KR20010104824A - Apparatus for demodulating channel and method thereof in mobile telecommunication system - Google Patents

Abstract

The present invention relates to a mobile communication system, receiving a dedicated physical channel signal and a common pilot channel signal from a base station, despreading the received dedicated physical channel signal, and channel estimation of the received common pilot channel signal for each antenna, The despread dedicated physical channel signal may be channel compensated according to a transmission diversity encoding time interval with the common pilot channel signal obtained by the channel estimation.

Description

Apparatus and method for channel demodulation in mobile communication systems {APPARATUS FOR DEMODULATING CHANNEL AND METHOD THEREOF IN MOBILE TELECOMMUNICATION SYSTEM}

The present invention relates to a mobile communication system, and more particularly, to an apparatus and method for demodulating a channel using a transmission diversity scheme.

In a mobile telecommunication system, a phase of a received signal is distorted due to a fading phenomenon occurring on a wireless channel. If the phase of the received signal distorted by fading phenomenon is not compensated for during data demodulation, it becomes a cause of information error of the transmitted data transmitted from the transmitting side and causes the quality of the mobile communication service to deteriorate.

Downlink (Base Station) of the International Mobile Telecommunication-2000 (IMT-2000) mobile communication system currently being standardized by the 3rd Generation Partnership Project (3GPP) in order to estimate and compensate signal phase distortion on the wireless channel to minimize information error. In the direction of a mobile station, the transmit diversity scheme is applied. The transmit diversity scheme refers to an algorithm for receiving a downlink signal to obtain diversity gain, and is classified into an open loop mode and a closed loop mode. In the open loop mode, when a base station encodes a data signal and transmits the data signal through a diversity antenna, the mobile station receives and decodes a signal transmitted from the base station to obtain diversity gain. In the closed loop mode, (1) a mobile station estimates and calculates a channel environment that a signal transmitted through each transmit antenna of a base station will experience, and (2) the mobile station maximizes the power of a received signal with the calculated prediction value. When the weight of the base station antennas that can be generated is calculated and transmitted to the base station through uplink (uplink direction from the mobile station to the base station), (3) the base station receives the weight signal transmitted from the mobile station and The weight of the antennas is adjusted.

When the Space Time block coding based Transmit Diversity (STTD) scheme, which is one of the open loop modes, is applied, the STTD is a dedicated physical channel (DPCH). Physical CHannel), Primary_Common Control Physical CHannel (P_CCPCH), Secondary _Common Control Physical CHannel (S_CCPCH), Synchronization CHannel (SCH), Page Indication CHannel (PICH) In addition, AICH (Aquisition Indication CHannel) and PDSCH (Physical Downlink Shared CHannel) are taken into consideration, and a channel prediction value for STTD decoding is applied to each antenna using a common pilot channel (CPICH).

Here, a channel modulation apparatus of a mobile communication system to which the transmission diversity scheme is applied will be described in detail with reference to FIG. 1.

1 is a block diagram illustrating a base station channel modulation apparatus of a mobile communication system, wherein the channel modulation apparatus includes two common pilot channels and one dedicated physical channel having different pilot patterns for diversity antennas. Has Here, although the dedicated physical channel is described as an example, other channels in which STTD may be considered as described above are also possible. The channel encoder 111, the rate matcher 113, and the interleaver 115 of the dedicated physical channel operate in the same manner as when the transmit diversity scheme is not applied.

First, the channel encoder 111 encodes data to be transmitted through the dedicated physical channel, and transmits the encoded data to the rate matcher 113. The rate matcher 113 matches the encoded data output from the channel encoder 111 to a rate to be transmitted and outputs the data to the interleaver 115. The interleaver 115 inputs data output from the rate matcher 113, interleaves the data according to a pre-set interleaving scheme, and outputs the data to the MUX 117. The MUX 117 inputs and multiplexes the data output from the interleaver 115 and the TPC and TFIC data to the STTD encoder 119. The STTD encoder 119 inputs a mixed signal of the interleaved data, TPC, and TFIC data output from the multiplexer 117 to STTD-encodes the output signal to the MUX 121. Here, the STTD encoder 119 encodes the interleaved data, TPC, and TFIC data by the STTD method to generate symbols to be transmitted through the first antenna and symbols to be transmitted through the second antenna, respectively, to the MUX 121. Output The MUX 121 outputs an STTD encoded first antenna symbol and a pilot symbol, and an STTD encoded second antenna symbol and a diversity pilot symbol output from the STTD encoder 119. The STTD-encoded first antenna symbol and the pilot symbol (PILOT symbol) multiplexed are respectively multiplexed to the mixer 123, and the STTD-encoded second antenna symbol and the diversity pilot symbol (Diversity PILOT symbol) are multiplexed. The symbol is output to the mixer 125. The mixer 123 is a channel code (CHANNELIZATION CODE) having a symbol multiplexed with a STTD encoded first antenna symbol and a pilot symbol output from the MUX 121 and a spreading length M, and long scrambling. LONG SCRAMBLING CODE C _P is mixed and output to the adder 131. The adder 131 is a mixing code of the channel length CHANNELIZATION CODE and LONG SCRAMBLING CODE C _{P ′} and CPICH mixed with the SPREADING LENGTH 256 output from the mixer 127 and the mixer 123. Add the symbols output from the C) to the first antenna to transmit to the mobile station.

On the other hand, the mixer 123 is a channel code having a symbol multiplexed with the STTD encoded second antenna symbol and the diversity pilot symbol output from the MUX 121 and a spreading length M (CHANNELIZATION). CODE) and LONG SCRAMBLING CODE C _P are mixed and output to the adder 133. The adder 133 is a symbol mixed with a channel code (CHANNELIZATION CODE) and a long scrambling code C _{P ′} having a spreading length 256 output from the mixer 129 and a diversity CPICH and the mixer. The symbol output at 125 is added to be output to the second antenna for transmission to the mobile station.

Here, an embodiment of channel encoding encoded by the STTD encoder 119 will be described with reference to FIG. 2.

FIG. 2 is a diagram illustrating an embodiment of channel encoding through an STTD encoder, in which symbols are sequentially STTD encoded by the STTD encoder 119 according to a transmit diversity encoding interval used in a transmit diversity scheme. For example, if the input to the transmission diversity coding period T ₁ symbols S _1, a transmission diversity coding period T ₂ the symbol S ₂ is the STTD encoder 119 sequentially to the STTD encoder 119 is S in which the input ₁ by the symbol STTD encoding S ₂ through the second antenna to the S ₁ S ₂ through a first antenna and outputs as -S ₂ ^* S ₁ ^*.

Here, channel bit encoding of the STTD encoding described with reference to FIG. 2 will be described with reference to FIG. 3. As described in the STTD encoding, when the symbols S ₁ and S ₂ input according to the transmission diversity encoding time interval are generated as channel bits of b ₀ b ₁ and b ₂ b ₃ , respectively, the STTD encoder 119. ), The channel bits of symbols S ₁ , S ₂ , that is, b ₀ b ₁ b ₂ b ₃ , are input. The STTD encoder 119 is the b ₀ b ₁ b ₂ b ₃ to the channel bit STTD encoding, the channel bits of a first antenna _{b 0 b 1 b 2 b 3} (S 1 S 2), to the second antenna Outputs channel bits -b ₂ b ₃ b ₀ -b ₁ (-S ₂ ^* S ₁ ^* ).

The structure of the common pilot channel described with reference to FIG. 1 will be described with reference to FIG. 4. 4 is a diagram illustrating a structure of a common pilot channel, wherein the common pilot channel is a physical reference used as a phase reference of downlink physical channels (eg, dedicated physical channels) in a direction of a mobile station from a base station; Channel. The common pilot channel is divided into a first antenna common pilot channel and a second antenna common pilot channel, and when the downlink transmission diversity scheme is applied, the first antenna common pilot channel and the second antenna common pilot channel. The common pilot symbol transmitted through the channel is spread with the same spreading code and the scrambling code and then transmitted to the first antenna and the second antenna, respectively. Here, the first antenna common pilot channel and the second antenna common pilot channel use different pilot symbol patterns. In the first antenna pilot pattern, A (= 1 + j) is transmitted during all time periods, while in the second antenna pattern, A, -A, -A, A and the like are repeated, and the first slot of the frame is the first slot. The last two symbol intervals of 15 slots consist of A and -A. Since the base station transmits a common pilot channel through each of the first antenna and the second antenna by using different pilot symbol patterns, the mobile station uses the different pilot patterns and the common pilot symbols received through the first antenna. The common pilot symbol received through the second antenna is distinguished.

As described above with reference to FIGS. 1 to 4, in a channel modulation apparatus of a base station of a mobile communication system, a transmission diversity scheme is applied to modulate physical channels having different pilot phases through a plurality of antennas, for example, two antennas. Sending. Therefore, the mobile station of the mobile communication system needs a synchronous channel demodulation system that independently measures the phase distortion on the propagation path for each transmitting antenna and compensates the received signal for each channel transmitted by applying the transmit diversity from the base station. It became.

Accordingly, an object of the present invention is to provide a synchronous channel demodulation device in a mobile communication system employing a transmission diversity scheme.

Another object of the present invention is to provide a synchronous channel demodulation method in a mobile communication system employing a transmit diversity scheme.

The apparatus of the present invention for achieving the above object; A channel demodulation device for a mobile communication system, comprising: a despreader for despreading a dedicated physical channel signal received through a dedicated physical channel, a channel estimator for channel estimation of a common pilot channel signal received through a common pilot channel for each antenna; And a channel compensator for channel compensating the despread dedicated physical channel signal and the channel estimated common pilot channel signal according to a transmission diversity encoding time period.

The method of the present invention for achieving the above object; A channel demodulation method of a mobile communication system, the method comprising: despreading a dedicated physical channel signal received through a dedicated physical channel, estimating a common pilot channel signal received through a common pilot channel for each antenna, and And performing channel compensation on the spread dedicated physical channel signal and the channel estimation common pilot channel signal according to the transmission diversity encoding time interval.

1 is a block diagram showing a base station channel modulation apparatus of a mobile communication system

2 illustrates an embodiment of channel encoding via an STTD encoder.

3 illustrates one embodiment of channel bit encoding via an STTD encoder.

4 illustrates a structure of a common pilot channel.

5 is a block diagram showing a mobile station channel demodulation device according to an embodiment of the present invention;

6 is a block diagram illustrating in detail the channel estimator of FIG.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that in the following description, only parts necessary for understanding the operation according to the present invention will be described, and descriptions of other parts will be omitted so as not to disturb the gist of the present invention.

5 is a block diagram showing a mobile station channel demodulation device according to an embodiment of the present invention.

In the base station of the mobile telecommunication system, a transmit diversity scheme (for example, space time block coding based transmit diversity (STTD) is referred to as a "STTD"). The data symbol to be applied is transmitted through a plurality of antennas (for example, the first antenna and the second antenna) in downlink (downlink direction from the base station to the mobile station), and then the mobile station transmits the signal transmitted from the base station. Received through one antenna, the data symbol transmitted through each of the plurality of antennas in the base station is received to the mobile station through the independent radio path for each antenna, the received data symbol (Rx_IN) is a dedicated physical Dedicated physical channel despreader 511. The dedicated physical channel despreader 511 is used for channel classification. Perform complex-type despreading on the received data symbol with a channel code (CHANNELIZATION CODE), which is a spread code, and a scrambling code of the corresponding cell, and despread a dedicated physical channel signal to complex-dump and dump. The complex sum & dumper 513 performs the integration / dump on the despread dedicated physical channel signal output from the dedicated physical channel despreader 511 to perform the dedicated / dump. The symbol energy of the physical channel is output to a conjugator 525 and a mixer 529. The dedicated physical channel despreader 511 is a symbol of a dedicated physical channel that modulates the received dedicated physical channel signal at the base station. The despreading unit is determined according to a time period, and the complex & dump unit 513 is despread in the symbol time period unit of the dedicated physical channel in the dedicated physical channel despreader 511. Integration / Dump is performed on the physical channel signal.

Meanwhile, the data symbol Rx_IN received through the independent propagation path for each antenna is input to the common pilot channel (CPICH) despreader 517. The common pilot channel despreader 517 inputs the received data symbol and uses a common pilot channel classification spread code (eg, an orthogonal variable spread factor (OVSF) code) for detecting a reference phase of a common pilot channel and a corresponding cell. The complex type despreading is performed using the scrambling code and output to the complex sum & dumper 519. The complex & dump unit 519 obtains common pilot channel symbol energy by inputting a despreaded common pilot channel signal output from the common pilot channel despreader 517 to perform integration / dump. The output signals of the complex sum & dumper 513 and the complex sum & dumper 519 identify which of the signals transmitted through the first antenna and the second antenna by the base station, respectively. This is an impossible condition, and the signal's amplitude and phase are distorted through multipath fading, and noise is also mixed.

The complex & dump unit 519 is configured to convert the despreaded common pilot channel symbol energy output from the common pilot channel despreader 517 into a first antenna channel estimator 521 and a second antenna channel estimator 523. ) Each of the first antenna channel estimator 521 and the second antenna channel estimator 523 outputs a channel estimate for each independent propagation path of each of the first antenna and the second antenna. Here, the channel estimate for the first antenna channel output from the first antenna channel estimator 521 is h ₁ , and the channel estimate for the second antenna channel output from the second antenna channel estimator 523 is h ₂ . define. H ₁ output from the first antenna channel estimator 521 is input to a conjugator 527, h ₂ output from the second antenna channel estimator 523 is input to the mixer 531, and h is output. ₁ and h ₂ are noise canceled and are also phase distortion measurement states occurring on the transmission paths of the first and second antennas, respectively.

On the other hand, the dedicated physical channel symbol energy corresponding to the transmission diversity coding interval output by the complex & dumper 513 (for example, the reception only physical channel symbol energy corresponding to the first transmission diversity coding interval is r ₁ . And a reception only physical channel symbol energy corresponding to a second transmission diversity encoding interval is defined as r ₂ ). The output signal is output to the conjugator 525 and the mixer 529.

Here, the dedicated physical channel reception signals r ₁ and r ₂ will be described.

First, a dedicated physical channel signal modulated by the base station by using the transmission diversity scheme using the STTD scheme is received by the mobile station through independent propagation paths for each of the first and second antennas of the base station. The received dedicated physical channel signal is a signal passed through a dedicated physical channel despreader 511 and a complex & dumper 513, that is, the first and second received dedicated physical channel symbol energy according to a transmission diversity coding interval are represented by the following equation. It can be represented by 1 and (2), respectively.

Here, h ₁ is a channel characteristic experienced by a signal transmitted through the base station first antenna, h ₂ is a channel characteristic experienced by a signal transmitted through the base station second antenna, and h ₁ and h ₂ are two characteristics. Assume that there is little change during the symbol period. S ₁ is a first symbol of a block to be encoded by the STTD method, S ₂ is a second symbol of a block to be encoded by the STTD method, and n ₁ and n ₂ are white additive Gaussian noise added to the received signal. Additive White Gaussian Noise).

R ₁ output by the complex & dumper 513 is input to the conjugator 525 during the first transmission diversity time period, and the conjugator 525 is output from the complex & dumper 513. Enter r ₁ to take the conjugate and output it to the mixer 531. The mixer 531 mixes a signal output from the condenser 525 and a signal output from the second antenna channel estimator 523, that is, h ₂ , and outputs the mixed signal to the first switch 537. Since the signal output from the mixer 531 is a received signal r ₁ , that is, a signal for the first symbol, the switch 537 switches to the delay unit 539. The delay unit 539 delays the output signal of the mixer 531 switched by the first switch 537 to the multiplier 541 by delaying two time slots. The multiplier 541 inputs the signal output from the delayer 539, multiplies -1, and outputs the signal to the second switch 543. The second switch 543 switches to output the signal output from the multiplier 541 to the adder 535.

The r ₂ outputted by the complex & dumper 513 is input to the conjugator 525 during the second transmission diversity time period, and the conjugator 525 is outputted by the complex & dumper 513. Input r ₂ to take a conjugate and output it to the mixer 531. The mixer 531 mixes a signal output from the condenser 525 and a signal output from the second antenna channel estimator 523, that is, h ₂ , and outputs the mixed signal to the first switch 537. Since the signal output from the mixer 531 is a received signal r ₂ , that is, a signal for the second symbol, the switch 537 switches to the second switch 543. The second switch 543 switches to output the signal output from the first switch 537 to the adder 535.

On the other hand, the mixer 529 conjugator r ₁ output from the complex & dump unit 513 and a signal output from the first antenna channel estimator 521, that is, h ₁ , in the first transmission diversity time period. Through the mixed signal 527, the conjugated signal is mixed and output to the delay unit 533. In the second transmission diversity time period, the mixer 529 may output the signal r ₂ output from the complex & dump unit 513 and the signal output from the first antenna channel estimator 521, that is, h ₁ . The mixed signal obtained by the conjugate is mixed and output to the delay unit 533. The delay unit 533 inputs the signal output from the mixer 529, delays one time slot, and outputs the delayed signal to the adder 535. The adder 535 inputs and adds the signals output from the delay unit 533 and the second switch 543, and outputs the added signal FNG_OUT.

Here, the output of the adder 535 with respect to the first received signal r ₁ can be expressed by Equation 3 below.

Similarly, the output of the adder 535 for the received signal r ₂ according to the second transmit diversity interval can be expressed by Equation 4 below.

That is, S ₁ ′ and S ₂ ′ output from the adder 535 are signals with a distorted amplitude and phase compensated for, and the continuous signal is input to a channel decoding circuit to perform error correction.

A process of channel estimation of the signal output from the complex & dump unit 519 by the first antenna channel estimator 521 and the second antenna channel estimator 523 will be described with reference to FIG. 6.

FIG. 6 is a detailed block diagram illustrating the channel estimator of FIG. 5. The complex & dump unit is used to measure phase distortion through channel estimation for independent propagation paths of a first antenna and a second antenna. The channel estimation for the propagation paths of the first antenna and the second antenna is performed by the first antenna channel estimator 521 and the second antenna channel estimator 523 using the output signal of the Sum & Dumper 519 as an input signal. Perform. Each of the first antenna channel estimator 521 and the second antenna channel estimator 523 has the same configuration, but since the common pilot channel for channel estimation is applied differently, only the operation of the first antenna estimator 521 is performed. Let's explain.

It is assumed that the output signal of the complex & dumper 519, that is, the input signal of the first antenna estimator 521 is x (n), and x (n) is the first and second antennas of the base station. Common pilot channel symbol energy transmitted through the. The input signal x (n) is a mixed signal in which a pilot symbol pattern is not identified for each of the first antenna and the second antenna. First, the common pilot channel modulation pattern complex conjugator (Complex Conjugate of CPICH Modulation Pattern) 611 is a symbol obtained by taking a complex conjugate of the common pilot channel symbol pattern to identify the pilot symbol energy for each antenna propagation path. Is generated and output to the mixer 613. The mixer 613 mixes and complexes the input signal x (n) and a symbol obtained by taking a complex conjugate of a common pilot channel symbol pattern output from the common pilot channel modulation pattern complex condenser 611. Output to dumper & The complex & dump unit 615 performs a complex addition between symbols in which orthogonality is established between the pilot symbols of the first antenna and the second antenna and outputs the output signal of the common pilot channel symbol rate output from the mixer 613. The result is output to a low pass filter (LPF) 617. In this case, the complex addition operation principle performs an operation between two signals, but a signal used for one operation is not used for operation with the next signal. That is, in order to identify the channel estimation between the first antenna and the second antenna, as described in FIG. 4, it means performing an operation between symbols in which orthogonality is established between the pilot symbols of the first antenna and the second antenna. Although the signal output from the complex-and-dump 615 has a channel estimation for the propagation paths of the first and second antennas independently, the signal having the noise component is mixed in the channel estimated signal. to be. The signal output from the complex & dumper 615 is input to the low pass filter (LPF) 617, and the low pass filter 617 is a one-tap infinite impulse response (IIR). ) Filters the signal output from the complex & dump 615 with a filter to remove the noise and output.

Herein, the input signal x (n) through the IIR filter is A ₁ and b ₀ are coefficients given according to the characteristics of the IIR filter, and the bandwidth of the signal to be filtered can be adjusted by adjusting the a ₁ and b ₀ . Do. The final output signal y (n) passed through the lowpass filter 617 is a noise canceled channel estimate value and is a phase distortion measurement signal generated on the transmission paths of the first and second antennas of the base station. h1 and h2 are shown.

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 the base station of the mobile communication system transmits a signal using a transmission diversity scheme, the mobile station receives the transmitted diversity transmitted signal and compensates for phase distortion and amplitude according to a reception path. Has the advantage of enabling.

Accordingly, there is an advantage in that channel demodulation with channel compensation that compensates for the phase distortion and amplitude is possible.

Claims (22)

In the channel demodulation device of a mobile communication system, A despreader for despreading a dedicated physical channel signal received through the dedicated physical channel; A channel estimator for channel estimation of the common pilot channel signal received through the common pilot channel for each antenna; And a channel compensator for channel compensating the despread dedicated physical channel signal and the channel estimated common pilot channel signal according to a transmission diversity encoding time interval. The method of claim 1, The channel estimator; A common pilot channel despreader for despreading a signal received through the common pilot channel by mixing with a spreading code; A common pilot channel modulation pattern complex conjugate for generating a complex conjugate value of the common pilot channel modulation pattern; A mixer for mixing a complex conjugate value of the despread common pilot channel signal and the common pilot channel modulation pattern; And a complex and a dumper for integrating and dumping the output signal of the mixer. The method of claim 2, And the channel estimator further comprises a lowpass filter for removing noise included in the complex and dump output signals. The method of claim 3, And the low pass filter is an infinite impulse response filter that converts a filter characteristic coefficient to adjust a bandwidth of a signal to be filtered. The method of claim 2, The channel estimator is configured to equal the number of antennas to which the transmit diversity scheme is applied. The method of claim 2, And wherein the common pilot channel modulation pattern has a different pattern for each antenna. The method of claim 1, The transmit diversity is a channel demodulation device, characterized in that for applying space-time block coding transmit diversity. The method of claim 1, The channel compensator; A first conjugator for conjugating the channel estimated signal; A first mixer for mixing the conjugator output signal and the despread dedicated physical channel signal; A second conjugate that takes the conjugate of the despread dedicated physical channel signal, A second mixer for mixing the channel estimated signal and the second condenser output; A switching unit which determines a path for adding a signal output from the second mixer to a signal output from the first mixer; And an adder for adding the second mixer output signal and the first mixer output signal. The method of claim 8, And the channel compensator further comprises a first delay unit connected between the first mixer and the adder to delay the output of the first mixer by one time slot. The method of claim 8 The switching unit and the first switch is connected to the second mixer; A second delay unit connected to the second switch to delay the two time slots when the second mixer output is an odd number symbol; A multiplier for multiplying -1 by the second delay output; And a second switch having one end connected to the multiplier and another end connected to the adder. The method of claim 10, And the switching unit directly switches the first switch and the second switch when the output of the second mixer is an even number symbol. The method of claim 5, The channel compensation signal of the channel compensator is a channel demodulation device, characterized in that the channel compensation signal received through the first antenna when the antenna is composed of a first antenna, the second antenna is calculated by the following equation (5). However, h ₁ : channel characteristics experienced by the signal transmitted to the first antenna h ₂ : Channel characteristic experienced by the signal transmitted to the second antenna S ₁ : First symbol of a block to be coded using a space-time time block transmission diversity scheme S ₂ : Second symbol of a block to be coded using a space-time time block transmission diversity scheme n ₁ : White additive Gaussian noise added to the signal received by the first antenna n ₂ : White additive Gaussian noise added to the signal received by the second antenna The method of claim 12, And a channel compensation signal received through the second antenna by the channel compensator is calculated through Equation 6 below. In the channel demodulation method of a mobile communication system, Despreading a dedicated physical channel signal received through the dedicated physical channel; Channel estimation of the common pilot channel signal received through the common pilot channel for each antenna; And channel compensating the despread dedicated physical channel signal and the channel estimated common pilot channel signal according to a transmission diversity encoding time interval. The method of claim 14, The channel estimation process; Despreading a common pilot channel signal by mixing a spreading code with the received common pilot channel signal; Generating a complex conjugate value of a common pilot channel modulation pattern; Mixing a complex conjugate value of the despread common pilot channel signal and the common pilot channel modulation pattern; And integrating and dumping a signal obtained by mixing the despread common pilot channel signal and a complex conjugate value of the common pilot channel modulation pattern. The method of claim 12, And performing low pass filtering on the integrated and dumped signals to remove noise included in the integrated and dumped signals. The method of claim 15, The channel demodulating method performs channel estimation for each antenna applied in the transmit diversity. The method of claim 15, Wherein the common pilot channel modulation pattern has a different pattern for each transmit antenna. The method of claim 14, The transmit diversity is a channel demodulation method characterized by applying a space-time block coded transmit diversity scheme. The method of claim 14, Compensating the channel; Mixing a conjugate value of the channel estimated signal and the despread dedicated physical channel signal; Mixing a conjugate value of the despread dedicated physical channel signal and the channel estimated signal; The despread only dedicated signal obtained by mixing the conjugate value of the channel estimated signal and the despread dedicated physical channel, and the signal obtained by mixing the conjugate value of the despread dedicated physical channel and the channel estimated signal And demodulating and adding the path according to the symbol order of the physical channel signal. The method of claim 20, The channel compensated signal is a channel demodulation method, characterized in that when the antenna is composed of a first antenna, a second antenna, the channel compensation signal received through the first antenna is calculated by the following equation (7). However, h ₁ : channel characteristics experienced by the signal transmitted to the first antenna h ₂ : Channel characteristic experienced by the signal transmitted to the second antenna S ₁ : First symbol of a block to be coded by a space-time time block transmission diversity scheme S ₂ : Second symbol of a block to be coded using a space-time time block transmission diversity scheme n ₁ : White additive Gaussian noise added to the signal received by the first antenna n ₂ : White additive Gaussian noise added to the signal received by the second antenna The method of claim 21, And a channel compensation signal received through the second antenna is calculated by Equation (8).