KR100695099B1 - Reverse link transmission speed control device using multiple forward control channels and its control method in high speed wireless communication system - Google Patents

Abstract

The present invention relates to an IMT-2000 system, and more particularly, to a reverse link by multiple forward control channels in a high speed wireless communication system for efficiently controlling a transmission speed for high speed wireless communication in a reverse link of a 1xEV-DO system. The present invention relates to a transmission rate control apparatus and a control method thereof.

The present invention provides a Reverse Activity (RA) channel receiver for receiving Reverse Activity Bit (RAB) information from each base station included in an active set of a terminal, and a SAB from each base station included in the active set of the terminal. SA (Secondary Activity) channel receiver for receiving Activity Bit) information, CRAB generator for generating combined RAB (CRAB) information using RAB information received from the RA channel receiver, SAB information received from the SA channel receiver A receiver including a CSAB generator for generating CSAB (Combined SAB) information, a random number generator for generating a random number value, a CRAB information value provided by the CRAB generator, a CSAB information value provided by the CSAB generator, and Transmission rate controller for determining the transmission rate by comparing the random number value provided by the random number generator and the transmission rate control probability, the transmission rate Data channel transmitter for transmitting data to the base station through the reverse link according to the transmission rate determined by the controller, RRI (Reverse Rate Indicator) information, which is the transmission rate information of the data channel provided by the transmission rate controller to the base station It consists of a transmitter including a channel transmitter.

Through the present invention, it is possible to control the stable transmission speed of the reverse link by adjusting the transmission speed of the reverse link based on a plurality of control information related to the reverse traffic load provided from the base station to the terminal, and obtain high transmission efficiency in the same communication environment. In addition, there is an effect of providing compatibility with the conventional system by implementing software by changing the operation of the upper layer without changing the physical layer channel structure in the conventional system.

Description

Apparatus and Method for Reverse Link Rate Control by Multiple Forward Link Control Channels in High-rate Wireless Communication System}

1 is a channel structure diagram of a 1xEV-DO system;

2 is a conceptual diagram of a general rate control in the reverse link,

3 is a general slot structure diagram of a forward link;

4 is a block diagram of a transmission rate control apparatus according to the prior art,

5 is a flowchart illustrating a control method of a transmission rate control apparatus according to the prior art;

6 is a block diagram of a transmission rate control apparatus according to the present invention,

7 is a flowchart illustrating a control method of a transmission rate control apparatus according to the present invention.

<Explanation of Signs of Major Parts of Drawings>

400, 600: CRAB generator 410, 610: Baud rate controller

420, 620: random number generator 430, 630: RA channel receiver

440, 640: data channel transmitter 450, 650: RRI channel transmitter

660: CSAB generator 670: SA channel receiver

The present invention relates to an IMT-2000 system, and more particularly, to a reverse link by multiple forward control channels in a high speed wireless communication system for efficiently controlling a transmission speed for high speed wireless communication in a reverse link of a 1xEV-DO system. The present invention relates to a transmission rate control apparatus and a control method thereof.

In general, the 1x EV-DO (1x Evolution-Data Only) system is one of the third generation mobile communication standards approved by the North American standardization organization called The Third Generation Partnership Project 2 (3GPP2). It is a system to support high speed packet data only at 1.25MHz which is frequency bandwidth of IS-95 (Interim Standard-95).

The 1xEV-DO system focuses on improving the forward speed of the forward link in consideration of the generation characteristics of the Internet traffic. The 1xEV-DO system supports up to 2.4Mbps and 153.6Kbps on the reverse link.

The 1xEV-DO system uses a different frequency band from the existing IS-95 system, but may use some of the frequency bands allocated for the IS-95 system.

Therefore, since the same wireless characteristics can be used, the same antenna system as the IS-95 can be used to support IS-95 and 1xEV-DO terminals operating in dual mode.

Techniques employed in the 1xEV-DO system include adaptive modulation and coding, mixed autotransmission requirements, fast channel feedback information, and multi-user detection.

1 shows a channel structure of the 1xEV-DO system.

As shown, the 1xEV-DO system includes a forward channel including a pilot channel, a medium access control (MAC) channel, a control channel, a traffic channel, and a traffic channel and an access channel. It includes a reverse channel.

The forward channel is a channel shared by all terminals in a cell managed by one base station, and the reverse channel is a channel dedicated to each terminal.

The basic unit of data transmission over the forward and reverse links is called a slot, and each slot is 1.666 ms long.

In addition, a unit consisting of 16 slots is called a frame, and each data packet transmitted from an upper layer is transmitted during one frame period.

The pilot channel of the forward channel is used for system acquisition, channel estimation and channel prediction.

The medium access control (MAC) channel of the forward channel is composed of a reverse activity (RA) channel and a reverse power control (RPC) channel, which is transmitted in parallel by a Walsh code, which is an orthogonal code, and has a total of 64 channels. It consists of.

At this time, one of the 64 channels is assigned to the RA channel, 59 channels are assigned to the RPC channel, the remaining four channels are left as a spare channel.

The RA channel provides 1 bit information of Reverse Activity Bit (RAB) indicating the traffic load of the reverse link to the UE, and the RPC channel transmits 1 bit information controlling the transmit power of the reverse traffic channel at 600 cycles per second. do.

The control channel basically includes a control message and a signaling message and in some cases is used to transmit user traffic.

The traffic channel is used to transmit user traffic within a data rate between 38.4 Kbps and 2.4576 Mbps. Since it is based on a time multiplexing technique, only one terminal can transmit data in a specific transmission period.

The access channel of the reverse channel is used to initiate communication between the terminal and the base station or to respond to a message transmitted to the terminal. The access channel includes a pilot channel and a data channel.

The traffic channel of the reverse channel is a channel used after the terminal and the base station are set up as a communication connection, and consists of a pilot channel, a MAC channel, an acknowledgment (ACK) channel, and a data channel therein.

The pilot channel is used for reverse channel estimation and coherent detection, and the MAC channel includes a data rate control (DRC) channel and a reverse rate indicator (RRI) channel.

The DRC channel is used so that the UE selects a base station having a good signal reception state of the forward link and a data transmission rate in consideration of the state of the forward channel and transmits the data to the 1xEV-DO system.

The RRI channel is used to inform the base station of the transmission rate of the data channel being transmitted, and the ACK channel is used to inform the base station whether the data received through the forward link is successful.

The data channel is used to support five types of transmission rates within the range of 9.6 Kbps to 153.6 Kbps. Since the modulation scheme and the spreading factor of symbols are the same, higher transmission power is required at a higher transmission rate. .

The five types of transmission rates used in the reverse data channel and the gain of transmission power compared to the pilot channel at each transmission rate are shown in Table 1 below.

symbol Baud rate (Kbps) Transmit Power Compared to Pilot Channel R (1) 9.6 3.75 R (2) 19.2 6.75 R (3) 38.4 9.75 R (4) 76.8 13.25 R (5) 153.6 18.50

Similarly, the transmission power of the DRC channel and the ACK channel is also transmitted based on the transmission power gain relative to the pilot channel. In general, the DRC channel transmits with a gain of -1.5 dB and the ACK channel transmits with a gain of 4.0 dB.

Since the RRI channel is transmitted in time multiplexed with the pilot channel, the transmit power gain is the same as that of the pilot channel in Table 1.

The pilot channel, MAC channel, ACK channel and data channel constituting the traffic channel of the reverse channel are transmitted in a code division state using a code having an orthogonality, except that the RRI channel in the MAC channel is a pilot channel. And time division state.

In the reverse traffic channel, the transmit power of the pilot channel, which is a reference of the transmit power of another channel, is applied to 1-bit RPC information transmitted by one of the forward channels, the RPC channel, to compensate for the fading phenomenon experienced by the wireless channel. Increase or decrease by 1 dB (or 0.5 dB).

In this case, the RPC information may be set based on a frame error rate of the corresponding UE or a signal to noise ratio (SNR) of the pilot channel.

2 is a conceptual diagram for controlling a transmission rate of a reverse traffic channel of a 1xEV-DO system.

As shown, each terminal can be seen to adjust the transmission rate using the RAB information transmitted by the base station and the unique probability model of the 1xEV-DO system.

That is, the RAB information transmitted by the base station includes the traffic load information of the reverse link, and the terminal receiving the information increases or decreases the transmission rate using a probability model and maintains the same transmission rate as before.

On the other hand, the base station may set the RAB information to 1 or 0. When the reverse traffic load exceeds a specific threshold Lth, a value of 1 is set and a value of 0 is set below.

In general, a base station uses a total receive power-to-noise ratio (ROT) obtained by dividing the total received power received by the base station by the power of the background noise as a reference for the traffic load. The unit is expressed in dB.

The ROT has a characteristic of increasing in proportion to transmission speeds of terminals, and generally shows excellent performance when viewed as a whole system when controlling at about 7dB.

However, if the value of the ROT exceeds a certain limit, the success rate of decoding of the data is significantly lowered. For example, if the reception ROT of the base station exceeds 10 dB, the success rate of the data is very low.

Therefore, each base station must efficiently control the traffic load of the reverse link in order to simultaneously increase data transmission efficiency and decoding success rate.

In addition, the set RAB information is transmitted to all terminals in a cell in a time unit called RABLength, and the time unit of the RABLength has one of 8/16/32/64 slots according to system configuration.

FIG. 3 shows a general slot structure in a forward link. It can be seen that various forward channels are multiplexed and transmitted in time. In particular, it can be seen that a MAC channel including RAB information is repeated four times in one slot.

Therefore, it can be estimated that RAB information is repeatedly transmitted at least several tens of times during the period of RABLength.

On the other hand, the terminal determines a new transmission rate each time a new packet is transmitted. In this case, as a parameter that plays an important role in adjusting the transmission rate together with the RAB information, p is a rate control probability stored in the terminal. And q values.

The transmission rate control probability is a parameter that is compared with a random number generated between 0 and 1 for a final determination of increasing or decreasing the transmission rate, and has a different value depending on the current transmission rate.

When the current transmission rate is R (i), the p value and the q value are respectively denoted by the transmission rate control probability p (i) (hereinafter p (i)) and the transmission rate control probability q (i) (hereafter q (i). Collectively, i = 1, 2, 3, 4, 5).

In addition, the p (i) value is used when the RAB = 0 is received to induce an increase in the reverse traffic load, and the q (i) value is used to distinguish the case where the RAB = 1 is received to reduce the reverse traffic.

The setting of the p (i) and q (i) values may be arbitrarily determined by the base station, and the base station may transmit new values to all terminals in the cell as needed, and the terminal may be based on the new values immediately after the reception. It will work.

In general, the p (i) value is set to a lower value as R (i) is larger, so that the higher the data transmission rate is, the higher the transmission rate is, and the q (i) value is larger as R (i). When set to a high value, if a traffic load is high, a terminal with a high transmission rate is first induced to lower the transmission rate.

That is, for example, p and q values are p = {p (1), p (2), p (3), p (4), p (5)} = {0.4, 0.2, 0.1, 0.05, 0 }, q = {q (1), q (2), q (3), q (4), q (5)} = {0, 0.1, 0.3, 0.6, 0.9} and the like.

4 is a block diagram of a transmission speed control apparatus of a terminal according to the prior art.

As shown, the transmission rate control device is composed of a receiver for receiving data on the forward link and a transmitter for transmitting data on the reverse link. Specifically, the receiver includes the RA channel receiver 430 and the CRAB generator 400. The transmitter includes a rate controller 410, a random number generator 420, a data channel transmitter 440, and an RRI channel transmitter 450.

Meanwhile, the RA channel receiver 430, the data channel transmitter 440, and the RRI channel transmitter 450 form a physical layer.

The RA channel receiver 430 may receive RAB information from a plurality of base stations. In order to independently receive RAB information transmitted from each base station, a plurality of RA channel receivers may be present in the physical layer of the receiver.

The number of RAB information that each terminal can receive at the same time is the same as the number of base stations in an active set managed by the terminal. The active set is a set of base stations having good signal transmission / reception sensitivity to a specific terminal. it means.

For reference, FIG. 4 assumes a case of receiving RAB information from a total of N base stations.

CRAB generator 400 is configured to calculate the CRAB (Combined RAB) information used to determine the transmission rate of the terminal from the plurality of RAB information delivered from the RA channel receiver 430 is provided to the transmission rate controller 410, RA The channel receiver 430 is configured to receive the RAB information transmitted from each base station and independently provide it to the CRAB generator 400.

The random number generator 420 is configured to generate a random number between 0 and 1, and the transmission rate controller 410 is provided with the CRAB information provided by the CRAB generator 400 and the random number provided by the random number generator 420 and the transmission rate. The transmission rate is determined by comparing the control probability.

The data channel transmitter 440 is configured to transmit data according to the transmission rate of the transmission rate controller 410, and the RRI channel transmitter 450 transmits RRI information, which is transmission rate information of data transmitted from the transmission rate controller, to the base station. It is configured to.

The operation description according to the above configuration is as follows.

RAB information sent from each base station in the active set is received through the corresponding RA channel receiver 430 of the receiver. The RAB information is read as 0 or 1 and input to the CRAB generator 400.

The CRAB generator 400 determines the value of CRAB information. If at least one of the input RAB information is set to 1, the CRAB value is set to 1, and if all RAB information is 0, the CRAB value is set to 0. do.

The transmission rate controller 410 determines the data transmission rate by comparing the random number generated in the range of 0 to 1 with the transmission rate control probability together with the CRAB information provided by the CRAB generator 400. .

The user data is transmitted through the data channel transmitter 440 according to the transmission rate determined by the transmission rate controller 410, and at the same time, the RRI information, which is the transmission rate information of the data, is transmitted to the base station through the RRI channel transmitter 450. .

5 is a flowchart illustrating a control method of a transmission speed control apparatus according to the prior art.

The baud rate controller selects R (1) as an initial baud rate for transmitting a packet (S500).

The transmission rate R (1) is also applied when transmitting a newly arrived packet after transmitting all packets in the buffer.

In the state where the initial transmission rate R (1) is selected, the terminal performs packet transmission (S502).

The terminal determines whether to increase or decrease the transmission rate by using the CRAB information in the transmission rate controller 410 each time after transmitting a packet using the initial transmission rate R (1) (S504).

The new transmission rate may be lowered or increased by one step based on the current transmission rate, and the actual increase or decrease is determined by comparing the transmission rate control probability and the random number to be generated next (S506 and S507).

When the CRAB information is 0, a comparison is performed between the random number generated by the random number generator 420 and p (i), which is a parameter of transmission rate control probability (S506).

At this time, when the random number is smaller than p (i), which is a parameter of the transmission rate control probability, the transmission rate is increased by one step, and when the current transmission rate is the maximum R (5), it is not increased any more (S508).

However, if the random number is larger than p (i), which is a parameter of transmission rate control probability, the packet is transmitted while maintaining the current transmission rate (S505).

The transmission rate determined by comparing p (i) with the generated random number is set as a new reference of the transmission rate used in the transmission of the next packet (S510).

On the other hand, when the CRAB value is 1, a comparison between the random number generated by the random number generator 420 and q (i), which is a parameter of transmission rate control probability, is performed (S507).

In this case, when the generated random number is smaller than q (i), which is a parameter of transmission rate control probability, the transmission rate is adjusted one step downward, and if the current transmission rate is R (1), the transmission rate is not decreased (S509).

However, if the generated random number is larger than q (i), which is a parameter of transmission rate control probability, the packet is transmitted while maintaining the current transmission rate (S505).

The transmission rate determined by comparing q (i) with the generated random number is set as a new reference of the transmission rate used when the next packet is transmitted (S510).

The data rate of the reverse link in the conventional 1xEV-DO system is determined by the RAB information transmitted from the base station to all terminals in the cell and the transmission rate control probability of the terminal.

The RAB information is composed of simple 1 bits, but is important information for determining the overall transmission speed of UEs in a cell managed by the base station. The RAB information compares the ROT calculated by the base station with a threshold value set by the base station itself to 0 or 1. Has a value.

However, since the ROT value is calculated as the total reception power ratio of the base station to the background noise power, the ROT value is influenced by various interferences received outside the cell as well as the power of the terminal in the cell.

Due to the influence of the interference, although the transmission state in the cell is not substantially bad, the value of the ROT can be increased, in this case, the base station transmits by setting the value of the RAB to 1 and the terminal unnecessarily transmits data There is a problem that results in lowering the hinder the overall performance of the reverse link.

The present invention has been made to solve the above problems, and the base station of the high-speed wireless communication system measures the power of the reverse traffic channel and transmits the related information SAB (Secondary Activity Bit) through the forward control channel, a plurality of terminals An apparatus for controlling a reverse link rate using multiple forward control channels and a control method thereof in a high-speed wireless communication system for improving the reverse link performance by determining a transmission rate in consideration of RAB information and SAB information received from a base station of The purpose is to provide.

Other objects and advantages of the invention will be described below and will be appreciated by the embodiments of the invention. Furthermore, the objects and advantages of the present invention can be realized by means and combinations indicated in the claims.

The present invention for achieving the above object is a RA (Reverse Activity) channel receiver for receiving RAB (Reverse Activity Bit) information from each base station included in the active set of the terminal, included in the active set of the terminal SA (Secondary Activity Bit) channel receiver for receiving SAB (Secondary Activity Bit) information from each base station, CRAB generator for generating Combined RAB (CRAB) information using the RAB information received from the RA channel receiver, the SA A receiver including a CSAB generator for generating CSAB (Combined SAB) information using SAB information received from a channel receiver, a random number generator for generating random numbers, a CRAB information value provided by the CRAB generator, and the CSAB generator The transmission rate is determined by comparing the provided CSAB information value, the random number value provided by the random number generator and the transmission rate control probability. A rate controller, a data channel transmitter for transmitting data to a base station through a reverse link according to the rate determined by the rate controller, and reverse rate indicator (RRI) information, which is information about a rate of data channels provided by the rate controller It consists of a transmitter including an RRI channel transmitter for transmitting to the base station.

In another aspect, the present invention is to select the initial transmission rate to transmit the packet to the base station, reading the CRAB information value and CSAB information value provided from the base station, determining the CRAB value and CSAB value according to the edition, the determined Up, down, or maintaining a transmission rate according to a combination of a CRAB value and a CSAB value; setting a new transmission rate according to an up, down, or maintenance adjustment of the transmission rate; and a packet according to the setting of the new transmission rate. Transmitting to the base station.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

6 is a block diagram of a transmission rate control apparatus in a reverse link according to the present invention.

As shown, the rate control apparatus includes a receiver including a CRAB generator 600, a CSAB generator 610, an RA channel receiver 630, and an SA channel receiver 670, a rate controller 610, and a random number generator. 620, a data channel transmitter 640, including a transmitter including an RRI channel transmitter 650, in the present invention, the terminal is preferably applied as the transmission rate control apparatus.

Meanwhile, the RA channel receiver 630, the SA channel receiver 670, the data channel transmitter 640, and the RRI channel transmitter 650 form a physical layer.

The CRAB generator 600 is configured to provide CRAB information used as input information of the speed controller 610, and the CSAB generator 660 is CSAB (Combined SAB) information used as input information of the speed controller 610. It is configured to provide.

The RA channel receiver 630 is configured to receive RAB information transmitted from each base station through an RA channel, and the SA channel receiver 670 is a secondary activity bit (SAB) transmitted from each base station through a SA (Secondary Activity) channel. Receive information.

The SAB information is additional 1-bit information different from the RAB, and is control information prepared to reduce noise effects due to ROT measurement.

Specifically, the SAB information is set to 0 or 1 according to the ratio of the total received power (IRP) and the total receivable power value of the base station for all the terminals communicating in the cell managed by the base station. It can be used as information indicating the traffic load of the reverse link with little influence from interference and noise from an external cell.

Each base station sets the SAB to 1 if the ratio of the IRP and the total power value is greater than or equal to the threshold Tth, and sets it to 0 otherwise.

For example, when the threshold Tth is set to 0.7, SAB = 1 when the ratio of the IRP and the total receiveable power value at the base station is 0.7 or more, and SAB = 0 when the ratio is less than 0.7.

In order to transmit the SAB information determined by the base station, an additional forward transport channel is required. Adding a separate channel to the conventional system causes a large change in the system structure and enormous investment cost is expected. We propose a scheme for transmitting SAB information without changing the channel structure.

In the conventional system, a total of 64 forward MAC channels are provided, and each MAC channel is designed to transmit only one bit of information periodically.

One of the 64 MAC channels is used for transmitting the RAB information, 59 are used for transmitting the RPC information of each terminal, and the remaining four channels are left unused and reserved.

Since the MAC channel is modulated and transmitted using Walsh codes having mutual orthogonality in transmission, the interference between MAC channels is very small, and each MAC channel is assigned a unique Walsh code identification number. Is called MACIndex, and MACIndex 4 is allocated to the RA channel, and MACIndex 5 to 63 are allocated to the RPC channel.

As a method of additionally transmitting SAB information using the forward MAC channel, the following two methods can be suggested.

First, one of the reserved MAC channels is used to transmit SAB information using one of MACIndex 0 to 3 channels that are not currently used and reserved.

The method has an advantage that the base station can easily transmit SAB information since collision with other channels does not occur.

Secondly, one of the 59 RPC channels is used for the transmission of SAB information. In fact, it is very unlikely that 59 RPC channels will be used in the 1xEV-DO system. use.

In this method, the RPC channel used for the SAB transmission is not used for the RPC information transmission of the UE, and the MAC channel having the corresponding MACIndex is not allocated during the initial connection with the UE.

The random number generator 620 is configured to generate a random value between 0 and 1, and the rate controller 610 may include the CRAB information provided by the CRAB generator 600, the CSAB information provided by the CSAB generator 660, and the random number generator ( The transmission rate is adjusted by using a comparison value between the random number value and the transmission rate control probability provided at 620.

The data channel transmitter 640 is configured to transmit data according to the transmission rate determined by the transmission rate controller 610, and the RRI channel transmitter 650 is configured to transmit RRI information, which is transmission rate information of data to be transmitted, to the base station. do.

The operation description according to the above configuration is as follows.

The RAB information and the SAB information, which are transmission rate control information, are received through the RA channel receiver 630 and the SA channel receiver 670 through the RA channel and the SA channel from the plurality of base stations in the active set.

The RAB information received through the RA channel receiver 630 is output as CRAB information through the CRAB generator 600 and input to the transmission rate controller 610.

In addition, the SAB information received through the SA channel receiver 670 is output as CSAB information through the CSAB generator 660 and input to the transmission rate controller 610.

As in the prior art, the CRAB information sets the CRAB value to 1 when the RAB value is set to 1 in at least one base station, and sets the CRAB value to 0 otherwise.

The generation of the CSAB value may be determined by autonomous control of the terminal based on a plurality of SAB information. In the present invention, the CSAB value is set to a plurality of values from among the plurality of received SAB information.

For example, if the base station with SAB = 1 is equal to or greater than the base station with SAB = 0, the CSAB value is set to 1. On the contrary, if the base station with SAB = 0 is larger than the base station with SAB = 1, the CSAB value is set to 0. do.

In this case, unlike the CRAB setting method, the CSAB value is set by a majority vote because the change in the IRP value does not have a significant effect on the performance degradation of the system compared to the change in the ROT.

For example, if the ROT of a base station having RAB information set to 1 increases due to an increase in transmission speed of a terminal, it is more likely to cause an overall decrease in performance of a corresponding cell.In the case of an IRP value, an increase in an IRP value of a corresponding base station is increased. It is not necessarily the result of system degradation.

In addition, the random number generator 620 generates a random number within a range of 0 to 1 and provides the random number to the transmission rate controller 610.

The transmission rate controller 610 determines the transmission rate of the data by using the input CRAB information, CSAB information, a comparison value of the random number value and the transmission rate control probability.

Data to be transmitted is transmitted to the base station through the data channel transmitter 640 according to the transmission rate determination of the transmission rate controller 610, and at the same time, the RRI information, which is the transmission rate information of the data, is transmitted through the RRI channel transmitter 650. Is sent to.

7 is a flowchart illustrating a control method in a terminal for determining a transmission speed of a reverse link according to the present invention.

The transmission rate controller 610 of the terminal selects R (1) as an initial transmission rate for transmitting a packet (S700).

Meanwhile, the transmission rate R (1) is also applied to the initial transmission rate when transmitting a newly arrived packet after transmitting all packets in the buffer.

In the state where the initial transmission rate R (1) is selected, the terminal performs initial packet transmission (S702).

After the packet transmission is performed by the initial rate R (1), the rate controller 610 uses the combination of the CRAB information value provided by the CRAB generator 600 and the CSAB information value provided by the CSAB generator 660 in the new rate. Determine (S704).

That is, the new transmission rate is selected by identifying the load state of reverse traffic through the combination of the CRAB information value and the CSAB information value.

First, when the CRAB information value is 0 and the CSAB information value is 0, the base station in the active group determines that there is sufficient margin in the traffic load, so that the parameters of the random number value generated by the random number generator 620 and the transmission rate control probability are determined. A comparison of p (i) is performed to determine whether the transmission speed is increased (S705).

At this time, when the generated random number is smaller than p (i), which is a parameter of transmission rate control probability, the transmission rate is adjusted up one step, and when the current transmission rate is R (5), which is the maximum value, it is not increased any more. (S706).

The determined new transmission rate becomes a new reference of the transmission rate used in the transmission of the next packet (S712), and is used as a new transmission rate in the transmission of the next packet (S702).

However, when the generated random number is larger than p (i), which is a parameter of transmission rate control probability, the current transmission rate is maintained as it is (S707), and the packet is transmitted using the same transmission rate when the next packet is transmitted. (S702).

If the CRAB information value is 0 and the CSAB information value is 1, it can be considered that there is a margin of ROT for the base stations in the active set, but the increase in IRP increases as the transmission rate increases. Since the sum of the received powers exceeds the threshold but the ROT value is not large, the normal decoding is possible. From the aspect of transmission rate control, it is determined that the traffic load is close to the target value and the current transmission rate is maintained as it is (S707). In the case of transmission of the data using the same transmission rate as the current transmission (S702).

If the CRAB information value is 1 and the CSAB information value is 0, the ROT value for the base stations in the active set exceeds the threshold but can be regarded as a phenomenon caused by the effect of instantaneous noise because there is room in IRP. In terms of transmission rate control, it is determined that the traffic load is close to the target value and maintains the current transmission rate as it is (S707), and the next packet is transmitted using the same transmission rate as the current (S702).

But. When the CRAB information value is 1 and the CSAB information value is 1, it is determined that the load of the ROT and IRP values is large for the base stations in the active set, so that the random number value generated by the random number generator 620 and the transmission rate control probability A comparison of the parameter q (i) is performed to determine whether the transmission speed is reduced (S709).

In this case, when the generated random number is smaller than the parameter q (i) of the transmission rate control probability, the transmission rate is adjusted one step downward, and when the current transmission rate is the minimum value R (1), it is no longer reduced (S710). ).

The determined new transmission rate becomes a new reference of the transmission rate used in the transmission of the next packet (S712), and is used as a new transmission rate in the transmission of the next packet (S702).

However, when the generated random number is larger than q (i), which is a parameter of transmission rate control probability, the current transmission rate is maintained as it is (S707), and the packet is transmitted using the same transmission rate when the next packet is transmitted. (S702).

Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art to which the present invention pertains can implement the present invention in other specific forms without changing the technical spirit or essential features, The examples are to be understood in all respects as illustrative and not restrictive.

In addition, the scope of the present invention is specified by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are included in the scope of the present invention. Should be interpreted as

As described above, the apparatus for controlling reverse link transmission rate by the multiple forward control channels and the control method thereof in the high speed wireless communication system according to the present invention are based on a plurality of control information related to the reverse traffic load provided from the base station to the terminal. By controlling the transmission speed of the link, it is possible to control the stable transmission speed of the reverse link and to obtain high transmission efficiency in the same communication environment, and also to operate the upper layer without changing the physical layer channel structure in the conventional system. By changing the implementation in software, there is an effect of providing compatibility with the conventional system.

Claims (12)

RA channel receiver for receiving RAB information from each base station included in the active set of the terminal, SA channel receiver for receiving SAB information from each base station included in the active set of the terminal, from the RA channel receiver A receiver comprising a CRAB generator for generating CRAB information using the received RAB information, and a CSAB generator for generating CSAB information using SAB information received from the SA channel receiver; And The transmission rate is determined by comparing a random number generator for generating a random value, a CRAB information value provided by the CRAB generator, a CSAB information value provided by the CSAB generator, and a random number value provided by the random number generator and a transmission rate control probability. A transmission rate controller for transmitting data, a data channel transmitter for transmitting data to a base station through a reverse link according to the transmission rate determined by the transmission rate controller, and transmitting RRI information, which is transmission rate information of the data channel provided by the transmission rate controller, to the base station. Transmitter comprising an RRI channel transmitter for Reverse link transmission rate control apparatus by multiple forward control channels in a high-speed wireless communication system comprising a. The method of claim 1, The SAB information is a high-speed wireless communication, characterized in that for setting the ratio of the total reception power for all terminals communicating with the base station and the total receivable power value of the base station in a cell managed by a specific base station compared with a threshold Reverse link rate control system using multiple forward control channels in a system. The method according to claim 1 or 2, The SAB information is a reverse link transmission rate control apparatus by multiple forward control channels in the high-speed wireless communication system, characterized in that 1-bit additional forward control information to inform the terminal of the traffic load of the reverse link. The method according to claim 1 or 2, The SAB information is transmitted by using one of the forward spare MAC channels or by using any one of the forward RPC channels used for other purposes. Reverse link transmission rate control device. The method of claim 4, wherein In the case of transmitting the SAB information through a specific RPC channel, the reverse link transmission rate by multiple forward control channels in the high-speed wireless communication system, characterized in that the allocation of the RPC channel for the purpose of power control of the terminal is prohibited. Control unit. a) selecting an initial transmission rate and transmitting a packet to a base station; b) reading the RAB information value and SAB information value provided from the base station; c) determining a CRAB value and a CSAB value according to the reading; d) increasing, decreasing, or maintaining a transmission rate according to a combination of the determined CRAB value and CSAB value; e) setting a new transmission rate according to the upward, downward or maintenance adjustment of the transmission rate; And f) transmitting a packet to a base station according to the setting of the new transmission rate; and a reverse link transmission rate control method using multiple forward control channels in a high speed wireless communication system. The method of claim 6, After step b) above, b-1) determining the CSAB value according to a plurality of values of the SAB information value. The method of claim 6, After step c), c-1) When the CRAB value and the CSAB value are each 0, it is determined that there is room in reverse traffic load, and the generated random number value is compared with the transmission rate control probability p (i) to determine the generated random number value. If the transmission rate is less than the probability p (i), the method further comprising the step of adjusting the transmission rate of the reverse link transmission rate by the multiple forward control channel in a high-speed wireless communication system. The method of claim 8, If the generated random number is greater than the transmission rate control probability p (i), maintaining the current transmission rate, further comprising reverse link transmission rate by multiple forward control channels in a high speed wireless communication system. Control method. The method of claim 6, After step c), c-2) when the CRAB value is 0 and the CSAB value is 1, or when the CRAB value is 1 and the CSAB value is 0, determining that the reverse traffic load is close to a target value and maintaining the current transmission rate. A reverse link transmission rate control method using multiple forward control channels in a high speed wireless communication system comprising a. The method of claim 6, After step c), c-3) When the CRAB value and the CSAB value are each 1, it is determined that a reverse traffic load is large, and a comparison between the generated random number value and the transmission rate control probability q (i) results in the transmission of the random number value. And adjusting the transmission rate downward when the rate control probability q (i) is smaller than the rate control probability q (i). The method of claim 11, If the generated random number is larger than the transmission rate control probability q (i), maintaining the current transmission rate, and further comprising reverse link transmission rate by multiple forward control channels in the high speed wireless communication system. Control method.

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