KR100996079B1 - Method and apparatus for controlling reverse traffic-to-pilot power ratio in mobile communication system - Google Patents

Abstract

According to the present invention, different packet data can be transmitted in the reverse direction, and TPR values for the transmission of different packet data are mapped to each transmission rate that can be set in the reverse direction, and the criteria determined in consideration of the type and number of services for each transmission rate. In a mobile communication system having a TPR table having a TPR value, when transmitting different packet data in a reverse direction, in a TPR control apparatus, when receiving packet data received from a mobile terminal, the TPR table may be configured according to the type of the received packet data. After performing backward scheduling using a reference TPR value, a base station transmitting TPR control information determined according to the scheduling result to the mobile terminal through a TPR control channel, and determining whether to increase or decrease TPR when receiving TPR control information from the base station. A packet previously transmitted from the TPR table. A reference TPR value of the next packet data is determined from the TPR table according to the TPR control information after checking a reference TPR value corresponding to a data rate of the data, and among the determined TPR values and TPR values of the next type of packet data to be transmitted. And a mobile terminal for determining a transmission rate corresponding to the TPR value closest to the determined TPR value, and configuring the packet data to be transmitted at the determined transmission rate and transmitting the power according to the TPR value.

Description

METHOD AND APPARATUS FOR CONTROLING REVERSE TPR IN MOBILE TELECOMMUNICATION SYSTEM}             

1 is a block diagram showing the structure of a mobile communication system for reverse TPR control according to an embodiment of the present invention;

2 is a flowchart illustrating an operation of a mobile terminal for controlling reverse TPR according to an embodiment of the present invention;

3 is a flowchart illustrating an operation of a base station for processing packet data transmitted at a reverse rate determined by a mobile station according to an embodiment of the present invention.

The present invention relates to a method and apparatus for controlling a reverse traffic to pilot power ratio (hereinafter referred to as a TPR) in a mobile communication system. In particular, two mobile communication systems require different quality of service (QoS) requests from a single mobile terminal. If more than one service is provided relates to a reverse TPR control method and apparatus.

Typically, a mobile communication system using a code division multiple access (CDMA) scheme supports multimedia services using the same frequency band and allows a plurality of mobile terminals to simultaneously transmit data to a base station. At this time, the identification of the mobile terminals is made through a spreading code uniquely assigned to each mobile terminal.

Data transmission in the direction, i.e., reverse direction, from the mobile terminal to the base station is performed through the Reverse Packet Data Channel (R-PDCH) in units of physical layer packets (PLPs), and the length of the packet is fixed. do. The data rate of a packet may vary from packet to packet, and the data rate of each packet is determined by the power of the mobile terminal transmitting the packet, the total amount of data to be transmitted, and the forward rate control channel (RCCH). It is controlled by a rate control bit (RCB) provided from the base station through.

The base station determines the reverse rate of the mobile terminals by using a rise of thermal (RoT) representing the total received power to the thermal noise, or a load obtained from the received signal to noise ratio (SNR) of the mobile terminals in service. do. In the case of using RoT, the reverse rate of the mobile terminal is controlled so that the RoT of the mobile terminal approaches the reference RoT. On the other hand, if RoT is not available, the reverse rate of the mobile terminal is controlled so that the load of the mobile terminal is close to the reference load. That is, the base station determines whether to increase, decrease or maintain the data rate of each mobile terminal in consideration of RoTs of all mobile terminals in service, the total amount of data to be transmitted, and the power state. When the reverse rate control of the mobile terminal is efficiently performed, the throughput of the entire system can be increased.

Information for controlling the data rate of the mobile terminal determined by the base station is transmitted to the mobile terminal in the form of a reverse control bit (hereinafter referred to as RCB). Herein, the operation of the RCB will be described. When the RCB value received from the base station is '+1' indicating an increase, the mobile station increases the reverse rate in the next transmission interval, and if '-1' indicates a decrease, The reverse rate is reduced in the transmission interval, and if it is '0', the reverse rate in the next transmission interval is maintained as before.

On the other hand, the base station and the mobile station typically promises a TPR (Traffic to Pilot Power Ratio) value in advance for each data rate of the reverse packet data channel (R-PDCH). An example of such pre- promised RCB values is shown in Table 1 below.

Data Rate of R-PDCH [kbps] TPR of R-PDCH [dB] 19.2 1.00 38.4 3.75 76.8 6.50 153.6 8.00 307.2 9.00 460.8 10.00 614.4 10.00 921.6 10.00 1228.8 10.00

The meaning of the TPR used herein is a value representing the power ratio of the traffic channel to the power of the pilot channel of the mobile terminal. Therefore, when the base station grants a specific data rate to the mobile terminal, the mobile station performs reverse traffic transmission at the set rate. For the data transmitted at the transmission rate, the channel gain of the corresponding traffic channel is set and transmitted as shown in Table 1 below.

This will be described in more detail by way of example. First, when the reverse data rate of the mobile terminal is set to 153.6kbps, the channel gain of the traffic channel to be used when transmitting data becomes 8.0 dB as shown in Table 1 above. If the base station controls to change the transmission rate of the mobile terminal to 307.2 kbps while transmitting data using the transmission rate and the power gain value for the traffic channel, the mobile terminal generally transmits the data at the transmission rate. In this case, referring to Table 1, the gain of the traffic channel according to the set transmission rate is changed to a value of 9.0 dB so that the data gain is transmitted.

As described above, when the mobile station needs to change from a rate of 153.6 kbps to a rate of 307.2 kbps, the base station controls the rate by setting the value of RCB to '+1' indicating a rate increase. The process of controlling the reverse traffic transmission of the mobile station in the base station is called scheduling. The base station controls the mobile station to change the channel rate of the traffic channel while changing the reverse rate of the mobile station according to the scheduling. Therefore, the base station has a table as shown in Table 1, thereby detecting the transmission rate of each mobile terminal, and can calculate a reverse load accordingly.                         

However, in a specific system, two or more services requiring different quality of service (QoS) may be provided to one mobile terminal. In this case, the TPR values used for the respective services are different. In addition, a case may occur where data for each service arriving at the mobile terminal is randomly generated. Due to these phenomena, there is a problem that the base station cannot know in advance which service the packet data will be transmitted to. This results in the inability to calculate the correct load from the base station, resulting in the inability to perform efficient reverse data rate control. Therefore, if the above problem is repeated, the service quality may be reduced or other services may not be provided because the load of the base station is not controlled.

Accordingly, an object of the present invention is to provide a method and apparatus for efficiently controlling reverse TPR when two or more services requiring different QoS are serviced in one mobile terminal.

Another object of the present invention is to provide a reverse TPR control method and apparatus in a situation where the base station does not know in advance the type of traffic transmitted by the mobile terminal when two or more services requiring different QoS are serviced by one mobile terminal. In providing.

Another object of the present invention is to provide a reverse TPR control method and apparatus in a situation where the base station does not know in advance the type of traffic transmitted by the mobile terminal when the TPR value used for each service is different.

The apparatus for achieving the above object of the present invention can transmit different packet data in the reverse direction, the traffic to pilot rate (TPR) for the transmission of different packet data for each transmission rate that can be set in the reverse direction (TPR) In a mobile communication system having a TPR table having a value mapped thereto and having a reference TPR value determined in consideration of the type and number of services for each transmission rate, the base station in the TPR control apparatus when transmitting different packet data in the reverse direction, In case of receiving packet data from the mobile station, after performing reverse scheduling using the reference TPR value of the TPR table according to the type of the received packet data, the TPR control information determined according to the scheduling result is transmitted through the TPR control channel. A base station transmitting to a mobile terminal and the base station To determine whether the TPR is increased or decreased when receiving the TPR control information, examines a reference TPR value corresponding to the transmission rate of the packet data previously transmitted in the TPR table, and then determines whether to use the next packet data from the TPR table according to the TPR control information. Determine a reference TPR, determine a transmission rate corresponding to the TPR value closest to the determined TPR value among the determined TPR value and TPR values for the next type of packet data to be transmitted, and configure the packet data to be transmitted at the determined transmission rate; And a mobile terminal transmitting with power according to the TPR value.

In addition, a method for achieving the objects of the present invention can transmit different packet data in the reverse direction, TPR value for the transmission of different packet data is mapped to each transmission rate that can be set in the reverse direction, the service for each transmission rate In a mobile communication system having a TPR table having a reference TPR value determined in consideration of the type and number of the TPR, in a TPR control method for transmitting different packet data in a reverse direction, the received packet data received from the mobile terminal is received. Performing backward scheduling using a reference TPR value of the TPR table according to the type of packet data, and then transmitting TPR control information determined according to the scheduling result to the mobile terminal through a TPR control channel; Determine whether the TPR is increased or decreased when receiving control information, After checking the reference TPR value corresponding to the transmission rate of the previously transmitted packet data in the TPR table, the reference TPR of the next packet data is determined from the TPR table according to the TPR control information, and the determined TPR value and the next packet to be transmitted are determined. Determining a transmission rate corresponding to the TPR value closest to the determined TPR value among the TPR values for the type of data, and configuring the packet data to be transmitted at the determined transmission rate and transmitting the power according to the TPR value. It features.

In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may vary according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

1 is a block diagram illustrating a structure of a mobile communication system for reverse rate control according to an embodiment of the present invention.

Referring to FIG. 1, a mobile communication system includes a mobile terminal 10 and a base station (BS) 20, and the base station system 20 is connected to the mobile station 10. And a base station transceiver (BTS) 21 for performing wireless data communication, and a base station controller 22 for controlling the base station transceiver 21. Hereinafter, the base station system will be collectively referred to as a base station (BS) 20.

 Two or more services that provide different QoS to one mobile terminal 10 are provided, and the TPR value used for each service is different for controlling reverse TPR, and for each service generated in the mobile terminal 10, When the data is randomly generated and the base station 20 cannot know in advance which service the mobile terminal 10 will send a packet for, the base station 20 controls the reverse TPR.

The base station 20 transmits a signaling message to the mobile terminal 10 through a signaling message during a call setup process or when a new service is opened in the middle of a call, or when the base station 20 determines that the base station 20 is needed. The base station 20 gives a reference table that is a reference for the TPR values to be controlled by the base station 20 and controls the reverse TPR based on the table.                     

The base station 20 controls the backward TPR based on the smallest TPR value among the values closest to, or greater than or equal to, the TPR value used for the latest reverse packet data transmission received from the mobile terminal 10. . The TPR control result is transmitted to the mobile terminal 10 in the form of TPRCB.

The mobile terminal 10 having received the control information (for example, TPRCB) obtains a TPR value allowed for the mobile terminal 10, and the mobile terminal 10 has previously been used in the reference table. The received TTPRCB is interpreted based on the TPR value that is closest to, or greater than or equal to, the TPR value used for the transmitted packet data channel, to interpret the TPR value allowed for the packet data channel.

A data transmission rate of a newly transmitted packet is determined within the allowed TPR value range, and a TPR table corresponding to a service type of a newly transmitted packet is used in determining the data transmission rate. An example of the TPR table is described below. It is shown in Table 2.

Data Rate of R-PDCH [bps] TPR of
Service 1 [dB] TPR of
Service 2 [dB] Reference TPR 19.2 1.00 2.76 1.96 38.4 3.85 5.61 4.81 76.8 6.70 8.46 7.67 153.6 9.40 11.16 10.37 307.2 12.00 13.76 12.97 460.8 13.60 15.36 14.57 614.4 14.40 16.16 15.37 921.6 16.10 17.86 17.07 1228.8 17.40 19.16 18.37

Table 2 shows a base station 20 through a signaling message or a base station 20 when a new service starts in the middle of a call setup process or in the middle of a call, according to an exemplary embodiment of the present invention. ) Is a reference table that becomes a reference for the TPR values to be controlled by the base station 20 to the mobile terminal 10 through a signaling message when it is determined that it is necessary. In Table 2, the second and third columns indicate TPR values used when packet data for each service 1 and service 2 is transmitted. The fourth column of Table 2 shows the TPR values that are used as a reference for the control when the base station 20 controls the TPR of the mobile terminal 10 according to the preferred embodiment of the present invention. As described above, when the mobile terminal 10 transmits a packet for service 1 at a specific point in time, the TPR values defined in the second column of Table 2 are used. As described above, when the mobile terminal 10 transmits a packet for service 2 at a specific time point, TPR values defined in the second column of Table 2 are used. As described above, the mobile terminal 10 uses the TPR values defined in the third row of Table 2 in the process of receiving the TPRCB from the base station 20 and interpreting the TPR values allowed thereto. For example, assume that the mobile terminal 10 transmits a packet for service 1 at a specific time point using a TPR of 9.4 dB at a transmission rate of 153.6 kbps. In the process of scheduling the mobile terminal 10 in the base station 20 that has received the packet data, the TPR of 9.4 dB used for transmission of the received packet and 10.37 dB, which is the closest value in the reference table, is the reference of the control. Becomes Accordingly, the base station 20 scheduler again allows the mobile terminal 10 the same TPR of 10.37 dB in the TPR that is the reference of 10.37 dB, or allows a TPR of 7.67 dB lower than this, or Determine whether to allow 12.97 dB of TPR. According to the scheduling result, the base station 20 transmits TPRCBs of '0', '-1' and '+1' to the mobile terminal 10. The mobile terminal 10 receives the TPRCB from the base station 20 to generate the TPRCB based on a TPR of 9.4 dB previously transmitted by the mobile station 10 and 10.37 dB, which is the closest value among the reference TPR values shown in Table 2. To judge. That is, if the TPRCB is '0', '-1', '+ 1', it is determined that the TPR of 10.37 dB, 7.67 dB, and 12.97 dB is allowed to each. The mobile terminal 10 determines the TPR value allowed for the mobile station 10 and determines the TPR value and the data rate of the next transport packet within the allowable TPR value range. For example, if the TPR allowed for the mobile terminal 10 is 12.97 dB, and the packet data to be transmitted next by the mobile terminal 10 is a packet for service 2, the mobile terminal 10 may be configured as described in <Table 2>. In the third column of>, the packet for the service 2 can be transmitted at 11.16 dB, which is the largest value among the values smaller than 12.97 dB, that is, 153.6 kbs.

In the above description, the TPR received from the mobile station 10 or the TPR value used by the mobile station 10 in the previous packet data transmission in the process of determining the reference TPR by the base station 20 and the mobile station 10. Although the example of setting the closest value to a reference value has been given, the same procedure and method are used instead of the closest value, but the TPR received from the mobile terminal 10 or the mobile terminal 10 in the previous packet data transmission. Note that the smallest value may be based on the same or greater than the TPR value used.

In addition, the reference TPR values corresponding to the fourth column in Table 2 are examples using values that are averages of TPR values for service 1 and service 2. Unlike Table 2, in setting the reference TPR values, any value may be used. For example, in setting the reference TPR values, TPR values for either service 1 or service 2 may be set as the reference TPR values. Alternatively, values such as 0 dB, 2 dB, 4 dB... Which have nothing to do with the TPR values used in the service 1 or the service 2 may be set as TPR reference values.

2 is a flowchart illustrating the operation of the mobile terminal 10 for controlling the reverse TPR according to an embodiment of the present invention.

In step 210, the mobile terminal 10 transmits packet data to the base station 20 through a reverse packet data channel (R-PDCH). In step 220, the mobile terminal 10 stores a service type of the transmitted packet data. Thereafter, in step 230, the mobile terminal 10 receives reverse data rate control information, for example, TPRCB, from the base station 20. Then, in step 240, the mobile terminal 10 selects a TPR table suitable for the service type of the stored packet data, and in step 250, the mobile terminal 10 is allowed to the mobile terminal 10 according to the received TPRCB in the selected TPR table. Determine the TPR value.

When the TPR value is determined, in step 260, a TPR table corresponding to the service type of the next packet to be transmitted is selected. Then, in step 270, the mobile terminal 10 determines the data rate and the TPR in the TPR table determined according to the next packet service type to be transmitted within the determined maximum allowable TPR value.

This operation will be described in detail with reference to Table 2, for example. In step 210, the mobile terminal 10 transmits packet data corresponding to service 1 having a data rate of 153.6 kbps to the base station 20. At this time, the TPR value used for the packet transmission is 9.4 dB. When the TPRCB received in step 230 is +1 (up), the mobile terminal 10 is closest to 9.4 dB, which is a TPR value used for a previously transmitted packet among the reference TPR values of Table 2, in step 240. The value is taken as a criterion for interpreting the TPRCB. Referring to <Table 2>, the value closest to the 9.4 dB among the reference TPR values is 10.37 dB, and since the TPRCB is '+1', the TPRCB allowed for the mobile terminal 10 is the reference TPR value. Among them, 12.97 dB is higher than 10.37 dB. If the service type of the packet data to be newly transmitted corresponds to service 2, the mobile terminal 10 determines to use the third column in Table 2, that is, TPR values defined for service 2. Since the allowed TPR is 12.97 dB, the maximum data rate that can be transmitted within the 12.97 dB becomes 153.6 kbps using 11.16 dB. Accordingly, the mobile terminal 10 transmits packet data for service 2 within the 153.6 kbps.

An operation of a base station processing packet data transmitted at a transmission rate determined by such an operation will be described with reference to the accompanying drawings.

3 is a flowchart illustrating an operation of a base station for processing packet data transmitted at a reverse rate determined by a mobile station according to an embodiment of the present invention.

In step 310, the base station 20 receives packet data through the packet data channel from the mobile terminal 10. Then, the TPR value closest to the TPR value for the transmission of the packet received in step 320 is determined in the reference table of Table 2. In step 330, the base station 20 performs scheduling based on the TPR value determined in step 320. Then, in step 340, the base station 20 transmits a TPRCB value to the mobile terminal 10 through a TPR control channel (TPRCCH) according to the scheduled result.

In the above-described embodiments of the present invention, a case in which two services requiring different quality of service (QoS) are opened in one mobile terminal is described. However, three or more services requiring different quality of service are provided. It should be noted that embodiments of the present invention as described above may be applied even when opened.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, when two or more services requiring different quality of service are serviced by one mobile terminal, the present invention relates to a service of packet data to be newly transmitted based on a TPR value determined for a service of recently received packet data. By selecting a TPR value, the data rate can be controlled more efficiently.                     

In addition, the same effects as described above also apply when the TPR value used for each service is different and when data for each service arriving at the mobile terminal is randomly generated.

Claims (2)

Different packet data can be transmitted in the reverse direction, and a traffic to pilot power ratio (TPR) value for transmission of different packet data is mapped to each of the transmission rates that can be set in the reverse direction, and the service of each service rate is mapped. In the mobile communication system having a TPR table including a reference TPR value determined in consideration of the type and number, etc., a TPR control apparatus for transmitting different packet data in the reverse direction, A base station for performing backward scheduling using the reference TPR value according to the type of packet data received from the mobile terminal, and then transmitting the TPR control information determined according to the scheduling result to the mobile terminal through a TPR control channel; Decide whether to increase or decrease the TPR according to the TPR control information received from the base station, and the reference TPR of the next packet data by increasing or decreasing the reference TPR value corresponding to the transmission rate of the packet data previously transmitted in the TPR table according to the determined increase or decrease Determine a transmission rate corresponding to the TPR value closest to the determined reference TPR value among the TPR values for the next type of packet data to be transmitted, and configure the transmission packet data at the determined transmission rate to perform power according to the TPR value. TPR control apparatus comprising a mobile terminal for transmitting to. Different packet data can be transmitted in the reverse direction, and a traffic to pilot rate (TPR) value for transmission of different packet data is mapped to each transmission rate that can be set in the reverse direction, and the type of service is performed for each transmission rate. In the mobile communication system having a TPR table having a reference TPR value determined in consideration of the number and the like, in the TPR control method for transmitting different packet data in the reverse direction, When the base station receives the packet data from the mobile station, the base station performs reverse scheduling using a reference TPR value of the TPR table according to the type of the received packet data, and then uses the TPR control channel determined according to the scheduling result. Transmitting to the mobile terminal through; Decide whether to increase or decrease the TPR according to the TPR control information received from the base station, and the reference TPR of the next packet data by increasing or decreasing the reference TPR value corresponding to the transmission rate of the packet data previously transmitted in the TPR table according to the determined increase or decrease Determine a transmission rate corresponding to the TPR value closest to the determined reference TPR value among the TPR values for the next type of packet data to be transmitted, and configure the transmission packet data at the determined transmission rate to perform power according to the TPR value. TPR control method comprising the step of transmitting to.

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