WO2005048498A2

WO2005048498A2 - Transmission power control method in a wireless communication system

Info

Publication number: WO2005048498A2
Application number: PCT/KR2004/002936
Authority: WO
Inventors: Chan Ho Kyung; Jong Hoe An; Young Woo Yun; Suk Hyon Yoon; Ki Jun Kim; Soon Yil Kwon
Original assignee: Lg Electronics Inc.
Priority date: 2003-11-13
Filing date: 2004-11-12
Publication date: 2005-05-26
Also published as: CN1914824A; BRPI0416336A; CA2546389C; WO2005048498A3; KR20070012323A; KR101084149B1; CN1914824B; CA2546389A1

Abstract

A transmission power control method in a wireless communication system comprises the steps of receiving from a base station via an overhead message a first gain value (S23) associated with controlling transmission power for transmitting data acknowledge information (ACK, NAK) and a second gain value (S13) associated with controlling transmission power for transmitting channel quality information (CQI) wherein the transmission power of the reverse-acknowledgment channel (R-ACKCH) and the reverse-channel quality indicator channel (R-CQICH) are independently determined (S24, S14) using said first and second gain values.

Description

TRANSMISSION POWER CONTROL APPARATUS IN WIRELESS COMMUNICATION SYSTEM AND METHOD THEREFOR

Field of the Invention

The present invention relates to a power control method applicable to mobile

communication systems, and more particularly, to a transmission power control apparatus

and method using reverse channel quality indicator and acknowledgment indicator.

Background Art In radio communications, channel environment varies according to the drift of mobile

terminal's location. Hence, it is preferable that the modulation and coding scheme are

modified to fit the channel quality for each situation.

With regard to setting a modulation scheme, when the channel quality is good (i.e., less

interference), the communication system is able to use modulation enabling high-speed

data transfer, such as QAM (quadrature amplitude modulation) and M-ary PSK (phase

shift keying). However, in case that channel quality is poor, it is able to use such

modulation as BPSK (binary phase shift key) resistant against interference.

With regard to setting a coding scheme, when the channel quality is good, less

redundancy (thus, a high coding rate) is possible, so that data can be transmitted with

higher data rate. However, when the channel environment is poor, the channel coding is

performed with more redundancy (lower coding rate), so that data can be transmitted with

a lower data rate. In order to vary the modulation and coding scheme appropriately according to the

variation of the channel quality, information about the current channel quality is needed. A

forward channel quality is measured by a mobile terminal and is transmitted to a base

station via a reverse channel quality indicator channel (R-CQICH). It should be noted that

the term reverse channel is denoted as communication originating from a mobile terminal

and transmitted to a network, such as a base station.

H-ARQ (hybrid automatic repeat request) is a method for improving reliability and

throughput in a manner of combining ARQ (automatic repeat request) and FEC (forward

error correction). ARQ is a method for improving transmission reliability in a manner of

requesting retransmission of the same information until receiving errorless information if

error exists in the transmitted information. And, FEC is a method for improving reliability in

a manner of correcting errors having occurred during transmission.

During good channel quality, the frequency of errors in the received information is low.

Hence, a retransmission is requested using ARQ, whereby reliability of the received

information can be maintained. However, during poor channel quality, the frequency of

errors in the received information is high. If ARQ is used without FEC, it may cause the

increase of the number of retransmissions. Hence, the throughput of the system will be

decreased since ARQ does not have any error-correction function.

Since such a problem can be solved by FEC, the H-ARQ system using both ARQ and

FEC has been proposed. As one sort of H-ARQ, there is the IR (incremental redundancy)

system. In the IR system, a transmitting side initially transmits data encoded with high

coding rate which have small number of redundant bits. If the receiving side receives data with errors, it requests retransmission. In response to the request, the transmitting side

transmits additional redundant bits, which are caused by low rate encoding.

A receiving side combines to decode the already received data and the redundant bits.

In doing so, the retransmitted bits are to compensate the previously sent packet. In the HARQ system of a wireless communication system, a mobile terminal decodes a

received packet to check a presence or non-presence of errors and should feed back an

ACK (acknowledgment) or NAK (negative acknowledgment) signal to a base station

according to a result of the check. A base station having received the NAK signal

retransmits the packet. By combining to decode the retransmitted packet and the initially

transmitted packet, the mobile terminal has a diversity or coding gain. The ACK NAK

signal transmitted from the mobile terminal to the base station is transmitted to the base

station via a reverse acknowledgment channel (R-ACKCH).

In a typical wireless communication system, nominal attribute gain for R-ACKCH is set

to -3dB. During the course of implementation, it has been determined that this gain was

set too low for a proper ACK operation. In other words, current nominal attribute gain for

R-ACKCH makes false alarm probability (probability that the base station receiver detects

ACK even when the transmitter does not transmit anything on R-ACKCH) too high

resulting in a large number of RLP retransmissions.

To identify the problem, simulations were performed with current nominal adjustment

gain value for R-ACKCH under AWGN channel. The simulations were performed with

9600bps R-FCH on top of R-ACKCH. The pilot level was power controlled so that 1% FER

could be achieved for R-FCH. In FIG. 1 , the line 2 represents the CDF of demodulator output when ACK signal is

transmitted. The line 4 is the complementary CDF of demodulator output when the

transmitter does not transmit anything. The line 6 is the complementary CDF of

demodulator output when NAK signal is transmitted. For ease of explanation, the following probabilities can be defined.

P_A-N : Probability that the ACK signal is falsely detected as NAK.

P_N-A: Probability that the NAK signal is falsely detected as ACK.

P_No-A : Probability that the receiver detects ACK signal even when the mobile station

doesn't transmit anything on R-ACKCH. In this example, it is assumed that one threshold is given to the output of base station

demodulator so that the base station detects ACK or NAK. It should be noted that 'no

signal' does not need to be differentiated from 'NAK' since the base station behavior might

be the same for these two cases. The criteria used for determining the threshold level is to

maintain the P_A-N and P_N-A below certain level. The choice of this level should be

implementation dependent. However, P_A-N of 0.01 seems to be reasonable choice. From

FIG. 1 , P_N-A is 0.001 for this threshold, which seems quite reasonable. However, it turns

out that P_No-A is 0.3, which is a bit high for proper operation. The high P_NO-_A may lead to

some erroneous event.

The erroneous event due to this false alarm on R-ACKCH can be explained as follows.

When a mobile terminal completely misses the forward packet data control channel given

to it, the mobile terminal will not transmit any signal on the R-ACKCH. For about 30% of

these situations, the base station falsely decides that ACK signal was transmitted from the mobile terminal and is going to proceed with new packet for that ARQ channel, resulting in

RLP layer retransmission for that packet. Therefore, it is suggested that the channel gain

(i.e., transmission power) for R-ACKCH needs to be modified to resolve this problem. Transmission power of R-CQICH is determined using a R-CQICH power adjustment

gain and a R-ACKCQICH gain to a pilot power (RLGAIN_ACKCQICH_PILOT). The R-

CQICH power adjustment gain is individually transmitted to each mobile terminal from a

base station. And, the R-ACKCQICH gain to a pilot power is commonly transmitted to the

all mobile terminals from the base station.

Similarly, transmission power of R-ACKCH is determined using a R-ACKCH power

adjustment gain and a R-ACKCQICH gain to a pilot power (RLGAIN_ACKCQICH_PILOT).

The R-ACKCH power adjustment gain is individually transmitted to each mobile terminal

from a base station. And, the R-ACKCQICH gain to a pilot power is commonly transmitted

to all the mobile terminals from the base station.

As mentioned in the foregoing description, in determining each of the R-CQICH and R-

ACKCH transmission powers, the R-ACKCQICH gain to a pilot power

(RLGAIN_ACKCQICH_PILOT) is commonly used. However, because the common factor

(RLGAIN_ACKCQICH_PILOT) is used in determining both the R-CQICH and the R-

ACKCH transmission powers, the following problems are inevitable.

For all mobile terminals in a cell, it may occur that the transmission power of R-ACKCH

needs to be increased but the transmission power of R-CQICH need to be maintained. In

such a case, the R-ACKCH power adjustment gain should be transmitted to all mobile

terminals in the cell individually. This is because the transmission power of R-CQICH is increased as well as that of R-

ACKCH, if the R-ACKCQICH gain to a pilot power (RLGAIN_ACKCQICH_PILOT) is

transmitted to all mobile terminals in a cell using an overhead message.

For instance, in detecting ACK/NAK, the base station performs a threshold detection

using the receiving power of R-ACKCH. Hence, in case that the transmission power of R-

ACKCH is too small, the base station may incorrectly detect No-signal as NAK. If the R-

ACKCQICH gain to a pilot power (RLGAIN_ACKCQICH_PILOT) is transmitted to all

mobile terminals to solve the problem, the transmission power of R-CQICH is

unnecessarily increased to be inefficient. Meanwhile, if the base station transmits the R-

ACKCH power adjustment gain to each of the mobile terminals, a message load

transmitted to the mobile terminal increases and the corresponding transmission process

gets very complicated.

Disclosure of Invention Accordingly, the present invention is directed to a transmission power control method

of R-CQICH (reverse-channel quality indicator channel) and R-ACKCH (reverse-

acknowledgment channel) that substantially obviates one or more problems due to

limitations and disadvantages of the related art.

An object of the present invention is to provide an apparatus and method for controlling

transmission powers of R-CQICH (reverse-channel quality indicator channel) and R-

ACKCH (reverse-acknowledgment channel) independently.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary

skill in the art upon examination of the following or may be learned from practice of the

invention. The objectives and other advantages of the invention may be realized and

attained by the structure particularly pointed out in the written description and claims

hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with the purpose of

the invention, as embodied and broadly described herein, a method of controlling

transmission power in a mobile communication system comprises receiving a packet data

from a network and determining whether the packet data is received correctly, receiving a

first gain value (for example, RLGAIN_ACKCH_PILOT) and a second gain value (for

example, RLGAlN_CQICH_PILOT) from the network, wherein the first gain value is

associated with controlling transmission power for transmitting data acknowledge

information (ACK), and the second gain value is associated with controlling transmission

power for transmitting channel quality information independent from the first gain value,

and the first and second gain values are capable of being received by a plurality of mobile

terminals associated with the network; and determining an acknowledgement channel

power by using at least a nominal reverse acknowledgment channel attribute gain and the

first gain value.

According to one aspect of the present invention, the method further comprises

determining a channel quality indicator channel power by using at least a nominal reverse

channel quality indicator channel attribute gain and the second gain value.

According to another aspect of the present invention, at least one of the first gain value and the second gain value is received through an overhead message from the network,

the overhead message capable of being received by mobile terminals in at least one cell

controlled by the network. Preferably, the overhead message comprises at least

one of ESPM (Extended System Parameters Message) and MCRRPM (MC-RR

Parameters Message). The first and the second gain values are transmitted using at

least one of UHDM (Universal Handoff Direction Message) and ECAM (Extended Channel

Assignment Message).

According to another aspect of the present invention, the acknowledgment channel

power is determined by: acknowledgment channel power = mean pilot channel output power + Y

* (Nominal_Reverse_Acknowledgement_Channel_Attribute_Gain + Reverse_ Channel_Adjustment_Gain for the acknowledgment channel - Multiple_Channel_Adjustment_Gain for the acknowledgment channel + first gain value), wherein the mean pilot channel output power is a mean power value

of a reverse pilot channel, the Y is a constant, the

Nominal_Reverse_Acknowledgement_Channel_Attribute_Gain is a gain value previously

known to the network and the mobile terminal, the Reverse_Channel_Adjustment_Gain[R-

ACKCH] is a gain value that the network informs each mobile terminal via message, the

Multiple_Channel_Adjustment_Gain is a gain value used when at least two code channels

are assigned to the mobile terminal as well as the reverse pilot channel, wherein the value

of Y is preferably 0.125.

According to one aspect of the present invention, the method further comprises determining a channel quality indicator channel power by using at least a nominal reverse

channel quality indicator channel attribute gain and the second gain value.

According to another aspect of the present invention, the channel quality indicator

channel power is determined by: channel quality indicator channel power = mean pilot channel output power + Y

* (Nominal_Reverse_Channel_Quality_Indicator_Channel_Attribute_Gain + Reverse_Channel_Quality_lndicator_Channel_Attribute_Adjustment_Gain + Reverse_Channel_Adjustment_Gain for a channel quality indicator channel - Multiple_Channel_Adjustment_Gain for the channel quality indicator channel + second gain value), wherein the mean pilot channel output power is a mean power

value of a reverse pilot channel, the Y is a constant, the

Nominal_Reverse_Channel_Quality_Indicator_Channel_Attribute_Gain is a gain value

previously known to the network and the mobile terminal, the

Reverse_Channel_Quality_Indicator_Channel_Attribute_Adjustment_Gain is a gain value

that the network informs each mobile terminal via message, the

Reverse_Channel_Adjustment_Gain is a gain value that the network informs each terminal

via message, the Multiple_Channel_Adjustment_Gain is a gain value used when at least

two code channels are assigned to the mobile terminal as well as the reverse pilot channel.

The value of Y is preferably 0.125. A mobile terminal for controlling transmission power in a mobile communication system

comprises means for receiving a packet data from a network and determining whether the

packet data is received correctly; means for receiving a first gain value and a second gain value from the network, wherein the first gain value is associated with controlling

transmission power for transmitting data acknowledge information, and the second gain

value is associated with controlling transmission power for transmitting channel quality

information independent from the first gain value, and the first and second gain values are

capable of being received by a plurality of mobile terminals associated with the network;

and means for determining an acknowledgement channel power by using at least a

nominal reverse acknowledgment channel attribute gain and the first gain value.

According to another embodiment of the present invention, a method of controlling

transmission power comprises transmitting a packet data to a mobile terminal; transmitting

a first gain value and a second gain value to the mobile terminal, wherein the first gain

value is associated with controlling transmission power for transmitting data acknowledge

information, and the second gain value is associated with controlling transmission power

for transmitting channel quality information independent from the first gain value, and the

first and second gain values are capable of being received by a plurality of mobile

terminals associated with the network; and receiving the data acknowledgment information

from the mobile terminal through an acknowledgment channel transmitted at

acknowledgement channel power determined by the mobile terminal using at least a

nominal reverse acknowledgment channel attribute gain and the first gain value. According to one aspect of the present invention, the network further comprises

receiving a channel quality indicator through a channel quality indicator channel

transmitted by the mobile terminal with channel quality indicator channel power determined

by using at least a nominal reverse channel quality indicator channel attribute gain and the second gain value.

Therefore, the present invention enables to efficiently control the transmission powers

of the R-CQICH and R-ACKCH. Also, the present invention reduces overhead messages

being transmitted from the base station to the mobile terminal.

It is to be understood that both the foregoing general description and the following

detailed description of the present invention are exemplary and explanatory and are

intended to provide further explanation of the invention as claimed.

Brief Description of The Drawings The accompanying drawings, which are included to provide a further understanding of

the invention and are incorporated in and constitute a part of this application, illustrate

embodiment(s) of the invention and together with the description serve to explain the

principle of the invention. In the drawings:

FIG. 1 is simulation results with R-ACKCH nominal attribute gain of -3dB. FIG. 2 is a flowchart of a transmission power control method of R-CQICH.

FIG. 3 is a flowchart of a transmission power control method of R-ACKCH. FIG. 4 is an exemplary diagram of an overhead message format including

RLGAIN_CQICH_PILOT and RLGAIN_ACKCH_PILOT values.

FIG. 5 illustrates a mobile communication device according to one embodiment of the

present invention.

Best Mode for Carrying Out The Invention Reference will now be made in detail to the preferred embodiments of the present

invention, examples of which are illustrated in the accompanying drawings. Wherever

possible, the same reference numbers will be used throughout the drawings to refer to the

same or like parts. Although the present invention is illustrated with respect to a mobile

terminal, it is contemplated that the present invention may be utilized anytime it is desired

to provide new transport configurations for establishing a connection between a mobile

communication device and a network (also referred to as a base station).

FIG. 2 is a flowchart of a transmission power control method for R-CQICH. Referring

to FIG. 2, a mobile terminal receives a signal transmitted from a base station (S11) and

then estimates a current forward channel quality (S12). And, the mobile terminal computes

an R-CQICH transmission power using a CQICH power gain to a reverse pilot power value

RLGAIN_CQICH_PILOT received from the base station (S13, S14). It should be noted

that the steps of estimating the current forward channel quality (S12) and receiving

RLGAIN_CQICH_PILOT from the base station (S13) may be interchanged. Preferably, the transmission power of R-CQICH is computed using Equation 1.

[Equation 1] P_RCQ_ICH = mean pilot channel output power + 0.125 ^*(Nominal_Reverse_Channel_Quality_Indicator_Channel_Attribute_Gain + Reverse_Channel_Quality_lndicator_Channel_Attribute_Adjustment_Gain + Reverse_Channel_Adjustment_Gain[R-CQICH] - Multiple_Channel_Adjustment_Gain[R-CQICH]+ RLGAIN_CQICH_PILOT)

In Equation 1 , the mean pilot channel output power is a mean power value of a reverse

pilot channel, Nominal_Reverse_Channel_Quality_lndicator_Channel_Attribute_Gain is a gain value previously known to a base station and a mobile terminal,

Reverse_Channel_Quality_lndicator_Channel_Attribute_Adjustment_Gain[R-CQICH] is a

gain value that the base station informs each mobile terminal via message if necessary,

Reverse_Channel_Adjustment_Gain[R-CQICH] is a gain value that the base station

informs each mobile terminal via message if necessary,

Multiple_Channei_Adjustment_Gain[R-CQICH] is a gain value used when at least two

code channels are assigned to the mobile terminal as well as the reverse pilot channel,

and RLGAIN_CQICH_PILOT is a gain value of R-CQICH power to a reverse pilot channel

power that the base station informs the all mobile terminals in a cell via an overhead

message.

FIG. 3 is a flowchart of a transmission power control method for R-ACKCH. Referring

to FIG. 3, data are preferably transmitted at high data rate between the base station and

the mobile terminal in a following manner.

A base station transmits a packet to a mobile terminal. And, the mobile terminal having

received the packet (S21) performs decoding thereon (S22).

If the decoding is successful (S22) (i.e., there is no error in the decoded data), the

mobile terminal transmits an acknowledgment (ACK) signal to the base station to inform

the successful decoding. The base station having received the ACK signal transmits a next

packet. If the decoding fails (S22), the mobile terminal transmits a non-acknowledgement

(NAK) signal to the base station to inform the decoding failure (S25). The base station

having received the NAK signal retransmits the packet. The ACK NAK signal is transmitted via a R-ACKCH. The transmission power of R-

ACKCH is computed using the ACKCH power gain to a reverse pilot power value

(RLGAIN_ACKCH_PILOT) received from the base station (S23, S24). And, the ACK/NAK

signal is transmitted to the base station with the computed transmission power (S25). Preferably, the transmission power of R-ACKCH is computed using Equation 2.

[Equation 2] P_ACKCH = mean pilot channel output power + 0.125 * (Nominal_Reverse_Acknowledgement_Channel_Attribute_Gain + Reverse_ Channel_Adjustment_Gain[R-ACKCH]

- MultipIe_Channel_Adjustment_Gain [R-ACKCH] + RLGAIN_ACKCH_PILOT) In Equation 2, the mean pilot channel output power is a mean power value of a reverse

pilot channel, Nominal_Reverse_Acknowledgement_Channel_Attribute_Gain is a gain

value previously known to a base station and mobile terminal,

Reverse_Channel_Adjustment_Gain[R-ACKCH] is a gain value that the base station

informs each mobile terminal via message if necessary,

Multiple_Channel_Adjustment_Gain[R-ACKCH] is a gain value used when at least two

and RLGAIN_ACKCH_PILOT as a gain value of R-ACKCH power to a reverse pilot

channel power that the base station informs the all mobile terminals in a cell via an

overhead message. FIG. 4 is an exemplary diagram of an overhead message format including

RLGAIN_CQICH_PILOT and RLGAIN_ACKCH_PILOT values. Such message is

transmitted from a base station to a mobile station residing in a cell controlled by such base station.

Referring to FIG. 4, RLGAIN_CQICH_PILOT and RLGAIN_ACKCH_PILOT values for

computing the transmission powers of R-CQICH and R-ACKCH, respectively, can be

transmitted using one or more fields of ESPM (Extended System Parameters Message),

MCRRPM (MC-RR Parameters Message), UHDM (Universal Handoff Direction Message),

and ECAM (Extended Channel Assignment Message). The ESPM and MCRRPM are

common channel messages which are provided to a plurality of mobile terminals in a cell.

On the other hand, UHDM and ECAM are dedicated messages which are provided to a

specific mobile terminal in a cell. Accordingly, the present invention efficiently controls the transmission powers of each

of the R-CQICH and R-ACKCH. And, the present invention reduces the amount of data

being transmitted from the base station to the mobile terminal.

Referring to FIG. 5, a block diagram of a mobile communication device 400 of the

present invention is illustrated, for example a mobile phone for performing the methods of

the present invention. The mobile communication device 400 includes a processing unit

410 such as a microprocessor or digital signal processor, an RF module 435, a power

management module 405, an antenna 440, a battery 455, a display 415, a keypad 420, a

storage unit 430 such as flash memory, ROM or SRAM, a speaker 445, a microphone 450,

and, optionally, a SIM card 425. A user enters instructional information, such as a telephone number, for example, by

pushing the buttons of the keypad 420 or by voice activation using the microphone 450.

The processing unit 410 receives and processes the instructional information to perform the appropriate function, such as to dial the telephone number. Operational data may be

retrieved from the storage unit 430 to perform the function. Furthermore, the processing

unit 410 may display the instructional and operational information on the display 415 for

the user's reference and convenience. The processing unit 410 issues instructional information to the RF section 435, to

initiate communication, for example, by transmitting radio signals comprising voice

communication data. The RF module 435 includes a receiver and a transmitter to receive

and transmit radio signals. The antenna 440 facilitates the transmission and reception of

radio signals. Upon receiving radio signals, the RF module 435 may forward and convert

the signals to baseband frequency for processing by the processing unit 410. The

processed signals may be transformed into audible or readable information output, for

example, via the speaker 445.

It will be apparent to one skilled in the art that the steps described in FIGS. 2 - 4 may

be readily implemented using, for example, the processing unit 410 or other data or digital

processing device, either alone or in combination with external support logic.

Although the present invention is described in the context of mobile communication, the

present invention may also be used in any wireless communication systems using mobile

devices, such as PDAs and laptop computers equipped with wireless communication

capabilities. Moreover, the use of certain terms to describe the present invention should

not limit the scope of the present invention to certain type of wireless communication

system, such as CDMA. The present invention is also applicable to other wireless

communication systems using different air interfaces and/or physical layers, for example, TDMA, FDMA, WCDMA, UMTS, etc.

The preferred embodiments may be implemented as a method, apparatus or article of

manufacture using standard programming and/or engineering techniques to produce

software, firmware, hardware, or any combination thereof. The term "article of

manufacture" as used herein refers to code or logic implemented in hardware logic (e.g.,

an integrated circuit chip, Field Programmable Gate Array (FPGA), Application Specific _*

Integrated Circuit (ASIC), etc.) or a computer readable medium (e.g., magnetic storage

medium (e.g., hard disk drives, floppy disks, tape, etc.), optical storage (CD-ROMs, optical

disks, etc.), volatile and non-volatile memory devices (e.g., EEPROMs, ROMs, PROMs,

RAMs, DRAMs, SRAMs, firmware, programmable logic, etc.).

Code in the computer readable medium is accessed and executed by a processor.

The code in which preferred embodiments are implemented may further be accessible

through a transmission media or from a file server over a network. In such cases, the

article of manufacture in which the code is implemented may comprise a transmission

media, such as a network transmission line, wireless transmission media, signals

propagating through space, radio waves, infrared signals, etc. Of course, those skilled in

the art will recognize that many modifications may be made to this configuration without

departing from the scope of the present invention, and that the article of manufacture may

comprise any information bearing medium known in the art. The logic implementation shown in the figures described specific operations as

occurring in a particular order. In alternative implementations, certain of the logic

operations may be performed in a different order, modified or removed and still implement preferred embodiments of the present invention. Moreover, steps may be added to the

above described logic and still conform to implementations of the invention.

It will be apparent to those skilled in the art that various modifications and variations

can be made in the present invention. Thus, it is intended that the present invention covers

the modifications and variations of this invention provided they come within the scope of

the appended claims and their equivalents.

Claims

What is claimed is:

1. A method of controlling transmission power in a mobile communication system, the method comprising: 5 receiving a packet data from a network and determining whether the packet data is received correctly; receiving a first gain value and a second gain value from the network, wherein the first gain value is associated with controlling transmission power for transmitting data acknowledge information, and the second gain value is associated with controlling

l o transmission power for transmitting channel quality information independent from the first gain value, and the first and second gain values are capable of being received by a plurality of mobile terminals associated with the network; and determining an acknowledgement channel power by using at least a nominal reverse acknowledgment channel attribute gain and the first gain value.

15

2. The method of claim 1 , further comprising: determining a channel quality indicator channel power by using at least a nominal reverse channel quality indicator channel attribute gain and the second gain value.

3. The method of claim 1 , wherein at least one of the first gain value and the

second gain value is received through an overhead message from the network, the

overhead message capable of being received by mobile terminals in at least one cell

controlled by the network.

4. The method of claim 3, wherein the overhead message comprises at least

one of ESPM (Extended System Parameters Message) and MCRRPM (MC-RR

Parameters Message).

5. The method of claim 1 , wherein the first and the second gain values are

transmitted using at least one of UHDM (Universal Handoff Direction Message) and ECAM

(Extended Channel Assignment Message).

6. The method of claim 1 , wherein the acknowledgment channel power is

determined by: acknowledgment channel power = mean pilot channel output power + Y * (Nominal_Reverse_Acknowledgement_Channel_Attribute_Gain + Reverse_ Channel_Adjustment_Gain for an acknowledgment channel - Multiple_Channel_Adjustment_Gain for the acknowledgment channel + first gain value), wherein the mean pilot channel output power is a mean power value

of a reverse pilot channel, the Y is a constant, the

known to the network and the mobile terminal, the Reverse_Channel_Adjustment_Gain is

a gain value that the network informs each mobile terminal via message, the

are assigned to the mobile terminal as well as the reverse pilot channel.

7. The method of claim 6, wherein Y is 0.125.

8. The method of claim 2, wherein the channel quality indicator channel

power is determined by: channel quality indicator channel power = mean pilot channel output power + Y * (Nominal_Reverse_Channel_Quality_lndicator_Channel_Attribute_Gain + Reverse_Channel_Quality_lndicator_Channel_Attribute_Adjustment_Gain

+ Reverse_Channel_Adjustment_Gain for a channel quality indicator channel - Multiple_Channel_Adjustment_Gain for the channel quality indicator channel + second gain value), wherein the mean pilot channel output power is a mean power

value of a reverse pilot channel, the Y is a constant, the Nominal_Reverse_Channel_Quality_lndicator_Channel_Attribute_Gain is a gain value

previously known to the network and the mobile terminal, the

Reverse_Channel_Quality_lndicator_Channel_Attribute_Adjustment_Gain is a gain value

that the network informs each mobile terminal via message, the

9. The method of claim 8, wherein Y is 0.125.

10. A method of controlling transmission power in a mobile communication

system, the method comprising: transmitting a packet data to a mobile terminal; transmitting a first gain value and a second gain value to the mobile terminal,

wherein the first gain value is associated with controlling transmission power for

transmitting data acknowledge information, and the second gain value is associated with

controlling transmission power for transmitting channel quality information independent

from the first gain value, and the first and second gain values are capable of being

received by a plurality of mobile terminals associated with the network; and receiving the data acknowledgment information from the mobile terminal through

an acknowledgment channel transmitted at acknowledgement channel power determined

by the mobile terminal using at least a nominal reverse acknowledgment channel attribute

gain and the first gain value.

11. The method of claim 10, further comprising: receiving a channel quality indicator through a channel quality indicator channel

by using at least a nominal reverse channel quality indicator channel attribute gain and the

second gain value.

12. The method of claim 10, wherein at least one of the first gain value and

the second gain value is transmitted through an overhead message, the overhead

message capable of being received by mobile terminals in at least one cell controlled by

the network.

13. The method of claim 12, wherein the overhead message comprises at

least one of ESPM (Extended System Parameters Message) and MCRRPM (MC-RR

Parameters Message).

14. The method of claim 10, wherein the first and the second gain values are

(Extended Channel Assignment Message).

15. The method of claim 10, wherein the acknowledgment channel power is

determined by: acknowledgment channel power = mean pilot channel output power + Y ^* (Nominal_Reverse_Acknowledgement_Channel_Attribute_Gain + Reverse_ Channel_Adjustment_Gain for an acknowledgment channel

- Multiple_Channel_Adjustment_Gain for the acknowledgment channel + first gain value), wherein the mean pilot channel output power is a mean power

value of a reverse pilot channel, the Y is a constant, the

Multiple_Channel_Adjustment__Gain is a gain value used when at least two code channels

are assigned to the mobile terminal as well as the reverse pilot channel.

16. The method of claim 15, wherein Y is 0.125.

17. The method of claim 11 , wherein the channel quality indicator channel

power is determined by: channel quality indicator channel power = mean pilot channel output power + Y

* (Nominal_Reverse_Channel_Quality_lndicator_Channel_Attribute_Gain + Reverse_Channel_Quality_Indicator_Channel_Attribute_Adjustment_Gain + Reverse_Channel_Adjustment_Gain for a channel quality indicator channel - Multiple_Channel_Adjustment_Gain for the channel quality indicator channel + second gain value), wherein the mean pilot channel output power is a mean

power value of a reverse pilot channel, the Y is a constant, the

Nominal_Reverse_Channel_Quality_lndicator_Channel_Attribute_Gain is a gain value

previously known to the network and the mobile terminal, the

that the network informs each mobile terminal via message, the

8. The method of claim 17, wherein Y is 0.125.