KR20080074673A - Method and apparatus for determining revers power of a mobile station in an orthogonal frequency division multiple system - Google Patents

Abstract

A method and an apparatus for determining the reverse transmission power of a mobile station in an OFDM(Orthogonal Frequency Division Multiplexing) system is provided to reduce the size of an RLPC(Reverse-Link Power Control) field without deteriorating granularity of a power level in comparison with a conventional technology. A method for determining the reverse transmission power of a mobile station in an OFDM system includes the steps of: receiving an F-SCCH(Forward-link Shared Control Channel) whose RLAM(Reverse-Link Assignment Message) is transmitted to a base station by a mobile terminal(401); reading PF field when the mobile terminal successfully demodulates the F-SCCH(405); nominally determining a data reverse transmission power level in contradiction to according to a DataCtolnormal,pf value corresponding to the field value(407); reading an RLPC field value(409); and determining a final DataCtoIassigned by applying a DataCtklOffset value indicated by the field value(411).

Description

METHOD AND APPARATUS FOR DETERMINING REVERS POWER OF A MOBILE STATION IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLE SYSTEM}

1 is a flowchart illustrating a method of determining reverse transmission power of a mobile terminal in a general OFDM system;

2 is a block diagram showing a configuration of a transmitting apparatus in an OFDM system to which the present invention is applied;

3 is a block diagram showing a configuration of a receiving apparatus in an OFDM system according to an embodiment of the present invention;

4 is a flowchart illustrating a method of determining a reverse transmit power level of a mobile terminal in an OFDM system according to an embodiment of the present invention.

The present invention relates to a method and apparatus for determining a transmission power of a mobile terminal in a mobile communication system, and more particularly, to a method and apparatus for determining an initial transmission power of a mobile terminal in an orthogonal frequency division multiplexing (OFDM) system. It is about.

Recently, the mobile communication system has been actively studied for the OFDM scheme as a method useful for high-speed data transmission in a wired or wireless channel. The OFDM method is a method of transmitting data using a multi-carrier, and a plurality of sub-carriers having mutual orthogonality to each other by converting symbol strings serially input in parallel. ), That is, a type of Multi-Carrier Modulation (MCM) that modulates and transmits a plurality of sub-carrier channels.

The OFDM scheme is, for example, Digital Audio Broadcasting (DAB), Digital Video Broadcasting (DVB), Wireless Local Area Network (WLAN), and Wireless Asynchronous Transfer Mode (Wireless Asynchronous Transfer Mode). : Widely applied to digital transmission technology such as WATM). In particular, the OFDM scheme uses a frequency spectrum superimposed so that the use of frequency is efficient, and is strong in frequency selective fading and multipath fading, and inter-symbol interference using a guard interval. Interference, hereinafter referred to as " ISI ", can be reduced, and it is possible to simply design an equalizer structure in hardware. In addition, the OFDM scheme has an advantage of being resistant to impulsive noise and thus can be actively used in a communication system.

Meanwhile, in the OFDM mobile communication system (hereinafter referred to as “OFDM system”), a forward-link shared control channel (hereinafter referred to as “F-SCCH”) is used for forward and reverse resource allocation and management, and data packet. As a control channel for transmitting a message related to the format definition of a mobile station, an access attempt approval of a mobile station, and the like, in order to actually transmit data in an OFDM system, control information should be transmitted through the F-SCCH. The longest control channel message sent on the SCCH is, for example, 25 bits long.

Among a plurality of control channel messages transmitted through the F-SCCH, a Reverse-link Assignment Message (RLAM) is a message for allocating or releasing resources to be used by a mobile terminal in a reverse link. Packet format (hereinafter referred to as "PF"), pilot pattern, and reverse-link power control, which define the characteristics of the (e.g., whether it is a fixed allocation resource), modulation and coding scheme. RLPC ").

Table 1 below shows some of the fields constituting the RLAM in a typical mobile communication system.

In Table 1, when the block type is 001, RLAM is indicated. In the remaining fields, the field value “0” represents the deactivation of the corresponding field and “1” represents the activation of the corresponding field. The total number of bits required for transmitting the RLAM at the base station is 25 bits.

라 칭하기로 한다. 상기

는 하기 <수학식 1>에서와 같이 이동 단말의 전송 PSD 증분값(

)를 결정하는데 적용된다.In Table 1, the RLPC field is used to determine the initial transmission power spectral density (hereinafter referred to as "PSD") to be used when the mobile station transmits data using the uplink resource allocated from the base station. As carrier-to-interference PSD information for the provided data, carrier-to-interference PSD information for the data is hereinafter referred to.

It will be called. remind

Is the transmission PSD increment value of the mobile terminal as shown in Equation 1 below.

Is applied to determine

는 기지국이 주변 셀들로부터 받는 열잡음 대비 간섭 PSD(Interference over Thermal PSD)를 의미하고,

는 파일럿에 대한 열잡음 대비 캐리어 PSD(Carrier over Thermal PSD)를 의미하며, 이러한 PSD 값들은 별도의 제어 채널을 통해서 전송될 수 있다.In Equation 1

Means the interference over thermal PSD received from the neighboring cells by the base station,

Denotes a carrier over thermal PSD for the pilot, and these PSD values may be transmitted through a separate control channel.

의 범위를 예컨대, -5dB에서 25dB라고 가정하고, 상기

의 범위를 1dB 크기로 나누면 총 31개의 전력 레벨들이 생성되므로 이 전력 레벨들을 나타내기 위해서는 5비트가 필요하게 된다. 예를 들어, 상기 전력 레벨들을 나타내기 위해 “00001”에서 “11111”까지 31개의 5비트 정보를 이용한다고 할 때, 이동 단말이 기지국으로부터 “00001”을 수신하게 되면, -5dB를 요구되는 수신 로 판단하게 되고, “01101”에 대해서는 8dB를 사용하게 된다. 따라서 이동 단말은 RLPC 필드에 있는 5비트의 정보를 읽고서는 어느 레벨의 송신 PSD로 데이터를 전송할지를 결정한다. Given the many possible PFs,

Assume that the range of is, for example, -5 dB to 25 dB,

Dividing the range by 1dB produces a total of 31 power levels, requiring 5 bits to represent these power levels. For example, suppose that 31 5-bit information is used from “00001” to “11111” to indicate the power levels. If the mobile terminal receives “00001” from the base station, it is required to receive -5 dB. In case of “01101”, 8dB is used. Therefore, the mobile terminal reads the 5-bit information in the RLPC field and determines which level of transmission PSD to transmit the data.

FIG. 1 is a flowchart illustrating a method of determining reverse transmission power of a mobile terminal in a general OFDM system. This is a flowchart illustrating an operation of a mobile terminal for determining transmission power of data using an RLPC field of RLAM.

값에 따라 초기 전송 전력의 레벨을 결정한다.In step 101 of FIG. 1, if the mobile station receives the F-SCCH from which the RLAM is transmitted from the base station, and the mobile station successfully demodulates the F-SCCH in step 101, the mobile station proceeds to step 105 and the mobile station proceeds to RLPC in RLAM. Read 5-bit information into the field value of the field. In step 107, the mobile terminal corresponds to the RLPC field value.

The initial transmit power level is determined according to the value.

In the above-described prior art, the mobile terminal reads the RLPC field inserted into the RLAM to determine the transmission power to be used, and only the RLPC field is considered in determining the transmission power level. Depending on the number, the required amount of information in the RLPC field is increased. Therefore, according to the prior art, there is a problem that the RLPC field may have a size larger than necessary in the RLAM.

The present invention for solving the above problems provides a method and apparatus that can reduce the amount of information of the control information transmitted to the mobile terminal for transmission power control of the mobile terminal in the OFDM system.

The present invention also provides a method and apparatus for reducing the amount of information required in the RLPC field in a reverse assignment message (RLAM) transmitted to the mobile terminal for transmission power control of the mobile terminal in an OFDM system.

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 be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

) 값을 확인하는 과정; 상기 역방향 전력 제어(RLPC) 필드로부터 PSD 옵셋(

) 값을 확인하는 과정; 상기 확인된

값을 이용하여 기본적인 역방향 전송 전력 레벨을 결정하는 과정; 및 상기 확인된

을 이용하여 최종 전송 전력 레벨을 결정하는 과정을 포함한다.According to an aspect of the present invention, a method for determining backward transmission power of a mobile terminal in an orthogonal frequency division multiplexing system includes a packet format (PF) field and a reverse power control (RLPC) field from a base station. Receiving the reverse assignment message; Carrier to interference PSD for corresponding data from the information in the Packet Format (PF) field (

) Checking the value; PSD offset from the reverse power control (RLPC) field

) Checking the value; Identified above

Determining a basic reverse transmit power level using the value; And identified above

Determining the final transmit power level by using.

) 값과 상기 역방향 전력 제어(RLPC) 필드로부터 PSD 옵셋(

) 값을 확인하고, 상기

값을 이용하여 기본적인 역방향 전송 전력 레벨을 결정하며 상기

을 이용하여 최종 전송 전력 레벨을 결정하는 전력 레벨 조정부를 포함한다.In addition, in an orthogonal frequency division multiplexing system according to an embodiment of the present invention, a mobile station includes: a receiving module for receiving a reverse assignment message including a packet format (PF) field and a reverse power control (RLPC) field from a base station; And a carrier-to-interference PSD for corresponding data from the information in the packet format (PF) field.

) And a PSD offset from the reverse power control (RLPC) field.

) Check the value, and

Value is used to determine the basic reverse transmit power level.

It includes a power level adjusting unit for determining the final transmission power level using.

In addition, a mobile terminal of an orthogonal frequency division multiple access system according to an embodiment of the present invention comprises: a receiving module for receiving a reverse assignment message including a packet format (PF) field and an RLPC field from a base station; And a power level adjusting unit for determining a corresponding value from the information of the packet format field and reflecting a PSD offset value to the determined value to determine reverse transmission power.

First, the basic concept of the present invention will be described. In general, when a mobile terminal transmits data, the level of transmission power may be correlated with a packet format to be used. That is, as the higher order modulation scheme is used, a higher power level must be used to obtain a desired signal-to-noise ratio (SNR), and the lower order modulation scheme can use a relatively low level of power. Therefore, if the correlation between the packet format PF for determining the modulation and coding scheme and the transmission power is used, it is possible to use one-to-one corresponding power level for the PF.

Therefore, if it is possible to determine the initial transmission power level in the data transmission of the mobile terminal based on the PF, the number of bits required for the RLPC field, without considering only the RLPC field to determine the power level of the mobile terminal as in the prior art Can be reduced.

To this end, the present invention proposes a method of using the RLPC field of the RLAM transmitted through the F-SCCH to determine the initial transmission power level of the mobile terminal, but using the PF field of the RLAM to reduce the required number of bits of the RLPC. . The present invention can efficiently support a hybrid automatic repeat request (HARQ) operation of the base station.

”)의 일 예를 나타낸 것이다.Referring to the present invention in detail, the following Table 2 shows the carrier-to-interference PSD information for the data corresponding to each PF (hereinafter, “

”) Is an example.

를 확인할 수 있으며, 확인된

에 따라 이동 단말은 데이터의 초기 전송 전력 레벨을 결정할 수 있다. 상기 <표 2>와 같이 변조 방식과 부호율의 쌍으로 이뤄진 16가지의 PF를 정의하고 있다면, PF에 대응하는

의 개수도 16가지가 된다. The mobile terminal can store the information of Table 2 in advance or know through signaling with the base station. Therefore, when the mobile terminal reads the PF field of RLAM, it corresponds to the PF.

You can check

The mobile terminal can determine the initial transmit power level of the data. If you define 16 PFs consisting of a modulation scheme and a code rate pair as shown in Table 2 above,

There are also 16 types.

의 맵핑 테이블(이하, “PF 맵핑 테이블”)은 이동 단말의 메모리에 저장되어 있다는 것을 가정하기로 한다. 따라서 상기 PF 맵핑 테이블을 이용하면, 다른 정보를 필요로 하지 않고 PF만으로 이동 단말의 초기 전송 전력 레벨을 기본적으로 결정할 수 있다. 즉, 이동 단말로부터 전송된 데이터를 기지국이 성공적으로 복조하기 위해서는 기지국은 이동 단말에게 이동 단말의 전송 데이터에 대한 PF를 알려주게 되는데, 본 발명에 따라 이동 단말은 RLAM의 여러 필드 중 PF 필드를 통해서 자신이 사용해야 할 데이터의 패킷 포맷뿐만 아니라, PF와

의 맵핑 테이블에 따라 데이터의 초기 전송 전력 레벨도 결정할 수 있다.In this embodiment, the PF and

It is assumed that the mapping table (hereinafter, referred to as "PF mapping table") is stored in the memory of the mobile terminal. Therefore, using the PF mapping table, it is possible to basically determine the initial transmit power level of the mobile terminal using only PF without requiring other information. That is, in order for the base station to successfully demodulate the data transmitted from the mobile terminal, the base station informs the mobile terminal of the PF for the transmission data of the mobile terminal. According to the present invention, the mobile terminal transmits the PF field through the PF field. In addition to the packet format of the data

The initial transmit power level of the data may also be determined according to the mapping table.

Hereinafter, a method for efficiently supporting HARQ when performing reverse transmission power control of a mobile terminal using PF according to the present invention will be described below.

First, HARQ is one of important technologies used to increase the reliability and data throughput of data transmission in a packet-based mobile communication system. HARQ, as is well known, refers to a technology in which ARQ (Automatic Repeat Request) technology and FEC (Forward Error Correction) are combined. ARQ is a widely used technology in wired and wireless data communication systems. When using ARQ technology, a transceiver assigns a serial number to a data packet transmitted according to a predetermined method, and the data receiver uses the serial number. Reliable data transmission can be performed by requesting the transmitter to retransmit the missing number in the received packet.

The FEC overcomes errors occurring in an environment such as noise or fading generated during data transmission and reception by adding redundant bits to data transmitted according to a predetermined rule, such as convolutional coding or turbo coding. To demodulate the original transmitted data. In a mobile communication system using HARQ combining the ARQ and the FEC, the receiver performs a cyclic redundancy check (CRC) check on the decoded data through a predetermined FEC inverse process on the received data to determine whether there is an error in the received data. If there is no error, the transmitter transmits the next data packet by feeding back an acknowledgment (ACK) to the transmitter. If the CRC check determines that there is an error in the received data, the receiver feeds back a non-acknowledgement (NACK) to the transmitter so that the transmitter retransmits the previously transmitted packet.

If the maximum number of transmissions supported by HARQ is 6, the base station retransmits the same packet for five times except for the initial transmission packet. In this case, the base station sets a target HARQ transmission number. The target HARQ number of 3 means that when the base station transmits a total of three times for the packet, the successful packet demodulation of the mobile station is 99 within three times. The goal is to make it possible. The HARQ performed in the reverse direction also performs the same operation so that the base station feeds back the ACK / NACK to the packet transmitted by the mobile station. If the target HARQ transmission count is 3, the base station transmits the packet within three transmission times performed by the mobile station. The data transmission power of the mobile terminal must be adjusted to successfully demodulate the data. As such, when the base station operates in a mobile communication system to which the HARQ technique is applied, the base station needs to change the target HARQ without fixing the number of target HARQs.

Since the allowable delay is different depending on whether the type of traffic to be transmitted by the mobile terminal is voice or burst data such as BE (Best Effort), when the short delay is required, the number of target HARQs is set small. If a relatively large delay can be tolerated, it means that the number of target HARQs is set large. To this end, in the present invention, the basic transmission power of the mobile terminal is first determined through the PF information transmitted through the RLAM, and then the transmission power level of the determined data is similarly determined using the RLPC information transmitted through the RLAM. By precisely adjusting, the data transmission power of the mobile terminal can be finally determined.

값)으로 RLAM의 RLPC 필드가 표현해야 하는 가지 수가 많이 요구되지 않는다. 따라서 RLPC 필드의 크기를 예컨대, 4 비트라고 가정하면, 총 16개의 PSD 옵셋 값을 지원할 수 있다. That is, in the present invention, the existing RLPC field included in the RLAM is used to further adjust the transmission power level of the mobile terminal, and the PF is basically used to determine the initial transmission power level to be allocated to the data. Therefore, in the present invention, since the basic transmit power level is determined using PF, an offset value for adjusting the additional power level of the mobile terminal (

Value) does not require as many branches as the RLPC field in RLAM should represent. Therefore, assuming that the size of the RLPC field is, for example, 4 bits, a total of 16 PSD offset values can be supported.

값을 정하고, 이를 이용하여 이동 단말의 데이터 전송 전력 레벨을 기본적으로 결정하도록 한 뒤, 추가적으로 전송 전력 레벨 조정을 위해서 RLPC 필드에 정의된

값을 이용하여 최종 전송 전력 레벨을 결정하면, RLAM

에서 RLPC 필드에 요구되는 비트 수를 줄일 수 있다. Accordingly, the mobile terminal reads the PF field of the RLAM received from the base station using the PF mapping table stored in the memory.

Determine the data transmission power level of the mobile terminal by using this value, and then define the RLPC field for additional transmission power level adjustment.

Value is used to determine the final transmit power level.

Can reduce the number of bits required for the RLPC field.

As described above, in the mobile communication system to which the present invention is applied, the data transmission power level of the mobile terminal is determined using two methods as follows.

<Transmission Power Level Determination Method>

에 따라 기본적인(nominal) 전송전력 레벨을 미리 정의함.(예를 들어, PF 및

맵핑 테이블 이용)1) Corresponding by PF

Pre-define the nominal transmit power level according to (e.g. PF and

With mapping tables)

값을 이용하여 기본적인 전송 전력 레벨로부터 옵셋값 만큼 이동된 상대적인(relative) 최종 전송 전력 레벨을 결정함.2) predefined in the RLPC field to further adjust the nominal transmit power level;

Value to determine the relative final transmit power level shifted by the offset value from the basic transmit power level.

를 나타냈던 종래의 방식과 달리, PF 필드와 RLPC 필드를 모두 사용하는 본 발명에서는 결과적으로

결정을 위해 하기 <수학식 2>의 우변과 같이 두 개의 항으로 나누어 표현할 수 있다.Using only the RLPC field

In contrast to the conventional method, which is described above, in the present invention using both the PF field and the RLPC field, as a result,

For the determination, it can be expressed by dividing into two terms as shown on the right side of Equation 2 below.

2 is a block diagram showing the configuration of a transmitting apparatus in an OFDM system to which the present invention is applied.

In the transmitting apparatus of FIG. 2, it is assumed that the control channel F-SCCH and the data channel F-DCH are transmitted simultaneously. The F-SCCH including RLAM information includes an encoder 201 for encoding data of a control channel, an interleaver 203 for interleaving the encoded data, a modulator 205 for modulating the interleaved data, and an out-of-band. A boundary tone inserter 207 for inserting a guard tone to reduce interference of a signal, a pilot tone inserter 209 for inserting a pilot tone for channel estimation in a mobile terminal, and a quadrature phase, for example, QPSK. Shift keying) is passed through a transmission module including a QPSK spreader (211) for spreading the signal signal in which the pilot tone is inserted. The QPSK diffuser may apply various diffusion schemes known as examples.

According to the present invention, the required number of bits of the RLPC field included in the RLAM information has a smaller number of bits than that of the conventional RLPC field since the number of bits required to enable additional power control of the mobile terminal is required.

In addition, the transmission module multiplexes the symbols transmitted through the F-SCCH and the F-DCH, and then performs an IFFT (Inverse Fast Fourier Transform) process to convert the OFDM data into an IFFT processor 215, and in front of the OFDM data. CP inserter 217 for inserting a cyclic prefix (CP) to prevent signal interference, and an RF processor for up-converting the OFDM-inserted OFDM signal into an RF signal and transmitting the radio frequency through an antenna 221 to the wireless network ( 219, and an F-DCH transmitter 213 that performs encoding and modulation for transmitting the F-DCH.

Since the configuration of the F-DCH transmitter 213 is a known technique, a detailed description thereof will be omitted herein.

3 is a block diagram illustrating a configuration of a receiving apparatus in an OFDM system according to an embodiment of the present invention.

Referring to the configuration of the receiving apparatus of the present invention for receiving the F-SCCH including the RLAM in Figure 3, the receiving module for receiving the OFDM signal from the radio channel to restore to the original data OFDM received through the antenna 301 from the radio channel An RF processor 303 for frequency downconverting the signal into a baseband signal, a CP remover 305 for removing the contaminated CP from the OFDM signal due to propagation delay, multipath, and the like, and a time at which the CP is removed Fast Fourier Transform (FFT) processor 307 for converting an OFDM signal in a domain to a signal in a frequency domain, and a despreader for outputting the tones of each signal by despreading the OFDM signal in the frequency domain, for example. It includes.

The receiving module further includes a pilot tone extractor 309 for extracting pilot tones from the tones of each despread signal, a data tone extractor 313 for extracting data tones from the tones of each despread signal, and A channel estimator 311 for estimating a channel using the extracted pilot tones, a demodulator 315 for demodulating the data tones using the channel estimation result, and a deinterleaver for deinterleaving the demodulated data 317 and a decoder 319 for restoring the deinterleaved data to original data.

In the receiving apparatus of FIG. 3, a part related to the gist of the present invention is a configuration for receiving RLAM including PF and / or RLPC fields for transmission power control of a mobile terminal. Therefore, since the role of the PF in the general forward-link assignment message (FLAM) is irrelevant to the gist of the present invention, description of the F-DCH receiver related to the FLAM will be omitted.

값을 출력하는 PF 맵핑기(325)와, 상기 PF 맵핑기(325)로부터 전달된

값을 이용하여 기본적인 전 송 전력 레벨을 결정하며, 상기 RLPC 추출기(323)로부터 전달된 RLPC 필드의 PSD 옵셋값인

값을 이용하여 상기 기본적인 전송 전력 레벨로부터

값 만큼 이동된 상대적인(relative) 전송 전력 레벨을 추가적으로 결정하는 전력 레벨 결정기(327)를 포함한다.도 4는 본 발명의 실시 예에 따라 OFDM 시스템에서 이동 단말의 역방향 전송 전력 레벨을 결정하는 방법을 나타낸 순서도이다. In addition, the receiving device of FIG. 3 includes a power level adjusting unit C1 for determining a transmission power level of data to be transmitted by the mobile terminal according to the present invention. The power level adjusting unit C1 includes a PF extractor 321 for extracting the PF field of the RLAM received from the F-SCCH, an RLPC extractor 323 for extracting the RLPC field, and a PF field value extracted through the PF extractor. Corresponding

PF mapper 325 for outputting a value, and the PF mapper 325

Value is used to determine the basic transmission power level, which is a PSD offset value of the RLPC field transmitted from the RLPC extractor 323.

Value from the default transmit power level

And a power level determiner 327 that additionally determines a relative transmit power level shifted by a value. FIG. 4 illustrates a method of determining a reverse transmit power level of a mobile terminal in an OFDM system according to an embodiment of the present invention. The flowchart shown.

값을 메모리로부터 읽어 들여 그

값에 따라 파일럿 전력 대비 데이터 역방향 전송 전력 레벨을 기본적으로 결정한다. In step 401 of FIG. 4, when the mobile terminal receives the F-SCCH from which the RLAM is transmitted from the base station, and in step 401 the mobile terminal successfully demodulates the F-SCCH, the mobile terminal proceeds to step 405 in which the mobile terminal receives the received RLAM. Read the PF field first to determine the basic transmit power of the data. And in step 407, the value of the PF field.

Reads a value from memory

Based on the value, the data reverse transmission power level is determined based on the pilot power.

값을 읽는다. 411 단계에서 이동 단말은 상기 읽혀진

값을 먼 저 정해진

값에 적용하여 상기 407 단계에서 기본적으로 결정된 전송 전력 레벨에서 상기

값 만큼 양의 방향 또는 음의 방향으로 조정된 최종 전송 전력 레벨을 결정한다. Then, if additional transmission power adjustment is needed, the mobile station can perform a 4-bit RLPC field in step 409.

Read the value. In step 411 the mobile terminal is read

Set the value first

A value at the transmit power level basically determined in step 407 in response to the value.

Determines the final transmit power level adjusted in the positive or negative direction by a value.

값이 존재하므로, 15개의

값(0000에서 1110에 해당되는 값)들은 -7dB에서 +7dB까지의 범위를 1dB 간격으로 나누었을 때의 PSD 옵셋값으로, 1111은 단말기에게 현재의 전송 PSD인 증분값(

)를 그대로 사용하도록 하기 위해 쓰일 수 있다. 이 경우 PF에 대응하는

에 의해 결정된 데이터의 기본적인 전송 PSD가 5dB이라면, RLPC 필드의

값이 0010인 경우 -5dB를 의미하므로 최종 전송 전력 레벨은 0dB가 된다.For example, if the size of the RLPC field is 4 bits, 16

Since the value exists, 15

The values (values corresponding to 0000 to 1110) are PSD offset values obtained by dividing the range from -7 dB to +7 dB by 1 dB interval, and 1111 indicates an incremental value which is the current transmission PSD to the terminal.

) Can be used as is. In this case, corresponding to PF

If the basic transmission PSD of the data determined by 5 dB is 5 dB,

If the value is 0010, it means -5dB, so the final transmit power level is 0dB.

값에 따라 이동 단말의 데이터 기본적인 전송 전력의 레벨을 결정하고(normal 전력 레벨), 종래 보다 적은 비트 수로 전송되는 RLPC 필드의

값에 의해 기본적인 전력 레벨을 좀 더 세밀히 조정함으로써(relative 전력 레벨), 종래의 기술에 비해 전력 레벨의 granularity를 떨어뜨리지 않으면서도 RLPC 필드의 크기를 줄일 수 있다.As described above, according to the present invention, it is basically mapped to a PF field value.

Determine the level of data basic transmit power of the mobile terminal according to the value (normal power level), and determine the RLPC field transmitted with a smaller number of bits than before.

By further adjusting the basic power level by value (relative power level), the size of the RLPC field can be reduced without compromising the granularity of the power level compared to the prior art.

In addition, according to the present invention, the number of bits saved in the RLPC field can be used for other purposes, and the dynamic HARQ operation of the target HARQ number can be supported to enable efficient HARQ operation.

Claims (2)

A method for determining reverse transmission power of a mobile terminal in an orthogonal frequency division multiplexing system, Receiving a reverse assignment message including a packet format (PF) field and a reverse power control (RLPC) field from a base station; Carrier to interference PSD for corresponding data from the information in the Packet Format (PF) field (

) Checking the value; PSD offset from the reverse power control (RLPC) field

) Checking the value; Identified above

Determining a basic reverse transmit power level using the value; And Identified above

Determining a final transmit power level by using the backward transmit power determination method of the mobile terminal. A receiving module for receiving a reverse assignment message including a packet format (PF) field and a reverse power control (RLPC) field from a base station; And Carrier to interference PSD for corresponding data from the information in the Packet Format (PF) field (

) And a PSD offset from the reverse power control (RLPC) field.

) Check the value, and

Value is used to determine the basic reverse transmit power level.

The mobile terminal of the orthogonal frequency division multiple access system comprising a power level adjusting unit for determining the final transmission power level using the.

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