WO2021159876A1 - Communication method and system, data sending device, and data receiving device - Google Patents

Abstract

A communication method and system, a data sending device, and a data receiving device. The communication method comprises: a data sending device sends a handshake signal comprising a first preamble to a data receiving device; the data sending device receives a handshake response signal sent by the data receiving device; the data sending device sends a data signal comprising a second preamble to the data receiving device, the length of the second preamble being less than that of the first preamble.

Description

Communication method and system, data sending equipment, data receiving equipment

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on February 14, 2020, the application number is 202010095188.8, and the invention title is "a communication method and system, data sending equipment, and data receiving equipment". The content should be It is understood to be incorporated into the present disclosure by reference.

Technical field

The embodiments of the present application relate to, but are not limited to, the field of communication technology, and in particular to a communication method and system, a data sending device, and a data receiving device.

Background technique

Long Range (LoRa) wireless transmission is a wireless transmission technology based on spread spectrum technology. It is characterized by long distance, low power consumption, multiple nodes, low cost, and strong anti-interference characteristics. It can be widely used in smart cities, In scenarios such as traffic monitoring, logistics, and agriculture.

LoRa communication technology generally uses Channel Activity Detection (CAD) to reduce the power consumption of the system. However, if a large amount of data needs to be sent and received during the communication process, the use of channel activity detection will greatly increase the data transmission time. This will increase the power consumption of the system.

Summary of the invention

The following is an overview of the topics detailed in this article. This summary is not intended to limit the scope of protection of the claims.

An embodiment of the application provides a communication method, including: a data sending device sends a handshake signal including a first preamble to a data receiving device; the data sending device receives a handshake response signal sent by the data receiving device; the data The sending device sends a data signal including a second preamble to the data receiving device, and the length of the second preamble is smaller than the length of the first preamble.

In an exemplary embodiment, the handshake signal further includes device information of the data sending device and length information of the second preamble.

In an exemplary embodiment, the second preamble is the lowest N bytes or the highest N bytes of the first preamble, N is a natural number greater than 1 and less than M, and M is the first preamble. The total number of bytes of a preamble.

In an exemplary embodiment, the data sending device receives a data reception success signal sent by the data receiving device.

An embodiment of the present application also provides a communication method, including: a data receiving device performs a second-duration channel activity detection every time after a first-duration sleep; responding to the result of the channel activity detection being undetected To the handshake signal including the first preamble sent by the data sending device, the data receiving device continues to sleep for the first duration; in response to the result of the channel activity detection, it is detected that the first preamble sent by the data sending device is included The data receiving device sends a handshake response signal to the data sending device and receives a data signal including a second preamble sent by the data sending device, where the handshake signal includes the first preamble and the data The device information of the sending device and the length information of the second preamble, where the length of the second preamble is smaller than the length of the first preamble.

In an exemplary embodiment, after the data receiving device receives the data signal including the second preamble, the method further includes: the data receiving device sends a data reception success signal to the data sending device .

An embodiment of the present application also provides a communication method, including: a data sending device sends a handshake signal including a first preamble to a data receiving device; and the data receiving device performs a second duration after each sleep for the first duration Channel activity detection; in response to the result of the channel activity detection detecting a handshake signal including the first preamble sent by the data sending device, the data receiving device sends a handshake response signal to the data sending device, the handshake The signal includes a first preamble, device information of the data sending device, and length information of a second preamble. The length of the second preamble is less than the length of the first preamble; the data sending device receives the data. The handshake response signal sent by the device, and sends the data signal including the second preamble to the data receiving device; the data receiving device receives the data signal including the second preamble sent by the data sending device and continues to perform the first time period Hibernate.

An embodiment of the present application also provides a data sending device, including: a first handshake module and a first transmission module, wherein the first handshake module is configured to send a handshake signal including the first preamble to the data receiving device and receive The handshake response signal sent by the data receiving device; the first transmission module is configured to send a data signal including a second preamble to the data receiving device, and the length of the second preamble is smaller than the length of the first preamble.

The embodiments of the present application also provide a data receiving device, which is generally a mobile terminal that requires low power consumption, and includes a sleep control module, a channel activity detection module, and a second transmission module. The sleep control module is set to pass through After the first period of sleep, wake up the data receiving device and send a channel activity detection notification to the channel activity detection module; after receiving the sleep notification, perform a first period of sleep; the channel activity detection module is set to receive the channel activity After the detection notification, a second-duration channel activity detection is performed, and in response to not detecting the handshake signal including the first preamble sent by the data sending device, the dormancy notification is sent to the dormancy control module; in response to the detection of the data sending device sending If the handshake signal includes the first preamble, the data reception notification is sent to the second transmission module; the second transmission module is configured to send a handshake response signal to the data transmission device after receiving the data reception notification and receive the The data signal including the second preamble sent by the data sending device, and the dormancy notification is sent to the dormancy control module after the reception is completed, the handshake signal includes the first preamble, the device information of the data sending device, and the length of the second preamble Information, the length of the second preamble is less than the length of the first preamble.

An embodiment of the present application also provides a communication system, including the data sending device and the data receiving device as described above.

After reading and understanding the summary of the drawings and the embodiments of the present application, other aspects can be understood.

Description of the drawings

FIG. 1 is a schematic diagram of device power consumption at each stage of data transmission in a channel activity detection mode according to an embodiment of the application;

FIG. 2 is a schematic diagram of a communication flow between a data sending device and a data receiving device according to an embodiment of the application;

FIG. 3 is a schematic flowchart of a communication method according to an embodiment of the application;

4 is a schematic diagram of a long-distance wireless transmission data packet structure according to an embodiment of the application;

FIG. 5 is a schematic diagram of a communication principle between a data sending device and a data receiving device according to an embodiment of the application;

FIG. 6 is a schematic flowchart of another communication method according to an embodiment of the application;

FIG. 7 is a schematic flowchart of another communication method according to an embodiment of the application;

FIG. 8 is a schematic structural diagram of a data sending device according to an embodiment of the application;

FIG. 9 is a schematic structural diagram of a data receiving device according to an embodiment of the application.

Detailed ways

Hereinafter, the embodiments of the present application will be described with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary, and are not intended to limit the scope of the application.

In the LoRa communication process, in order to ensure that communication data is received in a timely and effective manner, except when sending data, the LoRa device (here LoRa device refers to the data receiving device, generally a low-power mobile terminal, the data receiving in this embodiment device may receive data, can send data, but most of the time in a receiving state) generally is in a receiving state, but in a power reception state LoRa apparatus is very large, the power consumption LoRa device reception state is denoted P _rec ( In actual test, the power consumption is generally 20mA×T, mA is the current unit of mA, and T is the time). In one embodiment, the method of channel activity detection is adopted to reduce the power consumption of the LoRa device. As shown in Figure 1, the first duration T _sleep is the sleep duration of the LoRa device, the second duration T _wk is the duration of the LoRa device's channel activity detection, and the period T _cad during which the LoRa device performs channel activity detection is the first duration T _sleep The sum of the second duration T _{wk , T cad} = T _sleep + T _wk , the power consumption of the LoRa device in the sleep state is the first power consumption P _sleep (usually on the order of uA×T, uA is the current unit microampere ), the power consumption of the device during the preamble detection period is the second power consumption P _wk (the power consumption in actual detection is generally as high as 120mA×T), and the _{power consumption of the device during the data reception period T rec} is the third power consumption P _rec , P _{sleep is} much smaller than P _rec . The LoRa device will wake up periodically to detect whether the preamble is received. The wake-up time is the same as the channel activity detection time T _wk . In this way, during the entire channel activity detection cycle, if there is no data to receive (that is, the preamble is not detected), Only in the second time period T _wk , the LoRa device is in the awake state, in the rest of the period (T _cad -T _wk ), the LoRa device will be in the dormant state; if the preamble is detected, indicating that there is data to be received, the LoRa device is turned on Receive function, receive data (as shown in the _{T rec period).} The second time length T _{wk is} generally several milliseconds (such as 1 to 2 milliseconds), and T _cad can be set according to the length of the preamble. For example, when the current preamble transmission time is 600 milliseconds, T _cad can be 500 millisecond.

When channel activity detection is enabled and no data is received, the device power consumption P ₀ is

Remember T _cad /T _wk =n (the magnitude of n is generally a hundred), then the formula (1) can be approximated as

Thus: P ₀ <P _rec , the channel activity detection can effectively reduce the power consumption of the device. However, in order to ensure that the data can be received, it is generally required that the data sending device (generally a gateway server with no special requirements for power consumption, the data sending device in this embodiment can send data or receive data) to send the first preamble. The duration must be greater than or equal to T _cad , and the reception duration T _{rec of the} data receiving device includes the preamble reception duration T _pre , the reception duration of valid data (T _data ), and the delay duration after reception T _delay (T _delay can be set by yourself The minimum value is 0. The present disclosure does not consider the influence of delay after reception. The following considers that T _delay is 0), namely

T _rec ＝T _pre +T _data (3)

When channel activity detection is enabled and data is received, the device power consumption P ₁ is

Assuming that the length of the preamble is m times the effective data length, then T _pre =m×T _data , combining formula (3) and formula (4), we can get

When multiple frames of data need to be continuously transmitted, only the first frame needs to be tested for preamble, and subsequent frames are not required. Assuming that M frames of data need to be transmitted, then the power consumption _PM for M frame data transmission is

When M is large enough, formula (6) can be approximated as

P _M ＝P _rec (7)

The required time T _M is

T _M ＝M×(m+1)×T _data (8)

It can be seen from formula (8) that too long a preamble transmission time (m is very large) will reduce the transmission efficiency of valid data, especially for data that requires multiple frames to complete the transmission, the transmission time will be multiples Increase, which is very detrimental to the user experience.

Therefore, as shown in FIG. 2, the present disclosure divides the data transmission into two phases: a handshake phase and a data transmission phase.

In this embodiment, a long preamble is used in the handshake phase to ensure that the data sent by the data sending device can be received by the data receiving device. For example, the data sending device first sends a handshake signal containing the first preamble and the device information of the data sending device, and then enters the receiving mode. The data receiving device has been performing channel activity detection. When the preamble is detected, it enters the receiving mode and receives The data sending device sends a handshake signal, and then sends a handshake response signal to the data sending device. After receiving the handshake response signal, the data sending device completes the handshake phase to realize the connection between the data sending device and the data receiving device.

In this embodiment, the device information of the data sending device includes the Media Access Control (MAC) address (or unique identification code) of the data sending device, the length of the second preamble in the data transmission stage, and other information. After the handshake is completed And before the data transmission starts, the data sending device and the data receiving device set the second preamble length according to the second preamble length information.

After the second preamble is set, it enters the data transmission stage. The data transmission stage uses the second preamble (the length of the second preamble is less than the length of the first preamble. For example, the second preamble can be the same as the first preamble. Minimum 6 bytes), which can reduce the transmission power consumption of the device and increase the speed of large amounts of data transmission.

If the length of the first preamble is L ₁ , the length of the second preamble is L ₂ (L ₁ >L ₂ ), and the effective length of each frame of data is L _data , then according to formula (8), under normal circumstances, the data The time required for transmission is

T _M1 ＝M×(L ₁ /L _data +1)×T _data (9)

Using the method shown in this disclosure, the time required for data transmission is

T _M2 = (L ₁ /L _data +1)×T _data +M×(L ₂ /L _data +1)×T _data (10)

When M is large enough, formula (10) can be simplified to

T _M2 = M×(L ₂ /L _data +1)×T _data (11)

Comparing formula (9) and formula (10), it can be obtained that the method shown in the present disclosure can significantly reduce the transmission time of a large amount of data transmission and reception, and due to the shortening of the transmission time, according to formula (7), the power consumption required for data transmission is power Multiplying with time, so the power consumption of data transmission will also be greatly reduced.

Fig. 3 is a schematic flowchart of a communication method according to an embodiment of the present disclosure. As shown in FIG. 3, in this embodiment, the communication method includes step 301 to step 303.

In this embodiment, step 301 includes: the data sending device sends a handshake signal including the first preamble to the data receiving device.

In an exemplary embodiment, the handshake signal may be a LoRa data packet.

As shown in Figure 4, the LoRa data packet includes: a preamble, an optional type of header, a data payload, and so on. Among them, the preamble is used to keep the receiving end synchronized with the input data stream. The function is to remind the receiving end that the data payload is about to be sent. Pay attention to receiving to avoid losing useful signals. After the current preamble is sent, the data payload will be sent immediately. Generally, the length of the preamble can be set between 10 and 65536 bits. Based on this mechanism, the preamble sending time of each LoRa data packet can be adjusted from a few milliseconds to tens of minutes. Using channel activity detection technology, the time to detect the preamble is within 0.4 milliseconds to 2 milliseconds.

In this embodiment, two preambles of different lengths are used: the first preamble in the handshake signal and the second preamble in the data signal. Wherein, the length of the first preamble is greater than the length of the second preamble.

In an exemplary embodiment, the handshake signal further includes a data payload portion, and the data payload portion includes at least one of the following: device information of the data sending device and length information of the second preamble.

Exemplarily, the device information of the data sending device may be a media access control address or unique identification code information of the data sending device.

In an exemplary embodiment, the transmission duration of the first preamble is greater than or equal to the sum of the channel activity detection duration and the sleep duration of the data receiving device.

As shown in Figure 5, assuming that the sleep duration is the first duration T _sleep , the channel activity detection duration is the second duration T _wk , and the transmission duration of the first preamble is the third duration T ₁ , then T ₁ ≥ T _wk + T _sleep . Since T _{1 is} greater than or equal to T _wk + T _sleep , in the third time period T ₁ , the data receiving device must be able to complete a channel activity detection, thereby ensuring that every first preamble sent by the data sending device can be used by the data receiving device Performing at least one channel activity detection also ensures that the data receiving device can receive the LoRa data packet sent by the data sending device in time, and carry out timely and effective interaction; in addition, because the first duration T _{sleep of the} data receiving device is greater than the second duration T _wk , the data receiving device is in a sleep state most of the time, which can greatly reduce the power consumption of the data receiving device.

Exemplarily, assuming that the length of the first preamble is 600 bits, and among the wireless communication parameters used by the data sending device, the spreading factor SF=7, the carrier frequency is 433 MHz, and the bandwidth is 125 kHz, then the transmission time length T ₁ of the first preamble is equal to _{At 618.75 milliseconds, the second time duration T wk} for a channel activity detection performed by the data receiving device is approximately 1.8 milliseconds. To satisfy T _wk + T _sleep ≤ T ₁ , the first time duration T _{sleep of the} data receiving device needs to be less than or equal to 616.95 milliseconds. For example, in an implementation manner, the first duration T _sleep =500 milliseconds can be set. It can be seen from this that the first time of the data receiving device can reach 500 milliseconds, and it only takes 1.8 milliseconds to wake up and perform channel activity detection, which can greatly save power consumption; in addition, a channel activity detection every 501.8 milliseconds will not miss the The detection of the first preamble with a sending time of 618.75 milliseconds can ensure that the data receiving device receives the LoRa data packet sent by the data sending device in time, and will not cause packet loss because the data receiving device is in a sleep state most of the time.

Step 302 includes: the data sending device receives a handshake response signal sent by the data receiving device.

In an exemplary embodiment, the handshake response signal may also be a LoRa data packet. The handshake response signal is used by the data receiving device to instruct the data sending device to successfully shake hands, and the data sending device can start sending data signals.

Step 303 includes: the data sending device sends a data signal including a second preamble to the data receiving device, where the length of the second preamble is smaller than the length of the first preamble.

In an exemplary embodiment, the data signal may also be a LoRa data packet.

In an exemplary embodiment, the second preamble may be the lowest N bytes or the highest N bytes of the first preamble, N is a natural number greater than 1 and less than M, and M is the The total number of bytes of the first preamble.

In an exemplary embodiment, when the data signal includes two or more frames, the data receiving device may only perform preamble detection on the first frame of data, so as to be awakened, and perform the preamble detection on the second frame and the first frame. The frame after the second frame is directly in the receiving state.

In an exemplary embodiment, the communication method may further include: the data sending device receiving a data reception success signal sent by the data receiving device. In this embodiment, a successful data reception signal is used to indicate the successful completion of this data transmission.

In an exemplary embodiment, the communication method may further include:

Receiving, by the data sending device, a reverse transmission signal sent by the data receiving device, where the reverse transmission signal includes device information of the data receiving device and length information of a third preamble;

The data sending device sends a reverse transmission response signal to the data receiving device;

The data sending device receives a data signal that includes a third preamble sent by the data receiving device, and the length of the third preamble is smaller than the length of the first preamble.

Fig. 6 is a schematic flowchart of another communication method according to an embodiment of the present disclosure. As shown in FIG. 6, in this embodiment, the communication method includes step 601 to step 603.

In this embodiment, step 601 includes: the data receiving device performs a channel activity detection of the second time length T _{wk after each sleep} of the first time length T sleep, and responds to the result of the channel activity detection being undetected The handshake signal including the first preamble sent by the data sending device goes to step 602; in response to the result of the channel activity detection being the detection of the handshake signal including the first preamble sent by the data sending device, the handshake signal includes The first preamble, the device information of the data sending device, and the length information of the second preamble, where the length of the second preamble is less than the length of the first preamble, go to step 603.

In this embodiment, the first duration T _{sleep is} greater than the second duration T _wk , and the _{sum of the first duration T sleep} and the second duration T _wk is less than or equal to the duration of the data sending device sending the first preamble.

Step 602 includes: the data receiving device continues to _sleep for the first duration T sleep;

Step 603 includes: the data receiving device sends a handshake response signal to the data sending device and receiving the data signal including the second preamble sent by the data sending device.

In an exemplary embodiment, the handshake response signal may also be a LoRa data packet. The handshake response signal is used by the data receiving device to instruct the data sending device to successfully shake hands, and the data sending device can start sending data signals.

In this embodiment, two preambles with different lengths are used: the first preamble in the handshake signal and the second preamble in the data signal, where the length of the first preamble is greater than the length of the second preamble.

As shown in Figure 5, assuming that the sleep duration is the first duration T _sleep , the channel activity detection duration is the second duration T _wk , and the transmission duration of the first preamble is the third duration T ₁ , then T ₁ ≥ T _wk +T _sleep . Since T _{1 is} greater than or equal to T _wk + T _sleep , in the third time period T ₁ , the data receiving device must be able to complete a channel activity detection, thereby ensuring that every first preamble sent by the data sending device can be used by the data receiving device Perform at least one channel activity detection, which also ensures that the data receiving device can receive the LoRa data packet sent by the data sending device in time, and carry out timely and effective interaction; in addition, because the first duration T _{sleep of the} data receiving device is greater than the channel activity detection For the second time period T _wk , the data receiving device is in a sleep state most of the time, which can greatly reduce the power consumption of the data receiving device.

Exemplarily, assuming that the length of the first preamble is 600 bits, and among the wireless communication parameters used by the data sending device, the spreading factor SF=7, the carrier frequency is 433 MHz, and the bandwidth is 125 kHz, then the transmission time length T ₁ of the first preamble is equal to _{At 618.75 milliseconds, the second time period T wk} for the data receiving device to perform a channel activity detection is about 1.8 milliseconds. To satisfy T _wk + T _sleep ≤ T _{1 , the first time period T sleep} for the data receiving device to perform one sleep must be less than or equal to 616.95 milliseconds. For example, in an implementation manner, the first duration T _sleep =500 milliseconds can be set. It can be seen from this that the first duration T _sleep of the data receiving device can reach 500 milliseconds, and it only takes 1.8 milliseconds to wake up and perform channel activity detection, which can greatly save power consumption; in addition, a channel activity detection every 501.8 milliseconds will not It will miss the detection of the first preamble with a sending time of 618.75 milliseconds, so as to ensure that the data receiving device receives the LoRa data packet sent by the data sending device in time, and will not cause packet loss because the data receiving device is in a sleep state most of the time Phenomenon.

In an exemplary embodiment, the data signal may also be a LoRa data packet.

In an exemplary embodiment, when the data signal includes two or more frames, the data receiving device may only perform preamble detection on the first frame of data, so as to be awakened, and perform the preamble detection on the second frame and the first frame. The frame after the second frame is directly in the receiving state.

In an exemplary embodiment, the communication method may further include: the data receiving device sending a data reception success signal to the data sending device. In this embodiment, a successful data reception signal is used to indicate the successful completion of this data transmission.

In an exemplary embodiment, the communication method may further include:

Sending, by the data receiving device, a reverse transmission signal to the data sending device, the reverse transmission signal including device information of the data receiving device and length information of the third preamble;

The data receiving device receives the reverse transmission response signal sent by the data sending device;

The data receiving device sends a data signal including a third preamble to the data sending device, and the length of the third preamble is smaller than the length of the first preamble.

FIG. 7 is a schematic flowchart of another communication method according to an embodiment of the present disclosure. As shown in FIG. 7, in this embodiment, the communication method includes step 701 to step 704.

In this embodiment, step 701 includes: the data sending device sends a handshake signal including the first preamble to the data receiving device.

In an exemplary embodiment, the handshake signal may be a LoRa data packet.

As shown in Figure 4, the LoRa data packet includes: a preamble, an optional type of header, a data payload, and so on. Among them, the preamble is used to keep the receiving end synchronized with the input data stream. The function is to remind the receiving end that the data payload is about to be sent. Pay attention to receiving to avoid losing useful signals. After the current preamble is sent, the data payload will be sent immediately. Generally, the length of the preamble can be set between 10 and 65536 bits. Based on this mechanism, the preamble sending time of each LoRa data packet can be adjusted from a few milliseconds to tens of minutes. Using channel activity detection technology, the time to detect the preamble can be completed within 0.4 milliseconds to 2 milliseconds.

In this embodiment, two preambles with different lengths are used: the first preamble in the handshake signal and the second preamble in the data signal, where the length of the first preamble is greater than the length of the second preamble.

In an exemplary embodiment, the handshake signal further includes a data payload portion, and the data payload portion includes at least one of the following: device information of the data sending device and length information of the second preamble.

In an exemplary embodiment, the transmission duration of the first preamble is greater than or equal to the sum of the channel activity detection duration and the sleep duration of the data receiving device.

As shown in Figure 5, assuming that the sleep duration is the first duration T _sleep , the channel activity detection duration is the second duration T _wk , and the transmission duration of the first preamble is the third duration T ₁ , then T ₁ ≥ T _wk + T _sleep . Since T _{1 is} greater than or equal to T _wk + T _sleep , in the duration T ₁ , the data receiving device must be able to complete a channel activity detection, thereby ensuring that every first preamble sent by the data sending device can be performed by the data receiving device at least One-time channel activity detection also ensures that the data receiving device can receive the LoRa data packet sent by the data sending device in time, and carry out timely and effective interaction; in addition, because the sleep duration T _{sleep of the} data receiving device is greater than the channel activity detection duration T _wk , The data receiving device is in a sleep state most of the time, which can greatly reduce the power consumption of the data receiving device.

Exemplarily, assuming that the length of the first preamble is 600 bits, and among the wireless communication parameters used by the data sending device, the spreading factor SF=7, the carrier frequency is 433 MHz, and the bandwidth is 125 kHz, then the transmission time length T ₁ of the first preamble is equal to _{At 618.75 milliseconds, the second time period T wk} for the data receiving device to perform a channel activity detection is about 1.8 milliseconds. To satisfy T _wk + T _sleep ≤ T _{1 , the first time period T sleep} for the data receiving device to perform one sleep must be less than or equal to 616.95 milliseconds. For example, in an implementation manner, the first duration T _sleep =500 milliseconds can be set. It can be seen from this that the first time of the data receiving device can reach 500 milliseconds, and it only takes 1.8 milliseconds to wake up and perform channel activity detection, which can greatly save power consumption; in addition, a channel activity detection every 501.8 milliseconds will not miss the The detection of the first preamble with a sending time of 618.75 milliseconds can ensure that the data receiving device receives the LoRa data packet sent by the data sending device in time, and will not cause packet loss because the data receiving device is in a sleep state most of the time.

Step 702 includes: the data receiving device performs a _{channel activity detection of the second duration T wk} every time after the first duration of dormancy; in response to the result of the channel activity detection, it is detected that the data sending device includes the first preamble. The data receiving device sends a handshake response signal to the data sending device, and the handshake signal includes the first preamble, the device information of the data sending device, and the length information of the second preamble.

In an exemplary embodiment, the handshake response signal may also be a LoRa data packet. The handshake response signal is used by the data receiving device to indicate that the data sending device has succeeded in the handshake, and the data sending device can start sending data signals.

Step 703 includes: the data sending device receives the handshake response signal sent by the data receiving device, and sends a data signal including a second preamble to the data receiving device, where the length of the second preamble is smaller than the length of the first preamble.

In an exemplary embodiment, the data signal may also be a LoRa data packet.

In an exemplary embodiment, when the data signal includes two or more frames, the data receiving device may only perform preamble detection on the first frame of data, so as to be awakened, and perform the preamble detection on the second frame and the first frame. The frame after the second frame is directly in the receiving state.

Step 704 includes: after receiving the data signal including the second preamble sent by the data sending device, the data receiving device continues to _sleep for the first duration T sleep.

In an exemplary embodiment, the communication method may further include: the data receiving device sending a data reception success signal to the data sending device. In this embodiment, a successful data reception signal is used to indicate the successful completion of this data transmission.

In an exemplary embodiment, the communication method may further include:

Sending, by the data receiving device, a reverse transmission signal to the data sending device, the reverse transmission signal including device information of the data receiving device and length information of the third preamble;

The data receiving device receives the reverse transmission response signal sent by the data sending device;

The data receiving device sends a data signal including a third preamble to the data sending device, and the length of the third preamble is smaller than the length of the first preamble.

FIG. 8 is a schematic structural diagram of a data sending device according to an embodiment of the present disclosure. The data sending device is generally a gateway server with no special requirements for power consumption. The data sending device in the embodiment of the present application can send data or receive data . As shown in FIG. 8, in this embodiment, the data sending device includes a first handshake module 801 and a first transmission module 802. The first handshake module 801 is configured to send a handshake signal including a first preamble to the data. The receiving device and receiving the handshake response signal sent by the data receiving device; the first transmission module 802 is configured to send a data signal including a second preamble to the data receiving device, and the length of the second preamble is less than that of the first preamble length.

In an exemplary embodiment, the handshake signal may be a LoRa data packet.

In this embodiment, two preambles with different lengths are used: the first preamble in the handshake signal and the second preamble in the data signal, where the length of the first preamble is greater than the length of the second preamble.

In an exemplary embodiment, the handshake signal further includes a data payload portion, and the data payload portion includes at least one of the following: device information of the data sending device and length information of the second preamble.

In an exemplary embodiment, the transmission duration of the first preamble is greater than or equal to the sum of the channel activity detection duration and the sleep duration of the data receiving device.

In an exemplary embodiment, the handshake response signal may also be a LoRa data packet. The handshake response signal is used by the data receiving device to instruct the data sending device to successfully shake hands, and the data sending device can start sending data signals.

In an exemplary embodiment, the data signal may also be a LoRa data packet.

In an exemplary embodiment, when the data signal includes two or more frames, the data receiving device may only perform preamble detection on the first frame of data, so as to be awakened, and perform the preamble detection on the second frame and the first frame. The frame after the second frame is directly in the receiving state.

In an exemplary embodiment, the first transmission module 802 is further configured to receive a data reception success signal sent by the data receiving device. In this embodiment, a successful data reception signal is used to indicate the successful completion of this data transmission.

In an exemplary embodiment, the first transmission module 802 is further configured to receive a reverse transmission signal sent by the data receiving device, and the reverse transmission signal includes the device information and the first transmission signal of the data receiving device. Length information of the three preambles; sending a reverse transmission response signal to the data receiving device; receiving the data signal containing the third preamble sent by the data receiving device, the length of the third preamble is less than the length of the first preamble .

9 is a schematic structural diagram of a data receiving device according to an embodiment of the present disclosure. The data receiving device is generally a mobile terminal that requires low power consumption. The data receiving device in the embodiment of the present application can send and receive data. As shown in FIG. 9, in this embodiment, the data receiving device includes a sleep control module 901, a channel activity detection module 902, and a second transmission module 903. The sleep control module 901 is set to elapse a first time period T each time. _{After sleep} , wake up the data receiving device and send a channel activity detection notification to the channel activity detection module 902; after receiving the sleep notification, _sleep for the first duration T sleep; the channel activity detection module 902 is set to receive the After the channel activity detection notification, a channel activity detection of the second duration T _wk is performed, and in response to not detecting the handshake signal including the first preamble sent by the data sending device, the dormancy notification is sent to the dormancy control module 901; in response to the detection When the handshake signal including the first preamble sent by the data sending device is sent, a data reception notification is sent to the second transmission module 903; the second transmission module 903 is set to send a handshake response signal to the data after receiving the data reception notification The sending device receives the data signal including the second preamble sent by the data sending device, and sends a sleep notification to the sleep control module 901 after the reception is completed. The handshake signal includes the first preamble and the device of the data sending device Information and length information of the second preamble, the length of the second preamble is smaller than the length of the first preamble.

In this embodiment, the first duration T _{sleep is} greater than the second duration T _wk , and the _{sum of the first duration T sleep} and the second duration T _wk is less than or equal to the duration of the data sending device sending the first preamble.

In an exemplary embodiment, the handshake response signal may also be a LoRa data packet. The handshake response signal is used by the data receiving device to indicate that the data sending device has succeeded in the handshake, and the data sending device can start sending data signals.

In this embodiment, two preambles with different lengths are used: the first preamble in the handshake signal and the second preamble in the data signal, where the length of the first preamble is greater than the length of the second preamble.

In an exemplary embodiment, the data signal may also be a LoRa data packet.

In an exemplary embodiment, when the data signal includes two or more frames, the second transmission module 903 may only perform preamble detection on the first frame of data, and perform preamble detection on the second frame and the second frame. The following frames do not perform preamble detection.

In an exemplary embodiment, the second transmission module 903 may be further configured to send a data reception success signal to the data sending device. In this embodiment, a successful data reception signal is used to indicate the successful completion of this data transmission.

In an exemplary embodiment, the second transmission module 903 may be further configured to send a reverse transmission signal to the data sending device, where the reverse transmission signal includes the device information of the data receiving device and the third preamble. Code length information; receiving a reverse transmission response signal sent by a data sending device; sending a data signal containing a third preamble to the data sending device, the length of the third preamble is smaller than the length of the first preamble.

The present disclosure also provides a communication system, including the above-mentioned data sending device and data receiving device.

The communication method and system, data sending device, and data receiving device of this embodiment implement data communication by adopting a long preamble combined with channel activity detection at the beginning of communication (ie, handshake phase); after the handshake is completed, in order to achieve For fast data transmission and reception, in the data transmission stage, a short preamble is used to communicate, so as to realize the rapid transmission and reception of a large amount of data transmission. In addition, due to the shortening of transmission time, the power consumption of data transmission will also be reduced.

The terms "include", "include", or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, product or equipment including a series of elements includes not only those elements, but also other elements that are not explicitly listed. Elements, or also include elements inherent to such processes, methods, commodities, or equipment. If there are no more restrictions, the element defined by the sentence "including a..." does not exclude the existence of other identical elements in the process, method, commodity, or equipment that includes the element.

Those skilled in the art should understand that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, this application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, this application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

The above descriptions are only examples of the present application, and are not used to limit the present application. For those skilled in the art, this application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the scope of the claims of this application.

Claims (10)

A communication method including: The data sending device sends a handshake signal including the first preamble to the data receiving device; Receiving, by the data sending device, a handshake response signal sent by the data receiving device; The data sending device sends a data signal including a second preamble to the data receiving device, and the length of the second preamble is smaller than the length of the first preamble. The communication method according to claim 1, wherein the handshake signal further includes device information of the data transmission device and length information of the second preamble. The communication method according to claim 1, wherein the second preamble is the lowest N bytes or the highest N bytes of the first preamble, N is a natural number greater than 1 and less than M, and M is The total number of bytes of the first preamble. The communication method according to any one of claims 1 to 3, further comprising: the data sending device receiving a data reception success signal sent by the data receiving device. A communication method including: The data receiving device performs a second-duration channel activity detection every time after the first-duration sleep period; In response to the result of the channel activity detection being that the handshake signal including the first preamble sent by the data sending device is not detected, the data receiving device continues to sleep for the first duration; In response to the result of the channel activity detection being the detection of the handshake signal including the first preamble sent by the data sending device, the data receiving device sends the handshake response signal to the data sending device and receives the handshake signal sent by the data sending device. The data signal including the second preamble; The handshake signal includes a first preamble, device information of the data sending device, and length information of a second preamble, where the length of the second preamble is smaller than the length of the first preamble. The communication method according to claim 5, after the data receiving device receives the data signal including the second preamble, the method further comprises: The data receiving device sends a data reception success signal to the data sending device. A communication method including: The data sending device sends a handshake signal including the first preamble to the data receiving device; The data receiving device performs a second-duration channel activity detection every time after the first-duration sleep; in response to the result of the channel activity detection being the detection of a handshake signal including the first preamble sent by the data-transmitting device, Sending, by the data receiving device, a handshake response signal to the data sending device, the handshake signal including a first preamble, device information of the data sending device, and length information of a second preamble; The data sending device receives the handshake response signal sent by the data receiving device, and sends a data signal including a second preamble to the data receiving device, where the length of the second preamble is smaller than the length of the first preamble; The data receiving device continues to sleep for the first duration after receiving the data signal including the second preamble sent by the data sending device. A data sending device includes a first handshake module and a first transmission module, wherein, The first handshake module is configured to send a handshake signal including a first preamble to a data receiving device, and receive a handshake response signal sent by the data receiving device; The first transmission module is configured to send a data signal including a second preamble to the data receiving device, and the length of the second preamble is smaller than the length of the first preamble. A data receiving device includes a sleep control module, a channel activity detection module, and a second transmission module, wherein: The sleep control module is configured to wake up the data receiving device and send a channel activity detection notification to the channel activity detection module every time after a first period of sleep has elapsed; after receiving the sleep notification, perform a first period of sleep; The channel activity detection module is configured to, after receiving the channel activity detection notification, perform a channel activity detection of a second duration, and in response to not detecting the handshake signal including the first preamble sent by the data sending device, send Dormancy notification to the dormancy control module; in response to detecting the handshake signal including the first preamble sent by the data sending device, send a data reception notification to the second transmission module; The second transmission module is configured to send a handshake response signal to the data sending device after receiving the data reception notification, and receive the data signal including the second preamble sent by the data sending device, and send sleep after the reception is completed Notifying the sleep control module that the handshake signal includes a first preamble, device information of the data sending device, and length information of a second preamble, where the length of the second preamble is smaller than the length of the first preamble. A communication system includes a data sending device and a data receiving device, the data sending device includes a first handshake module and a first transmission module, and the data receiving device includes a sleep control module, a channel activity detection module, and a second transmission module, in: The first handshake module is configured to send a handshake signal including a first preamble to a data receiving device, and receive a handshake response signal sent by the data receiving device; The first transmission module is configured to send a data signal including a second preamble to the data receiving device; The sleep control module is configured to wake up the data receiving device and send a channel activity detection notification to the channel activity detection module every time after a first period of sleep has elapsed; after receiving the sleep notification, perform a first period of sleep; The channel activity detection module is configured to, after receiving the channel activity detection notification, perform a channel activity detection of a second duration, and in response to not detecting the handshake signal including the first preamble sent by the data sending device, send Dormancy notification to the dormancy control module; in response to detecting the handshake signal including the first preamble sent by the data sending device, send a data reception notification to the second transmission module; The second transmission module is configured to send a handshake response signal to the data sending device after receiving the data reception notification, and receive the data signal including the second preamble sent by the data sending device, and send sleep after the reception is completed Notifying the sleep control module that the handshake signal includes a first preamble, device information of the data sending device, and length information of a second preamble, where the length of the second preamble is smaller than the length of the first preamble.

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