is determined that the preset variable value is greater than 1 and the second average power value is greater than or equal to a preset power threshold value, it is determined that the subcarrier has noise.

With reference to the fifth possible implementation manner, in a sixth possible implementation manner, after determining that the power value of the subcarrier is less than the third detection threshold value, and/or determining that the power value of the subcarrier is less than When the fourth detection threshold value is reached, the preset variable value is cleared to zero.

With reference to the fifth possible implementation manner or the sixth possible implementation manner, in a seventh possible implementation manner, after determining that the subcarrier has noise, the method further includes:

Continue to determine whether the power value of the next subcarrier in the OFDM symbol to be detected meets the noise detection strategy; wherein the next subcarrier includes the subcarrier corresponding to the identifier obtained by adding one to the identifier of the subcarrier;

When the power values of the subcarriers whose preset values are continuously determined do not satisfy the noise detection strategy, determine a noise detection result, wherein the noise detection result includes an identifier corresponding to a subcarrier that satisfies the noise detection strategy.

In a second aspect, a noise detection device is provided, including:

An acquisition unit, configured to acquire the power value of the subcarrier in the orthogonal frequency division multiplexing OFDM symbol to be detected;

a processing unit, configured to determine an identifier of a subcarrier set corresponding to the subcarrier, obtain a corresponding noise detection threshold value according to the identifier of the subcarrier set, and determine the acquired When the power value of the subcarrier obtained by the unit satisfies the noise detection strategy, it is determined that the subcarrier has noise; wherein the subcarrier set is the noise detection device from the subcarriers in the OFDM symbol to be detected according to the preset Set a set with a certain number of elements.

In the first possible implementation manner of the second aspect, the processing unit is further configured to, before determining the identity of the subcarrier set corresponding to the subcarrier, from the subcarriers in the OFDM symbol to be detected The set of subcarriers is determined according to the preset number of elements.

With reference to the second aspect or the first possible implementation manner, in a second possible implementation manner, the obtaining unit is specifically configured to determine sample OFDM symbols from received OFDM symbols, where the sample OFDM symbols are Used to obtain the sample symbol determined by the power value of the subcarrier in the OFDM symbol to be detected;

According to the sample OFDM symbol passing formula:

$\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}$

Obtain the power value of the subcarrier in the OFDM symbol to be detected; Wherein, P(n) is the power value of the subcarrier in the OFDM symbol to be detected, M is the quantity of the sample OFDM symbol, and m is The identifier of the sample OFDM symbol, n is the identifier of the subcarrier, r _{m, n} is the nth subcarrier in the mth sample OFDM symbol.

With reference to the second possible implementation manner, in a third possible implementation manner, the processing unit is specifically configured to combine the sum of the power values of all subcarriers in the subcarrier set corresponding to the identifier of the subcarrier set with The first average power value is obtained from the ratio of the number of subcarriers in the subcarrier set, the maximum power value is determined from the power values of the subcarriers in the subcarrier set, and according to the first average power value and the maximum A detection threshold value is obtained as a power value, wherein the first average power value is an average power value of subcarriers in the subcarrier set.

With reference to the third possible implementation manner, in a fourth possible implementation manner, the processing unit is specifically configured to obtain a first detection threshold value according to the first average power value: wherein, the first detection threshold value The threshold value is: A·P _a (d-1)

A second detection threshold value is obtained according to the first average power value: wherein, the second detection threshold value is: A·P _a (d+1)

A third detection threshold value is obtained according to the first average power value: wherein, the third detection threshold value is: A·P _a (d)

A fourth detection threshold value is obtained according to the maximum power value: wherein, the fourth detection threshold value is:

Wherein, d is the identifier of the subcarrier set, P _a (d) is the first average power value, P _a (d+1) is the average power value of the subcarriers in the d+1th subcarrier set, and P _a (d-1) is the average power value of the subcarriers in the d-1th subcarrier set, P _m (d) is the maximum power value among the power values of the subcarriers in the subcarrier set, A is the first preset parameter, B is the second preset parameter.

With reference to the fourth possible implementation manner, in a fifth possible implementation manner, the processing unit is further configured to, before determining that the subcarrier has noise, use a formula:

Determine the number of subcarrier sets from the subcarriers in the OFDM symbols to be detected according to the preset number of elements, where W is the number of the subcarrier sets, and N is the number of subcarriers in the OFDM symbols to be detected. The number of subcarriers, NS is the preset number of elements;

By formula:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; W</span>}}\underset{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>$

Obtain a second average power value; wherein, the P _t is the second average power, P _a (d) is the first average power value, d is the identity of the subcarrier set, and W is the subcarrier set The number of carrier sets, the second average power value is an average power value obtained from the average power value of subcarriers in all subcarrier sets in the OFDM symbol to be detected;

The processing unit is specifically configured to, when it is determined that the power value of the subcarrier is greater than or equal to the first detection threshold value, add 1 to the preset variable value, wherein the initial value of the preset variable value is is 0;

When it is determined that the power value of the subcarrier is greater than or equal to the second detection threshold value, adding 1 to the preset variable value;

When it is determined that the power value of the subcarrier is greater than or equal to the third detection threshold value and greater than or equal to the fourth detection threshold value, adding 1 to the preset variable value;

When it is determined that the preset variable value is greater than 1 and the second average power value is greater than or equal to a preset power threshold value, it is determined that the subcarrier has noise.

With reference to the fifth possible implementation manner, in a sixth possible implementation manner, the processing unit is further configured to determine that the power value of the subcarrier is less than the third detection threshold, and/or determine When the power value of the subcarrier is smaller than the fourth detection threshold value, the preset variable value is cleared to zero.

With reference to the fifth possible implementation manner or the sixth possible implementation manner, in a seventh possible implementation manner, the processing unit is further configured to continue to determine the pending Whether the power value of the next subcarrier in the detected OFDM symbol satisfies the noise detection strategy, and when the power value of the subcarrier with the preset value is determined continuously does not satisfy the noise detection strategy, determine the noise detection result, wherein the noise detection result It includes an identifier corresponding to a subcarrier satisfying the noise detection strategy, and the next subcarrier includes a subcarrier corresponding to an identifier obtained by adding one to the identifier of the subcarrier.

By adopting the above scheme, the noise detection device obtains the power value of the subcarrier in the orthogonal frequency division multiplexing OFDM symbol to be detected, determines the identity of the subcarrier set corresponding to the subcarrier, and obtains the corresponding The noise detection threshold value of the noise detection threshold value, when the power value of the subcarrier is determined to meet the noise detection strategy according to the noise detection threshold value, it is determined that the subcarrier has noise. In this way, the OFDM symbols to be detected are divided into sets, and for each set A more accurate noise detection strategy is adopted to enable accurate detection of signal noise even in channel fading scenarios to ensure reliable signal transmission.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a schematic diagram of a noise detection method provided by an embodiment of the present invention;

FIG. 2 is a schematic flowchart of a noise detection method provided by an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a noise detection device provided by an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of another noise detection device provided by an embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

An embodiment of the present invention provides a method for noise detection, as shown in Figure 1, the execution subject of the method is a noise detection device, and the method includes:

S101. The noise detection device acquires a power value of a subcarrier in an OFDM symbol to be detected.

Specifically, the noise detection device determines a sample OFDM symbol from the received OFDM symbol, wherein the sample OFDM symbol is a sample symbol determined for obtaining the power value of the subcarrier in the OFDM symbol to be detected, and according to the sample OFDM symbol By formula:

$\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}$

Obtain the power value of the subcarrier in the OFDM symbol to be detected; wherein, P(n) is the power value of the subcarrier in the OFDM symbol to be detected, M is the number of the sample OFDM symbols, and m is the sample OFDM Symbol identifier, n is the identifier of the subcarrier, r _m,n is the nth subcarrier in the mth sample OFDM symbol.

It can be seen from the above formula that the calculation of the power value of the subcarriers in the OFDM symbol to be detected is to add the power values of the subcarriers corresponding to the same subcarrier identifier in each sample OFDM symbol, and obtain the sum obtained after the addition Value and the ratio of the number of sample OFDM symbols, so as to obtain the power value of the subcarrier corresponding to the subcarrier identifier in the OFDM symbol to be detected, for example, the noise detection device receives 4 OFDM symbols, and selects 2 sample OFDM symbol, then add the power values of the subcarriers marked as 0 in the 2 sample OFDM symbols, and add the value obtained after the addition to the number of sample OFDM symbols (that is, the 2 OFDM symbols selected above) By comparing, the power value of the subcarrier with the subcarrier identifier of 0 in the OFDM symbol to be detected is obtained, and the subcarrier identifier in the OFDM symbol to be detected is 1 to the maximum value corresponding to the subcarrier identifier. The power values of the subcarriers, so as to obtain the power values of all the subcarriers in the to-be-detected OFDM symbol; this is just an example and not limited.

It should be noted that, for noise that exists for a long time, the more the number of sample OFDM symbols is determined, the more accurate the power value of the subcarriers in the OFDM symbol to be detected is, and the detection of subsequent noise is more accurate. However, Since the more sample OFDM symbols are selected, the delay of noise detection will be higher, and the complexity of calculation will be higher, which will cause the burden of system operation. Therefore, for the noise that exists for a long time, the determined sample OFDM symbols need to consider The burden of running the system. For bursty noise, it is necessary to detect the noise as soon as possible, so under the condition that the noise can be detected, the fewer determined sample OFDM symbols, the better.

In addition, the above identifier of the subcarrier may be a label of the subcarrier, for example, the subcarriers in the OFDM symbol may be labeled in the order of 0, 1, 2 . . . .

S102. The noise detection device determines an identifier of a subcarrier set corresponding to the subcarrier, and obtains a corresponding noise detection threshold according to the identifier of the subcarrier set.

Wherein, the subcarrier set is a set determined by the noise detection device according to a preset number of elements from the subcarriers in the OFDM symbol to be detected.

Specifically, the noise detection device determines the subcarrier set from the subcarriers in the OFDM symbol to be detected according to the preset number of elements, for example, if the preset number of elements is 5, then the subcarriers in the OFDM symbol to be detected Taking 5 as a set, if there are 10 subcarriers in the OFDM symbol, divide the 10 subcarriers into two sets.

Optionally, the identification of the subcarriers in each subcarrier set divided by the noise detection device may be continuous, for example, the OFDM symbol to be detected includes 10 subcarriers, and the labels are respectively marked as 0, 1, 2... ...9, and divided into 2 sets according to the preset number of elements being 5, and the labels are marked as 0 and 1 respectively, wherein, the set labeled 0 includes subcarriers labeled 0 to 4, and the set labeled 1 includes Subcarriers numbered 5 to 9. Of course, the identification of the subcarriers in each subcarrier set can also be discontinuous, such as taking the subcarriers marked as 0, 2, 4, 6 and 8 as a set, and the subcarriers marked as 1, 3, 5, 7 and 9 As a set, the present invention is not limited thereto.

In addition, if the determined number of preset elements cannot guarantee the average division of the subcarriers in the OFDM symbol, after determining the set of subcarriers, divide the remaining subcarriers into the determined set of subcarriers, for example, if the number of preset elements is 3, if there are 10 subcarriers in the OFDM symbol, divide the 10 subcarriers into 3 sets according to the preset number of elements, and at this time, if there is 1 subcarrier left, then divide the subcarriers into the above 3 sets in any of them.

It should be noted that the determined subcarrier set includes an identifier of the subcarrier set, for example, may be a label of the subcarrier set, such as labeling in the order of 0, 1, 2 . . . .

Further, the noise detection device obtains the first average power value from the ratio of the sum of the power values of all subcarriers in the subcarrier set corresponding to the identity of the subcarrier set to the number of subcarriers in the subcarrier set, and obtains the first average power value from the A maximum power value is determined from the power values of the subcarriers in the subcarrier set, and a detection threshold is obtained according to the first average power value and the maximum power value.

Wherein, the first average power value is an average power value of subcarriers in the subcarrier set.

Specifically, the noise detection device obtains the first detection threshold according to the first average power value

A·P _a (d-1)

Value: Wherein, the first detection threshold value is:

The noise detection device obtains a second detection threshold value according to the first average power value: wherein, the second detection threshold value is: A·P _a (d+1)

The noise detection device obtains a third detection threshold value according to the first average power value: wherein, the third detection threshold value is: A·P _a (d)

The noise detection device obtains a fourth detection threshold value according to the maximum power value: wherein, the fourth detection threshold value is:

Wherein, d is the identity of the subcarrier set, P _a (d) is the first average power value, P _a (d+1) is the average power value of subcarriers in the d+1th subcarrier set, P _a (d -1) is the average power value of the subcarriers in the d-1th subcarrier set, P _m (d) is the maximum power value among the power values of the subcarriers in the subcarrier set, A is the first preset parameter, and B is the first preset parameter Two preset parameters.

S103. The noise detection device determines that there is noise in the subcarrier when it is determined according to the noise detection threshold that the power value of the subcarrier satisfies the noise detection strategy.

Specifically, before the step S103, the noise detection device uses the formula:

Determine the number of subcarrier sets from the subcarriers in the OFDM symbol to be detected according to the preset number of elements, where W is the number of the subcarrier set, and N is the number of subcarriers in the OFDM symbol to be detected , NS is the preset number of elements,

It can be seen from the formula that W is valued according to the principle of rounding down.

The noise detection equipment passes the formula:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; W</span>}}\underset{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>$

Obtain the second average power value; wherein, the P _{t is} the second average power, P _a (d) is the first average power value, d is the identity of the subcarrier set, W is the number of the subcarrier set, The second average power value is an average power value obtained from average power values of subcarriers in all subcarrier sets in the OFDM symbol to be detected.

Further, when the noise detection device determines that the power value of the subcarrier satisfies the noise detection strategy according to the noise detection threshold value, determining that the subcarrier has noise specifically includes the following four steps:

Step 1. When the noise detection device determines that the power value of the subcarrier is greater than or equal to the first detection threshold value, it adds 1 to the preset variable value.

Wherein, the initial value of the preset variable value is 0.

Step 2: When the noise detection device determines that the power value of the subcarrier is greater than or equal to the second detection threshold value, add 1 to the preset variable value.

It should be noted that the implementation order of step 1 and step 2 is not limited, and step 2 may be performed first, and then step 1 may be performed.

Step 3: When the noise detection device determines that the power value of the subcarrier is greater than or equal to the third detection threshold and greater than or equal to the fourth detection threshold, add 1 to the preset variable value.

Further, when the noise detection device determines that the power value of the subcarrier is less than the third detection threshold value, and/or determines that the power value of the subcarrier is less than the fourth detection threshold value, clear the preset variable value zero.

It should be noted that, in step 1 above, if the noise detection device determines that the power value of the subcarrier is less than the first detection threshold, or in step 2 above, if the noise detection device determines that the power value of the subcarrier is less than the first detection threshold When the second detection threshold value is detected, the preset variable value is not cleared. For example, when the noise detection device determines that the power value of the subcarrier is greater than or equal to the first detection threshold value, it adds 1 to the preset variable value. When the power value of the subcarrier is less than the first detection threshold value, the preset variable value will not be incremented and cleared. However, if the noise detection device determines that the power value of the subcarrier is less than the third When detecting a threshold value, and/or determining that the power value of the subcarrier is less than the fourth detection threshold value, clearing the preset variable value to zero.

Step 4. When the noise detection device determines that the preset variable value is greater than 1 and the second average power value is greater than or equal to a preset power threshold value, determine that the subcarrier has noise.

For example, if the noise detection device determines that the power value of the subcarrier is greater than or equal to the first detection threshold value, it adds 1 to the preset variable value, and determines that the power value of the subcarrier is also greater than or equal to the first detection threshold value. When the second detection threshold value is detected, add 1 to the preset variable value. At this time, the preset variable value is 2. If the noise detection device determines that the power value of the subcarrier is greater than or equal to the third detection threshold value and greater than or equal to the fourth detection threshold value, then add 1 to the preset variable value, at this time, the preset variable value is 3, if the noise detection device further determines that the second average power value is greater than or equal to the preset power threshold value, the noise detection device determines that there is noise in the subcarrier.

Further, after determining that the subcarrier has noise, the noise detection device continues to determine whether the power value of the next subcarrier in the OFDM symbol to be detected satisfies the noise detection strategy, and continuously determines the power value of the subcarrier of the preset value When the noise detection policy is not satisfied, the noise detection result is determined.

Wherein, the next subcarrier includes the subcarrier corresponding to the identifier obtained by adding one to the identifier of the subcarrier, and the noise detection result includes the identifier corresponding to the subcarrier satisfying the noise detection strategy.

For example, the OFDM symbol to be detected includes 10 subcarriers, marked as 0, 1, 2...9, and divided into 2 sets according to the preset number of elements being 5, marked as 0 and 9 respectively. 1, wherein the set labeled 0 includes subcarriers labeled 0 to 4, and the set labeled 1 includes subcarriers labeled 5 to 9, if it is determined that the subcarrier labeled 0 in the set labeled 0 has noise , then continue to determine whether the subcarrier with the label 1 has noise, and determine whether the subcarrier with the label 2 to 9 has noise in turn, if it is determined that the subcarrier with the label 1 has noise, and the two (2 and 3) That is, the above-mentioned preset values, the two here are just examples) the continuous subcarriers do not satisfy the noise detection strategy (that is, there is no noise), then it is determined that the noise detection result includes the subcarriers labeled 0 and 0 in the subcarrier set There is noise in the subcarrier of 1, and the noise detection is continued from the subcarrier labeled 4. The specific detection method is the same as the detection method of the subcarriers labeled 0 to 3 above, so it will not be described in detail until the The subcarriers in the detected OFDM symbol are all detected, and noise processing is performed according to the noise detection results of the subcarriers in the OFDM symbol to be detected. In this way, multiple noise detection results may be determined in the OFDM symbol, so that the noise for more precise processing.

Specifically, the noise processing performed by the above-mentioned noise detection device may be that the noise detection device sends the noise detection result to the filter device and/or the carrier counter, and the filter device generates a corresponding filter coefficient according to the noise detection result, and according to the filter coefficient Filter the subcarriers with noise, the carrier setter will set the subcarrier with noise to 0, or set the amplitude of the subcarrier with noise as a constant (applicable to the phase of the subcarrier that the noise has a great influence on) case), or set the amplitude of the subcarrier with noise as a constant, and keep its phase (applicable to the case where the noise has little influence on the phase of the subcarrier).

By adopting the method in which the execution subject is the noise detection device, the noise detection device obtains the power value of the subcarrier in the OFDM symbol to be detected, determines the identity of the subcarrier set corresponding to the subcarrier, and according to the The identification of the subcarrier set obtains the corresponding noise detection threshold value. When the power value of the subcarrier is determined to meet the noise detection strategy according to the noise detection threshold value, it is determined that the subcarrier has noise. In this way, by the OFDM symbol to be detected Divide the sets and adopt a more accurate noise detection strategy for each set, so that even in the case of channel fading, accurate detection of signal noise can be achieved to ensure reliable signal transmission.

An embodiment of the present invention provides a noise detection method, as shown in FIG. 2 , including:

S201. The noise detection device determines sample OFDM symbols from received OFDM symbols.

Wherein, the sample OFDM symbol is a sample symbol determined for obtaining the power value of the subcarrier in the OFDM symbol to be detected.

S202. The noise detection device determines a power value of a subcarrier in the OFDM symbol to be detected according to the sample OFDM symbol.

Specifically, the noise detection device passes the formula according to the sample OFDM symbol:

$\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}$

Obtain the power value of the subcarrier in the OFDM symbol to be detected; wherein, P(n) is the power value of the subcarrier in the OFDM symbol to be detected, M is the number of the sample OFDM symbols, and m is the sample OFDM Symbol identifier, n is the identifier of the subcarrier, r _m,n is the nth subcarrier in the mth sample OFDM symbol.

It can be seen from the above formula that the calculation of the power value of the subcarriers in the OFDM symbol to be detected is to add the power values of the subcarriers corresponding to the same subcarrier identifier in each sample OFDM symbol, and obtain the sum obtained after the addition Value and the ratio of the number of sample OFDM symbols, so as to obtain the power value of the subcarrier corresponding to the subcarrier identifier in the OFDM symbol to be detected, for example, the noise detection device receives 4 OFDM symbols, and selects 2 sample OFDM symbol, then add the power values of the subcarriers marked as 0 in the two sample OFDM symbols, and add the value obtained after the addition to the number of sample OFDM symbols (that is, the two OFDM symbols selected above) By comparing, the power value of the subcarrier with the subcarrier identifier of 0 in the OFDM symbol to be detected is obtained, and the subcarrier identifier in the OFDM symbol to be detected is calculated sequentially according to the above method. The power values of the subcarriers, so as to obtain the power values of all the subcarriers in the to-be-detected OFDM symbol; this is just an example and not limited.

It should be noted that, for noise that exists for a long time, the more the number of sample OFDM symbols is determined, the more accurate the power value of the subcarriers in the OFDM symbol to be detected is, and the detection of subsequent noise is more accurate. However, Since the more sample OFDM symbols are selected, the delay of noise detection will be higher, and the complexity of calculation will be higher, which will cause the burden of system operation. Therefore, for the noise that exists for a long time, the determined sample OFDM symbols need to consider The burden of running the system. For bursty noise, it is necessary to detect the noise as soon as possible, so under the condition that the noise can be detected, the fewer determined sample OFDM symbols, the better.

In addition, the above identifier of the subcarrier may be a label of the subcarrier, for example, the subcarriers in the OFDM symbol may be labeled in the order of 0, 1, 2 . . . .

S203. The noise detection device determines the subcarrier set from the subcarriers in the OFDM symbol to be detected according to the preset number of elements.

Wherein, the subcarrier set is a set determined by the noise detection device according to a preset number of elements from the subcarriers in the OFDM symbol to be detected.

Specifically, the noise detection device determines the subcarrier set from the subcarriers in the OFDM symbol to be detected according to the preset number of elements, for example, if the preset number of elements is 5, then the subcarriers in the OFDM symbol to be detected Taking 5 as a set, if there are 10 subcarriers in the OFDM symbol, divide the 10 subcarriers into two sets.

Optionally, the identification of the subcarriers in each subcarrier set divided by the noise detection device may be continuous, for example, the OFDM symbol to be detected includes 10 subcarriers, and the labels are respectively marked as 0, 1, 2... ...9, and divided into 2 sets according to the preset number of elements being 5, and the labels are marked as 0 and 1 respectively, wherein, the set labeled 0 includes subcarriers labeled 0 to 4, and the set labeled 1 includes Subcarriers numbered 5 to 9. Of course, the identification of the subcarriers in each subcarrier set can also be discontinuous, such as taking the subcarriers marked as 0, 2, 4, 6 and 8 as a set, and the subcarriers marked as 1, 3, 5, 7 and 9 As a set, the present invention is not limited thereto.

In addition, if the determined number of preset elements cannot guarantee the average division of the subcarriers in the OFDM symbol, after determining the set of subcarriers, divide the remaining subcarriers into the determined set of subcarriers, for example, if the number of preset elements is 3, if there are 10 subcarriers in the OFDM symbol, divide the 10 subcarriers into 3 sets according to the preset number of elements, and at this time, if there is 1 subcarrier left, then divide the subcarriers into the above 3 sets in any of them.

S204. The noise detection device determines an identifier of a subcarrier set corresponding to the subcarrier.

Wherein, the determined subcarrier set includes an identifier of the subcarrier set, for example, it may be a label of the subcarrier set, such as labeling in the order of 0, 1, 2...,

S205. The noise detection device obtains the first average power value from the ratio of the sum of power values of all subcarriers in the subcarrier set corresponding to the identifier of the subcarrier set to the number of subcarriers in the subcarrier set.

Wherein, the first average power value is an average power value of subcarriers in the subcarrier set.

S206. The noise detection device determines a maximum power value from power values of subcarriers in the subcarrier set.

S207. The noise detection device obtains a first detection threshold, a second detection threshold, and a third detection threshold according to the first average power value, and obtains a fourth detection threshold according to the maximum power value.

Wherein, the first detection threshold value is: A·P _a (d-1), the second detection threshold value is: A·P _a (d+1), and the third detection threshold value is: A · P _a (d), the fourth detection threshold is

Wherein, d is the identity of the subcarrier set, P _a (d) is the first average power value, P _a (d+1) is the average power value of subcarriers in the d+1th subcarrier set, P _a (d -1) is the average power value of the subcarriers in the d-1th subcarrier set, P _m (d) is the maximum power value among the power values of the subcarriers in the subcarrier set, A is the first preset parameter, and B is the first preset parameter Two preset parameters.

S208. The noise detection equipment passes the formula:

The quantity of the subcarrier set is determined from the subcarriers in the OFDM symbol to be detected according to the preset number of elements.

Wherein, W is the number of the subcarrier set, N is the number of subcarriers in the OFDM symbol to be detected, and NS is the preset number of elements.

S209. The noise detection equipment passes the formula:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; W</span>}}\underset{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>$

Obtain the second average power value.

Wherein, the P _{t is} the second average power, P _a (d) is the first average power value, d is the identifier of the subcarrier set, W is the number of the subcarrier set, and the second average power value is The average power value obtained according to the average power value of subcarriers in all subcarrier sets in the OFDM symbol to be detected.

S210. The noise detection device determines that the power value of the subcarrier satisfies the noise threshold according to the first detection threshold, the second detection threshold, the third detection threshold, the fourth detection threshold and the second average power value. When detecting the strategy, it is determined that the subcarrier has noise.

Specifically, this step S210 specifically includes the following four steps:

Step 1. When the noise detection device determines that the power value of the subcarrier is greater than or equal to the first detection threshold value, it adds 1 to the preset variable value.

Wherein, the initial value of the preset variable value is 0.

Step 2: When the noise detection device determines that the power value of the subcarrier is greater than or equal to the second detection threshold value, add 1 to the preset variable value.

It should be noted that the implementation order of step 1 and step 2 is not limited, and step 2 may be performed first, and then step 1 may be performed.

Step 3: When the noise detection device determines that the power value of the subcarrier is greater than or equal to the third detection threshold and greater than or equal to the fourth detection threshold, add 1 to the preset variable value.

Further, when the noise detection device determines that the power value of the subcarrier is less than the third detection threshold value, and/or determines that the power value of the subcarrier is less than the fourth detection threshold value, clear the preset variable value zero.

It should be noted that, in step 1 above, if the noise detection device determines that the power value of the subcarrier is less than the first detection threshold, or in step 2 above, if the noise detection device determines that the power value of the subcarrier is less than the first detection threshold When the second detection threshold value is detected, the preset variable value is not cleared. For example, when the noise detection device determines that the power value of the subcarrier is greater than or equal to the first detection threshold value, it adds 1 to the preset variable value. When the power value of the subcarrier is less than the first detection threshold value, the preset variable value will not be incremented and cleared. However, if the noise detection device determines that the power value of the subcarrier is less than the third When detecting a threshold value, and/or determining that the power value of the subcarrier is less than the fourth detection threshold value, clearing the preset variable value to zero.

Step 4. When the noise detection device determines that the preset variable value is greater than 1 and the second average power value is greater than or equal to a preset power threshold value, determine that the subcarrier has noise.

For example, if the noise detection device determines that the power value of the subcarrier is greater than or equal to the first detection threshold value, it adds 1 to the preset variable value, and determines that the power value of the subcarrier is also greater than or equal to the first detection threshold value. When the second detection threshold value is detected, add 1 to the preset variable value. At this time, the preset variable value is 2. If the noise detection device determines that the power value of the subcarrier is greater than or equal to the third detection threshold value and greater than or equal to the fourth detection threshold value, then add 1 to the preset variable value, at this time, the preset variable value is 3, if the noise detection device further determines that the second average power value is greater than or equal to the preset power threshold value, the noise detection device determines that there is noise in the subcarrier.

S211. The noise detection device continues to determine whether the power value of the next subcarrier in the to-be-detected OFDM symbol satisfies the noise detection strategy, and determines the noise detection when the power value of the subcarrier with the preset value continuously determined does not satisfy the noise detection strategy result.

Wherein, the next subcarrier includes the subcarrier corresponding to the identifier obtained by adding one to the identifier of the subcarrier, and the noise detection result includes the identifier corresponding to the subcarrier satisfying the noise detection strategy.

For example, the OFDM symbol to be detected includes 10 subcarriers, marked as 0, 1, 2...9, and divided into 2 sets according to the preset number of elements being 5, marked as 0 and 9 respectively. 1, wherein the set labeled 0 includes subcarriers labeled 0 to 4, and the set labeled 1 includes subcarriers labeled 5 to 9, if it is determined that the subcarrier labeled 0 in the set labeled 0 has noise , then continue to determine whether the subcarrier with the label 1 has noise, and determine whether the subcarrier with the label 2 to 9 has noise in turn, if it is determined that the subcarrier with the label 1 has noise, and the two (2 and 3) That is, the above-mentioned preset values, the two here are just examples) the continuous subcarriers do not satisfy the noise detection strategy (that is, there is no noise), then it is determined that the noise detection result includes the subcarriers labeled 0 and 0 in the subcarrier set There is noise in the subcarrier of 1, and the noise detection is continued from the subcarrier labeled 4. The specific detection method is the same as the detection method of the subcarriers labeled 0 to 3 above, so it will not be described in detail until the The subcarriers in the detected OFDM symbol are all detected, and noise processing is performed according to the noise detection results of the subcarriers in the OFDM symbol to be detected. In this way, multiple noise detection results may be determined in the OFDM symbol, so that the noise for more precise processing.

Specifically, the noise processing performed by the above-mentioned noise detection device may be that the noise detection device sends the noise detection result to the filter device and/or the carrier counter, and the filter device generates a corresponding filter coefficient according to the noise detection result, and according to the filter coefficient Filter the subcarriers with noise, the carrier setter will set the subcarrier with noise to 0, or set the amplitude of the subcarrier with noise as a constant (applicable to the phase of the subcarrier that the noise has a great influence on) case), or set the amplitude of the subcarrier with noise as a constant, and keep its phase (applicable to the case where the noise has little influence on the phase of the subcarrier).

In this way, by dividing the OFDM symbols to be detected into sets and adopting a more accurate noise detection strategy for each set, even in the case of channel fading, accurate detection of signal noise can be achieved to ensure reliable signal transmission.

It should be noted that for the foregoing method embodiments, for the sake of simple description, they are expressed as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the described action sequence. Because of the present invention, certain steps may be performed in other orders or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification belong to preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

An embodiment of the present invention provides a noise detection device 30, as shown in FIG. 3 , including:

The obtaining unit 31 is configured to obtain the power value of the subcarrier in the OFDM symbol to be detected.

Optionally, the obtaining unit 31 is specifically configured to determine a sample OFDM symbol from received OFDM symbols, where the sample OFDM symbol is a sample symbol determined for obtaining a power value of a subcarrier in the to-be-detected OFDM symbol.

According to the sample OFDM symbol passing formula:

$\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}$

Obtain the power value of the subcarrier in the OFDM symbol to be detected; wherein, P(n) is the power value of the subcarrier in the OFDM symbol to be detected, M is the number of the sample OFDM symbols, and m is the sample OFDM Symbol identifier, n is the identifier of the subcarrier, r _m,n is the nth subcarrier in the mth sample OFDM symbol.

It can be seen from the above formula that the calculation of the power value of the subcarriers in the OFDM symbol to be detected is to add the power values of the subcarriers corresponding to the same subcarrier identifier in each sample OFDM symbol, and obtain the sum obtained after the addition Value and the ratio of the number of sample OFDM symbols, so as to obtain the power value of the subcarrier corresponding to the subcarrier identifier in the OFDM symbol to be detected, for example, the noise detection device receives 4 OFDM symbols, and selects 2 sample OFDM symbol, then add the power values of the subcarriers marked as 0 in the 2 sample OFDM symbols, and add the value obtained after the addition to the number of sample OFDM symbols (that is, the 2 OFDM symbols selected above) By comparing, the power value of the subcarrier with the subcarrier identifier of 0 in the OFDM symbol to be detected is obtained, and the subcarrier identifier in the OFDM symbol to be detected is 1 to the maximum value corresponding to the subcarrier identifier. The power values of the subcarriers, so as to obtain the power values of all the subcarriers in the to-be-detected OFDM symbol; this is just an example and not limited.

It should be noted that, for noise that exists for a long time, the more the number of sample OFDM symbols is determined, the more accurate the power value of the subcarriers in the OFDM symbol to be detected is, and the detection of subsequent noise is more accurate. However, Since the more sample OFDM symbols are selected, the delay of noise detection will be higher, and the complexity of calculation will be higher, which will cause the burden of system operation. Therefore, for the noise that exists for a long time, the determined sample OFDM symbols need to consider The burden of running the system. For bursty noise, it is necessary to detect the noise as soon as possible, so under the condition that the noise can be detected, the fewer determined sample OFDM symbols, the better.

In addition, the above identifier of the subcarrier may be a label of the subcarrier, for example, the subcarriers in the OFDM symbol may be labeled in the order of 0, 1, 2 . . . .

The processing unit 32 is configured to determine the identity of the subcarrier set corresponding to the subcarrier, and obtain the corresponding noise detection threshold value according to the identity of the subcarrier set, and determine that the acquisition unit 31 obtains according to the noise detection threshold value When the power value of the subcarrier satisfies the noise detection strategy, it is determined that the subcarrier has noise.

Wherein, the subcarrier set is a set determined by the noise detection device according to a preset number of elements from the subcarriers in the OFDM symbol to be detected.

Specifically, the processing unit 32 is further configured to, before determining the identity of the subcarrier set corresponding to the subcarrier, determine the subcarrier set from the subcarriers in the OFDM symbol to be detected according to the preset number of elements.

For example, if the preset number of elements is 5, the subcarriers in the OFDM symbol to be detected are 5 as a set, and if there are 10 subcarriers in the OFDM symbol, then the 10 subcarriers are divided into two sets .

Optionally, the identification of the subcarriers in each subcarrier set divided by the noise detection device may be continuous, for example, the OFDM symbol to be detected includes 10 subcarriers, and the labels are respectively marked as 0, 1, 2... ...9, and divided into 2 sets according to the preset number of elements being 5, and the labels are marked as 0 and 1 respectively, wherein, the set labeled 0 includes subcarriers labeled 0 to 4, and the set labeled 1 includes Subcarriers numbered 5 to 9. Of course, the identification of the subcarriers in each subcarrier set can also be discontinuous, such as taking the subcarriers marked as 0, 2, 4, 6 and 8 as a set, and the subcarriers marked as 1, 3, 5, 7 and 9 As a set, the present invention is not limited thereto.

In addition, if the determined number of preset elements cannot guarantee the average division of the subcarriers in the OFDM symbol, after determining the set of subcarriers, divide the remaining subcarriers into the determined set of subcarriers, for example, if the number of preset elements is 3, if there are 10 subcarriers in the OFDM symbol, divide the 10 subcarriers into 3 sets according to the preset number of elements, and at this time, if there is 1 subcarrier left, then divide the subcarriers into the above 3 sets in any of them.

It should be noted that the determined subcarrier set includes an identifier of the subcarrier set, for example, may be a label of the subcarrier set, such as labeling in the order of 0, 1, 2 . . . .

Further, the processing unit 32 is specifically configured to obtain the first average power by the ratio of the sum of the power values of all subcarriers in the subcarrier set corresponding to the identifier of the subcarrier set to the number of subcarriers in the subcarrier set. value, determine the maximum power value from the power values of the subcarriers in the subcarrier set, and obtain the detection threshold value according to the first average power value and the maximum power value.

Wherein, the first average power value is an average power value of subcarriers in the subcarrier set.

Further, the processing unit is specifically configured to obtain a first detection threshold value according to the first average power value: wherein, the first detection threshold value is: A·P _a (d-1)

Obtain the second detection threshold value according to the first average power value: Wherein, the second detection threshold value is: A·P _a (d+1)

Obtain the third detection threshold value according to the first average power value: Wherein, the third detection threshold value is: A·P _a (d)

Obtain the fourth detection threshold value according to the maximum power value: Wherein, the fourth detection threshold value is:

Wherein, d is the identity of the subcarrier set, P _a (d) is the first average power value, P _a (d+1) is the average power value of subcarriers in the d+1th subcarrier set, P _a (d -1) is the average power value of the subcarriers in the d-1th subcarrier set, P _m (d) is the maximum power value among the power values of the subcarriers in the subcarrier set, A is the first preset parameter, and B is the first preset parameter Two preset parameters.

Furthermore, the processing unit 32 is also configured to, before determining that the subcarrier has noise, use the formula:

Determine the number of subcarrier sets from the subcarriers in the OFDM symbol to be detected according to the preset number of elements, where W is the number of the subcarrier set, and N is the number of subcarriers in the OFDM symbol to be detected , NS is the preset number of elements; and through the formula:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; W</span>}}\underset{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>$

Obtain the second average power value; wherein, the P _{t is} the second average power, P _a (d) is the first average power value, d is the identity of the subcarrier set, W is the number of the subcarrier set, The second average power value is an average power value obtained from average power values of subcarriers in all subcarrier sets in the OFDM symbol to be detected.

The processing unit 32 is specifically configured to, when it is determined that the power value of the subcarrier is greater than or equal to the first detection threshold value, add 1 to the preset variable value, where the initial value of the preset variable value is 0;

When it is determined that the power value of the subcarrier is greater than or equal to the second detection threshold value, add 1 to the preset variable value;

When it is determined that the power value of the subcarrier is greater than or equal to the third detection threshold and greater than or equal to the fourth detection threshold, add 1 to the preset variable value;

When it is determined that the preset variable value is greater than 1 and the second average power value is greater than or equal to a preset power threshold value, it is determined that the subcarrier has noise.

Optionally, the processing unit 32 is further configured to, when it is determined that the power value of the subcarrier is less than the third detection threshold, and/or when it is determined that the power value of the subcarrier is less than the fourth detection threshold, set The preset variable value is cleared to zero.

For example, if the noise detection device determines that the power value of the subcarrier is greater than or equal to the first detection threshold value, it adds 1 to the preset variable value, and determines that the power value of the subcarrier is also greater than or equal to the first detection threshold value. When the second detection threshold value is detected, add 1 to the preset variable value. At this time, the preset variable value is 2. If the noise detection device determines that the power value of the subcarrier is greater than or equal to the third detection threshold value and greater than or equal to the fourth detection threshold value, then add 1 to the preset variable value, at this time, the preset variable value is 3, if the noise detection device further determines that the second average power value is greater than or equal to the preset power threshold value, the noise detection device determines that there is noise in the subcarrier.

Optionally, the processing unit 32 is also configured to, after determining that the subcarrier has noise, continue to determine whether the power value of the next subcarrier in the OFDM symbol to be detected satisfies the noise detection strategy, and continuously determine the preset value When the power value of the subcarrier does not satisfy the noise detection strategy, determine the noise detection result.

Wherein, the noise detection result includes an identifier corresponding to a subcarrier satisfying the noise detection strategy, and the next subcarrier includes a subcarrier corresponding to an identifier obtained by adding one to the identifier of the subcarrier.

For example, the OFDM symbol to be detected includes 10 subcarriers, marked as 0, 1, 2...9, and divided into 2 sets according to the preset number of elements being 5, marked as 0 and 9 respectively. 1, wherein the set labeled 0 includes subcarriers labeled 0 to 4, and the set labeled 1 includes subcarriers labeled 5 to 9, if it is determined that the subcarrier labeled 0 in the set labeled 0 has noise , then continue to determine whether the subcarrier with the label 1 has noise, and determine whether the subcarrier with the label 2 to 9 has noise in turn, if it is determined that the subcarrier with the label 1 has noise, and the two (2 and 3) That is, the above-mentioned preset values, the two here are just examples) the continuous subcarriers do not satisfy the noise detection strategy (that is, there is no noise), then it is determined that the noise detection result includes the subcarriers labeled 0 and 0 in the subcarrier set There is noise in the subcarrier of 1, and the noise detection is continued from the subcarrier labeled 4. The specific detection method is the same as the detection method of the subcarriers labeled 0 to 3 above, so it will not be described in detail until the The subcarriers in the detected OFDM symbol are all detected, and noise processing is performed according to the noise detection results of the subcarriers in the OFDM symbol to be detected. In this way, multiple noise detection results may be determined in the OFDM symbol, so that the noise is processed more precise handling.

Specifically, the noise processing performed by the above-mentioned noise detection device may be that the noise detection device sends the noise detection result to the filter device and/or the carrier counter, and the filter device generates a corresponding filter coefficient according to the noise detection result, and according to the filter coefficient Filter the subcarriers with noise, the carrier setter will set the subcarrier with noise to 0, or set the amplitude of the subcarrier with noise as a constant (applicable to the phase of the subcarrier that the noise has a great influence on) case), or set the amplitude of the subcarrier with noise as a constant, and keep its phase (applicable to the case where the noise has little influence on the phase of the subcarrier).

Using the above-mentioned noise detection device, the noise detection device obtains the power value of the subcarrier in the orthogonal frequency division multiplexing OFDM symbol to be detected, determines the identity of the subcarrier set corresponding to the subcarrier, and obtains according to the identity of the subcarrier set Corresponding noise detection threshold value, when the power value of the subcarrier is determined to meet the noise detection strategy according to the noise detection threshold value, it is determined that the subcarrier has noise. In this way, by dividing the OFDM symbols to be detected into sets, and for each The set adopts a more accurate noise detection strategy, so that even in the scenario of channel fading, it can realize accurate detection of signal noise to ensure reliable signal transmission.

Those skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process and description of the noise detection device described above can refer to the corresponding process in the foregoing method embodiments, which will not be repeated here.

An embodiment of the present invention provides a noise detection device 40. As shown in FIG. 4, the noise detection device 40 includes:

Processor (processor) 41, communication interface (Communications Interface) 42, memory (memory) 43 and communication bus 44; Wherein, described processor 41, described communication interface 42 and described memory 43 complete by described communication bus 44 mutual communication.

The processor 41 may be a central processing unit CPU, or an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention.

The memory 43 is used to store program codes, and the program codes include computer operation instructions. The memory 43 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one magnetic disk memory.

The communication interface 42 is used to realize connection and communication between these devices.

The processor 41 executes a program code for obtaining the power value of the subcarrier in the OFDM symbol to be detected, determining the identity of the subcarrier set corresponding to the subcarrier, and obtaining the corresponding noise detection according to the identity of the subcarrier set Threshold value, and when it is determined according to the noise detection threshold value that the power value of the subcarrier satisfies the noise detection strategy, it is determined that the subcarrier has noise, wherein the subcarrier set is the noise detection device from the OFDM to be detected A set determined according to a preset number of elements in subcarriers within a symbol.

Optionally, the processor 41 is further configured to, before determining the identifier of the subcarrier set corresponding to the subcarrier, determine the subcarrier set from the subcarriers in the OFDM symbol to be detected according to a preset number of elements.

Optionally, the processor 41 is specifically configured to determine sample OFDM symbols from received OFDM symbols. Wherein, the sample OFDM symbol is a sample symbol determined for obtaining the power value of the subcarrier in the OFDM symbol to be detected.

According to the sample OFDM symbol passing formula:

$\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}$

Obtain the power value of the subcarrier in the OFDM symbol to be detected; wherein, P(n) is the power value of the subcarrier in the OFDM symbol to be detected, M is the number of the sample OFDM symbols, and m is the sample OFDM Symbol identifier, n is the identifier of the subcarrier, r _m,n is the nth subcarrier in the mth sample OFDM symbol.

Optionally, the processor 41 is specifically configured to obtain the first average A power value, determining a maximum power value from power values of subcarriers in the subcarrier set; obtaining a detection threshold value according to the first average power value and the maximum power value.

Wherein, the first average power value is an average power value of subcarriers in the subcarrier set.

Optionally. The processor 41 is specifically configured to obtain a first detection threshold value according to the first average power value: wherein, the first detection threshold value is: A·P _a (d-1)

Obtain the second detection threshold value according to the first average power value: Wherein, the second detection threshold value is: A·P _a (d+1)

Obtain the third detection threshold value according to the first average power value: Wherein, the third detection threshold value is: A·P _a (d)

Obtain the fourth detection threshold value according to the maximum power value: Wherein, the fourth detection threshold value is:

Wherein, d is the identity of the subcarrier set, P _a (d) is the first average power value, P _a (d+1) is the average power value of subcarriers in the d+1th subcarrier set, P _a (d -1) is the average power value of the subcarriers in the d-1th subcarrier set, P _m (d) is the maximum power value among the power values of the subcarriers in the subcarrier set, A is the first preset parameter, and B is the first preset parameter Two preset parameters.

Optionally, the processor is specifically configured to, before determining that the subcarrier has noise, use the formula:

Determine the number of subcarrier sets from the subcarriers in the OFDM symbol to be detected according to the preset number of elements, where W is the number of the subcarrier set, and N is the number of subcarriers in the OFDM symbol to be detected , NS is the preset number of elements; and through the formula:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; W</span>}}\underset{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>$

Obtain the second average power value; wherein, the P _{t is} the second average power, P _a (d) is the first average power value, d is the identity of the subcarrier set, W is the number of the subcarrier set, The second average power value is an average power value obtained from the average power value of subcarriers in all subcarrier sets in the OFDM symbol to be detected;

When it is determined that the power value of the subcarrier is greater than or equal to the first detection threshold value, adding 1 to the preset variable value, where the initial value of the preset variable value is 0;

When it is determined that the power value of the subcarrier is greater than or equal to the second detection threshold value, add 1 to the preset variable value;

When it is determined that the power value of the subcarrier is greater than or equal to the third detection threshold and greater than or equal to the fourth detection threshold, add 1 to the preset variable value;

When it is determined that the preset variable value is greater than 1 and the second average power value is greater than or equal to a preset power threshold value, it is determined that the subcarrier has noise.

Optionally, the processor 41 is further configured to, when it is determined that the power value of the subcarrier is less than the third detection threshold, and/or when it is determined that the power value of the subcarrier is less than the fourth detection threshold, set The preset variable value is cleared to zero.

Optionally, the processor 41 is also configured to, after determining that the subcarrier has noise, continue to determine whether the power value of the next subcarrier in the OFDM symbol to be detected satisfies the noise detection strategy, and continuously determine the preset value When the power value of the subcarrier does not satisfy the noise detection strategy, determine the noise detection result.

Wherein, the next subcarrier includes the subcarrier corresponding to the identifier obtained by adding one to the identifier of the subcarrier, and the noise detection result includes the identifier corresponding to the subcarrier satisfying the noise detection strategy.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (14)

1. A method for noise detection, characterized in that, comprising: The noise detection device obtains the power value of the subcarrier in the orthogonal frequency division multiplexing OFDM symbol to be detected; Determining the identity of the subcarrier set corresponding to the subcarrier set, obtained by the ratio of the sum of the power values of all subcarriers in the subcarrier set corresponding to the identity of the subcarrier set to the number of subcarriers in the subcarrier set A first average power value; wherein, the first average power value is an average power value of subcarriers in the subcarrier set; determining a maximum power value from power values of subcarriers within the set of subcarriers; A noise detection threshold value is obtained according to the first average power value and the maximum power value; wherein, the subcarrier set is the subcarriers in the OFDM symbol to be detected by the noise detection device according to preset A collection with a determined number of elements; When it is determined according to the noise detection threshold that the power value of the subcarrier satisfies a noise detection strategy, it is determined that the subcarrier has noise. 2. The method according to claim 1, wherein before the identification of the set of subcarriers corresponding to the subcarriers is determined, the method further comprises: The set of subcarriers is determined from the subcarriers in the OFDM symbol to be detected according to a preset number of elements. 3. The method according to claim 1 or 2, wherein the noise detection device obtaining the power value of the subcarrier in the OFDM symbol to be detected comprises: Determining a sample OFDM symbol from the received OFDM symbol, wherein the sample OFDM symbol is a sample symbol determined for obtaining a power value of a subcarrier in the OFDM symbol to be detected; According to the sample OFDM symbol passing formula: $\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}$ Obtain the power value of the subcarrier in the OFDM symbol to be detected; Wherein, P(n) is the power value of the subcarrier in the OFDM symbol to be detected, M is the quantity of the sample OFDM symbol, and m is The identifier of the sample OFDM symbol, n is the identifier of the subcarrier, r _m,n is the nth subcarrier in the mth sample OFDM symbol. 4. The method according to claim 3, wherein said obtaining a noise detection threshold value according to said first average power value and said maximum power value comprises: A first detection threshold value is obtained according to the first average power value: wherein, the first detection threshold value is: A· _Pa (d-1) A second detection threshold value is obtained according to the first average power value: wherein, the second detection threshold value is: A·P _a (d+1) A third detection threshold value is obtained according to the first average power value: wherein, the third detection threshold value is: A·P _a (d) A fourth detection threshold value is obtained according to the maximum power value: wherein, the fourth detection threshold value is: Wherein, d is the identifier of the subcarrier set, P _a (d) is the first average power value, P _a (d+1) is the average power value of the subcarriers in the d+1th subcarrier set, and P _a (d-1) is the average power value of the subcarriers in the d-1th subcarrier set, P _m (d) is the maximum power value among the power values of the subcarriers in the subcarrier set, A is the first preset parameter, B is the second preset parameter. 5. The method according to claim 4, wherein, before determining that there is noise in the subcarrier, the method further comprises: By formula: Determine the number of subcarrier sets from the subcarriers in the OFDM symbols to be detected according to the preset number of elements, where W is the number of the subcarrier sets, and N is the number of subcarriers in the OFDM symbols to be detected. The number of subcarriers, N _S is the preset number of elements; By formula: ${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; W</span>}}\underset{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>$ Obtain a second average power value; wherein, the P _t is the second average power, P _a (d) is the first average power value, d is the identity of the subcarrier set, and W is the subcarrier set The number of carrier sets, the second average power value is an average power value obtained from the average power value of subcarriers in all subcarrier sets in the OFDM symbol to be detected; When determining that the power value of the subcarrier satisfies the noise detection strategy according to the noise detection threshold value, determining that there is noise in the subcarrier includes: When it is determined that the power value of the subcarrier is greater than or equal to the first detection threshold value, adding 1 to the preset variable value, where the initial value of the preset variable value is 0; When it is determined that the power value of the subcarrier is greater than or equal to the second detection threshold value, adding 1 to the preset variable value; When it is determined that the power value of the subcarrier is greater than or equal to the third detection threshold and greater than or equal to the fourth detection threshold, add 1 to the preset variable value; When it is determined that the preset variable value is greater than 1 and the second average power value is greater than or equal to a preset power threshold value, it is determined that the subcarrier has noise. 6. The method according to claim 5, wherein after determining that the power value of the subcarrier is less than the third detection threshold value, and/or determining that the power value of the subcarrier is less than the fourth When the threshold value is detected, the preset variable value is cleared. 7. The method according to claim 5 or 6, wherein after determining that there is noise in the subcarrier, the method further comprises: Continue to determine whether the power value of the next subcarrier in the OFDM symbol to be detected meets the noise detection strategy; wherein the next subcarrier includes the subcarrier corresponding to the identifier obtained by adding one to the identifier of the subcarrier; When the power values of the subcarriers whose preset values are continuously determined do not satisfy the noise detection strategy, determine a noise detection result, wherein the noise detection result includes an identifier corresponding to a subcarrier that satisfies the noise detection strategy. 8. A noise detection device, characterized in that, comprising: An acquisition unit, configured to acquire the power value of the subcarrier in the orthogonal frequency division multiplexing OFDM symbol to be detected; The processing unit is configured to determine the identity of the subcarrier set corresponding to the subcarrier set, and the sum of the power values of all subcarriers in the subcarrier set corresponding to the subcarrier set identity and the subcarriers in the subcarrier set The first average power value is obtained from the ratio of the number of subcarriers, the maximum power value is determined from the power values of the subcarriers in the subcarrier set, and the detection threshold value is obtained according to the first average power value and the maximum power value, where , the first average power value is the average power value of the subcarriers in the subcarrier set; and when it is determined according to the noise detection threshold value that the power value of the subcarriers acquired by the acquisition unit satisfies the noise detection strategy, determine Noise exists in the subcarrier; wherein, the subcarrier set is a set determined by the noise detection device according to a preset number of elements from the subcarriers in the OFDM symbol to be detected. 9. The device according to claim 8, wherein the processing unit is further configured to, before determining the identity of the subcarrier set corresponding to the subcarrier, from the OFDM symbol to be detected The set of subcarriers is determined according to the preset number of elements in the subcarriers. 10. The device according to claim 8 or 9, wherein the obtaining unit is specifically configured to determine sample OFDM symbols from received OFDM symbols, wherein the sample OFDM symbols are used to obtain the to-be The sample symbol determined by the power value of the subcarrier in the detected OFDM symbol; According to the sample OFDM symbol passing formula: $\mathrm{<span\; class="notranslate">\; P</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; m</span>}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{<span\; class="notranslate">\; |</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; no</span>}}<span\; class="notranslate">\; |</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}$ Obtain the power value of the subcarrier in the OFDM symbol to be detected; Wherein, P(n) is the power value of the subcarrier in the OFDM symbol to be detected, M is the quantity of the sample OFDM symbol, and m is The identifier of the sample OFDM symbol, n is the identifier of the subcarrier, r _m,n is the nth subcarrier in the mth sample OFDM symbol. 11. The device according to claim 10, wherein the processing unit is specifically configured to obtain a first detection threshold value according to the first average power value: wherein, the first detection threshold value is : A·P _a (d-1) A second detection threshold value is obtained according to the first average power value: wherein, the second detection threshold value is: A·P _a (d+1) A third detection threshold value is obtained according to the first average power value: wherein, the third detection threshold value is: A·P _a (d) A fourth detection threshold value is obtained according to the maximum power value: wherein, the fourth detection threshold value is: Wherein, d is the identifier of the subcarrier set, P _a (d) is the first average power value, P _a (d+1) is the average power value of the subcarriers in the d+1th subcarrier set, and P _a (d-1) is the average power value of the subcarriers in the d-1th subcarrier set, P _m (d) is the maximum power value among the power values of the subcarriers in the subcarrier set, A is the first preset parameter, B is the second preset parameter. 12. The device according to claim 11, wherein the processing unit is further configured to, before determining that there is noise in the subcarrier, use the formula: Determine the number of subcarrier sets from the subcarriers in the OFDM symbols to be detected according to the preset number of elements, where W is the number of the subcarrier sets, and N is the number of subcarriers in the OFDM symbols to be detected. The number of subcarriers, N _S is the preset number of elements; By formula: ${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; W</span>}}\underset{\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; W</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}{\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>$ Obtain a second average power value; wherein, the P _t is the second average power, P _a (d) is the first average power value, d is the identity of the subcarrier set, and W is the subcarrier set The number of carrier sets, the second average power value is an average power value obtained from the average power value of subcarriers in all subcarrier sets in the OFDM symbol to be detected; The processing unit is specifically configured to, when it is determined that the power value of the subcarrier is greater than or equal to the first detection threshold value, add 1 to the preset variable value, wherein the initial value of the preset variable value is is 0; When it is determined that the power value of the subcarrier is greater than or equal to the second detection threshold value, adding 1 to the preset variable value; When it is determined that the power value of the subcarrier is greater than or equal to the third detection threshold and greater than or equal to the fourth detection threshold, add 1 to the preset variable value; When it is determined that the preset variable value is greater than 1 and the second average power value is greater than or equal to a preset power threshold value, it is determined that the subcarrier has noise. 13. The device according to claim 12, wherein the processing unit is further configured to determine that the power value of the subcarrier is less than the third detection threshold, and/or determine that the subcarrier When the power value of is smaller than the fourth detection threshold value, the preset variable value is cleared to zero. 14. The device according to claim 12 or 13, wherein the processing unit is further configured to continue to determine the next subcarrier in the OFDM symbol to be detected after determining that there is noise in the subcarrier Whether the power value satisfies the noise detection strategy, and when the power value of the subcarriers with preset values continuously determined does not satisfy the noise detection strategy, determine the noise detection result, wherein the noise detection result includes the subcarriers corresponding to the noise detection strategy An identifier, the next subcarrier includes a subcarrier corresponding to the identifier obtained by adding one to the identifier of the subcarrier.