WO2011065609A1

WO2011065609A1 - Data transmission and receiving device and method in wireless communication system

Info

Publication number: WO2011065609A1
Application number: PCT/KR2009/007078
Authority: WO
Inventors: 황인관
Original assignee: 충북대학교 산학협력단
Priority date: 2009-11-30
Filing date: 2009-11-30
Publication date: 2011-06-03

Abstract

The present invention relates to a data transmission and receiving device and method under a high Doppler frequency fading environment in a wireless communication system that supports an orthogonal frequency division multiple access mode. Thus, the present invention implements a device and a method for transmitting or receiving data by applying a PAPR reduction method and a differential space time coding method in a downlink. Further, a second embodiment of the present invention implements a device and a method for transmitting or receiving data by applying a PAPR reduction method and a space time block coding method in an uplink in order to increase the channel capacity.

Description

【Specification】

[Name of invention]

Data transmission / reception device and method in wireless communication system

Technical Field

The present invention relates to a data transmission and reception apparatus and method in a wireless communication system, and more particularly, to a high speed data transmission and reception apparatus and method in a high doppler frequency fading environment in a wireless communication system supporting an orthogonal frequency division multiple access scheme. will be.

BACKGROUND ART Mobile communication technology is based on code division multiple access (CDMA) technology based on frequency division multiple access (0FDMA), which facilitates high-speed data transmission and is robust against multipath delay through three generations of voice and low speed data. Has evolved into 3.5 generations. Furthermore, international standardization for 4G communication is currently in progress.

In the wireless communication system based on the 4th generation, robustness is required not only for data transmission speeds of 600 Mbps for downlink and 270 Mbps for uplink but also for mobility in the 40 MHz frequency band.

However, due to the influence of the high Doppler frequency due to the high-speed movement, the reliability of the channel prediction is drastically degraded. Not good. As a result, the target transmission rate cannot be set high enough.

In order to improve the factor of performance degradation of fading due to the high Doppler frequency, it is necessary to adopt a multiple antenna technology. A representative example of the multiple antenna technology is the MIM0 technology. At this time, even if the number of EII not used varies depending on the type of terminal, it must be compatible with the base station without changing the circuit structure, and a simple and economical design is basically required.

In addition, MIM0 technology, which supports multiple users to increase transport channel capacity by the number of antennas 1 and number, has also been proposed. However, at high speeds, there is a demand for MIM0 technology, which fundamentally supports new multi-users.

The MIM0 technology supporting the multi-user should be able to optimize subchannel allocation and power allocation in consideration of fairness among users according to different service requirements, transmission air quality, and channel state. In addition, OFDM or OF is a key technology to solve the problem of Peak-to-Average Power Ratio (PAPR) in WIA technology.

Considering the above, if the existing techniques for solving the 4th generation wireless communication system are comprehensively examined, there is a frequency equalizer that can be easily applied to MIM0 and OFDM as a technique for obtaining the diversity EI effect. But in high speed mobile system Due to the poor reliability of channel prediction, the structure of the pilot channel to improve this becomes more complicated. In addition, if the channel prediction is premised, the performance deteriorates rapidly or the complexity of the circuit makes it very difficult to increase the number of antennas to improve the performance.

On the other hand, in the case of uplink, it is easy to improve the reception performance through the maximum ratio combining using the channel for each receiving antenna in the base station, but in the case of the downlink, channel prediction is difficult or complicated. It will rise. In addition, MIM0 technology for supporting multiple users in uplink is difficult to maintain orthogonality between users in a channel, and thus multiple access interference is inevitably present. Therefore, it is perceived as unrealistic to implement in terms of system complexity, such as the need for additional multiuser detection technique to remove it.

However, in the case of downlink, since the orthogonality between users in the channel is relatively easily maintained in the case of a low-speed mobility channel, zero-forcing interference cancellation I at ion, 圆 SE co th coord inat ion, Matched A pre-spatial space coding scheme for filtering has been studied.

However, in the case of a high-speed mobility channel, the channel state itself changes inaccurately, so the channel prediction itself remains inaccurate. The MU-MIM0 technology standard, which is limited to low-speed mobility, is a high-speed mobility communication channel. MU-MIM0 for When technology is developed, it is envisaged to be replaced by new standards. As a method for avoiding the difficulty of channel estimation in downlink, the base station predicts a reception channel and then performs channel prediction on a transmission channel using the predicted signal and then uses the beam based on the prediction. There is beam forming technology. However, this also has a weak point in the packet communication method in estimating the channel.

In addition to the general power control depending on the position of the terminal, power control under the influence of fading is being studied, but this is limited to linear channel estimation, and the effectiveness of the mobile communication is rapidly deteriorated. In addition, the closed-loop power control technique requires much channel state information in the case of a high-speed mobile communication system as well as a complexity, causing a drastic drop in channel transmission efficiency.

On the other hand, there are compensating techniques for frequency offset at the receiver due to the Doppler frequency, which is vulnerable to the OFDM system, but the performance improvement is insufficient in the frequency selective fading channel.

In general, all bands of a wireless communication system have frequency selective channel characteristics. As a technique for maximizing the channel capacity of a wireless communication system, a subchannel allocation method and a power allocation method based on a water-filling method are mainly studied. Being. However, if the frequency characteristics of the channel change rapidly, It is required and practically not easy to apply. In addition, SC-FDMA technology is a technique for dramatically reducing the PAPR in the uplink and requires a favorable frequency domain equalizer under the influence of inter symbol interference, but at the receiving end, the frequency domain equalizer is required. The frequency diversity effect is obtained in the frequency selective fading channel because the output signal is despread by the IDFT. In addition, since the signal detection is averaged by the noise signal flowing in the frequency band of the entire system, it is known that the performance is better than OFDM or 0FDMA, and especially has an advantage in frequency offset (frequency offset).

As can be seen from the foregoing, for the 4G wireless communication system, it is necessary to provide a stable high speed data communication even in a high Doppler frequency fading environment.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the uplink / downlink link in improving channel performance, increasing transmission speed, increasing channel capacity of system, PAPR reduction method, subchannel allocation and power allocation. We propose the most efficient data transmission / reception apparatus and method.

In addition, the present invention transforms the frequency characteristics of the channel gain into a flat channel by using a differential space-time coding technique using multiple antennas in the downlink, and adaptive DFT We propose a data transmission / reception apparatus and method for compressing the transmission symbol in the frequency domain using the ring to increase the transmission rate of the channel and the channel capacity of the system to the maximum possible mathematically within the given transmission power range. do.

In addition, the present invention makes it possible to apply a differential space-time encoding technique using multiple antennas to QAM, and in the case of space-time decoding at the receiver, the channel gain is optimally and contrast-coupled so that the frequency characteristic of the channel is high even in the case of fading of high Doppler frequency We propose a data transmission / reception apparatus and method for simple transformation into a flat channel. In addition, the present invention proposes a data receiving apparatus and method for improving the performance and complexity of the terminal by minimizing the channel prediction at the receiving end by applying a simple interpolation method in the case of a high-speed mobile system.

In addition, the present invention transforms the frequency characteristics of the channel gain into a flat channel using a multi-antenna, and then adaptively -DFT transforms the transmission symbol to more effectively reduce the PAPR than the DFT-transformed OFD (A). We propose a receiving device and method.

In addition, the present invention transforms the frequency characteristics of the channel gain into a flat channel by using multiple antennas, and then uses the adaptive -DFT-converted -0FDMA scheme for each user and uses the characteristics of the same frequency characteristics among the subcarriers in the subchannel. We propose an apparatus and method for transmitting and receiving data.

In addition, the present invention is a propagation loss (propagation loss) according to the distance for each user, By simplifying the subchannel allocation and power allocation considering only the time service and the non-real time service, we propose a data transmission / reception apparatus and method that can simply maximize the channel capacity of the entire system.

In addition, the present invention performs signal compression in the frequency domain by adaptive DFT transform OFDM or 0FDMA scheme between the transmission data symbols in the sub-channel assigned to each user to transmit multiple data symbols on the sub-channel at the same time, minimizing the PAPR and At the same time, we propose a day EI transmission and reception apparatus and method for maximizing channel capacity.

In a wireless communication system supporting an orthogonal frequency division multiple access scheme according to an exemplary embodiment of the present invention, an apparatus for transmitting data in a high Doppler frequency fading environment includes a method of performing discrete Fourier transform on a raw symbol generated by a predetermined modulation scheme. A frame constituting a frame based on a raw spread symbol matrix on a predetermined subcarrier by inputting an adaptive discrete cluster to output a spread symbol, a raw spread symbol output from the transformer to the adaptive discrete cluster, and a sequence sequence. And a differential space-time encoder for generating a transmission symbol matrix in the predetermined subcarrier through encoding a raw spread symbol matrix of a frame constituted by the frame composer and the frame composer, and converting the generated transmission symbol matrix into the predetermined subcarrier. Fourier stools after mapping to And it transmits via a plurality of antennas.

In a wireless communication system supporting an orthogonal frequency division multiple access scheme according to an embodiment of the present invention, a method for transmitting data in a high Doppler frequency fading environment is provided. Outputting a raw spread symbol by converting a raw symbol generated by a predetermined modulation scheme into a discrete group, and outputting a raw spread symbol by one training sequence as the inputted raw spread symbol and one training sequence A process of constructing a frame, generating a transmission symbol matrix in the predetermined subcarrier through encoding of the raw spread symbol matrix force of the configured frame, and mapping the generated transmission symbol matrix to the predetermined subcarrier Pohang the process of transforming into a high speed flock and transmitting through multiple antennas.

In a wireless communication system supporting an orthogonal frequency division multiple access scheme according to an embodiment of the present invention, an apparatus for receiving data in a high Doppler frequency fading environment includes a received signal received on a predetermined subcarrier after a conversion is performed to a group; A differential space-time decoder for outputting a raw spread symbol matrix through differential space-time decoding on the received signal with a channel prediction value and a self-generated raw spread symbol, and from a raw spread symbol matrix output by the differential space-time encoding A frame separator for separating a raw spread symbol and a training sequence, a channel predictor for predicting a channel state by a training sequence separated by the frame separator, and providing a channel prediction value to the differential space-time decoder; Invert the separated raw spread symbol An adaptive inverse discrete Fourier transformer for converting a mountain group to output a raw symbol and a received data S obtained through signal determination on a raw symbol output from the adaptive inverse discrete Fourier transformer are generated by converting the received data S into a discrete group. Raw spread seam And a transducer in an adaptive discrete cluster that provides a to the differential space-time decoder. In a wireless communication system supporting an orthogonal frequency division multiple access scheme according to an embodiment of the present invention, a method for receiving a day S in a high Doppler frequency fading environment includes a received signal received from a predetermined subcarrier after a conversion is performed to a group. A process of outputting a raw spread symbol matrix through differential time-space decoding of the received signal by inputting a channel predicted value and a self-generated raw spread symbol. The raw spread symbol and δ are output from the outputted raw spread symbol matrix. And a step of generating a channel prediction value by estimating a channel state by the separated S sequences. A process of outputting a raw symbol by inverse discrete Fourier transform of the separated raw spread symbol. And, the received data Θ obtained through the signal determination on the output raw symbols The acid Fourier transform comprises the step of the call themselves (generating a raw spread symbols.

In the scheduling method for resource allocation in a multi-antenna system supporting multiple users according to an embodiment of the present invention, assuming that the frequency characteristics of subchannels allocated to the maximum ratio combined terminals are the same, the inverse of the signal-to-noise ratio Is arranged in a large order from the sub-channel of the small terminal, the minimum power to satisfy the quality of service in the case of real-time service according to the order based on the arrangement, and in the case of non-real-time service Pouring the process of allocating power to all terminals in consideration of the distance. In the following description, detailed descriptions of well-known functions or configurations related to the present invention will be omitted if it is determined that the gist of the present invention may be unnecessarily obscured. Terms to be described later are terms defined in consideration of functions in the present invention, which may vary depending on the intention or management of a user or an operator. Therefore, the definition should be made based on the contents throughout the specification.

In the embodiment of the present invention for designing a high-speed mobile communication system to be described later, it is determined that high Doppler frequency fading and PAPR in uplink are essential tasks to consider the correlation of element technologies in terms of the entire system. something to do.

Since the downlink does not require channel prediction, the differential space-time coding technique, which is known as the most effective technique for improving the performance due to the high Doppler frequency fading effect, is applied. However, it is possible to solve the detection error flow phenomenon in the QAM channel with high modulation index by complementing the diffusion of other detection errors while predicting and reflecting the time-varying characteristics of fading within the frame. Look at it from the perspective II.

In addition, by using a space-time encoding technique, the frequency-selective fading channel becomes a flat channel according to the maximum ratio of the reception channels, and thus the transmission symbol is transmitted in the frequency domain by adaptive DFT conversion OFDM or 0FDMA. By compression We propose a method to increase the transmission speed of a channel and the channel capacity of a system as much as possible freely within a given transmission power range.

That is, when the position of the terminal is located near the base station, the strength of the received power is

As it is increased to 40 dB / dec, it is a method for utilizing the received power usefully.It is a method of compressing and transmitting a signal in the frequency domain by adaptively performing DFT conversion according to the strength of the received power, and restoring it in reverse at the receiving end. Detect the living signal. In general, OFDM that supports DFT conversion not only makes the channel gain of reconstructed symbols uniform, but also has very good PAPR for flat channels that are not affected by fading.

Therefore, in the present invention, the frequency-selective fading channel is flat channeled as the state of the reception channel is optimally combined by the space-time coding technique, and the PAPR is applied to the conventional simple DFT by applying the adaptive DFT transform OFDM or 0FDMA. PAPR can be reduced more efficiently than transform OFDM.

In the uplink, the channel performance is improved by the reception diversity scheme in consideration of the number of antennas appropriate for the terminal and the complexity acceptable in the base station. Select and apply PAPR reduction technology that has low channel performance degradation.

In the uplink, since orthogonality is not maintained between users, a dedicated subchannel is allocated to each user in consideration of the required transmission amount, and the terminal has the maximum. Multiplexing in the frequency domain with adaptive -DFT spreading code within the high power range. This significantly increases the transmission capacity of the uplink system while avoiding frequency overlap with other users within the available power range of the terminal.

In addition, sub-channel allocation and power allocation should be optimized in consideration of equity among users according to service type, required transmission speed, transmission quality, and channel condition. Therefore, considering the maximum S / N ratio for each subchannel due to the maximum ratio combining and frequency domain diffusion resolution in the downlink, the consideration of frequency characteristics is excluded. In addition, it is possible to easily maximize the channel capacity by applying only the water-filling technique according to the position of the terminal. In this case, it is assumed that all terminals are uniformly distributed in the long term from the center of the base station, thereby simplifying the problem by eliminating the consideration of equity among the terminals.

In addition, performance is maximized in consideration of system complexity and required transmission speed according to characteristics of uplink and downlink. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

A. Day a transmission / reception apparatus and method

In an embodiment of the present invention, the transmission / reception for transmitting data through the downlink An apparatus is proposed as a first embodiment, and a transmission / transmission value for transmitting data through uplink is proposed as a second embodiment.

In the first embodiment of the present invention will be described in detail with respect to the apparatus and method for transmitting or receiving data by applying the differential space-time coding technique and the PAPR reduction technique in the downlink. In the second embodiment of the present invention, an apparatus and method for transmitting or receiving data by applying a space-time block coding technique and a PAPR reduction technique in uplink to increase channel capacity will be described in detail.

A-1. First embodiment (downlink data transmission)

1 shows an apparatus for transmitting / receiving day Ei through downlink in a wireless communication system supporting an orthogonal frequency multiplexing scheme according to an embodiment of the present invention. It consists of adaptive -DFT transform / inverse transform OFDM (A) and 4 transmit antennas and 2 receive antennas for improving channel performance, increasing channel capacity and reducing PAPR in downlink under high Doppler frequency fading environment. The MIM0 system based on the differential space-time coding scheme is shown.

As shown in FIG. 1, a base station according to an embodiment of the present invention includes a transmission day a 101, a modulator 102, an adaptive -DFT spreader 103, a frame configurator 104, and a training sequence generator 105. ), A differential space-time encoder 106, a subcarrier mapper 107, and an IFFT inverse transformer 108. The terminal includes the FFT transformer 109, the subcarrier demapper 110, the differential space-time decoder 111, the frame separator 112, the summer 113, and the positive / negative band analysis signal generator 113-2. Bottle / serializer (113-1) Serial / parallel (113-3), adaptive -IDFT inverse diffuser ("4), demodulator (115), modulator (116), multi-DFT diffuser (117) for post-processing Channel predictor 118.

1, the modulator 102-1 inputs a plurality of transmission data EIs and modulates the input plurality of input data by a predetermined modulation scheme. The ^ th raw symbol generated through the modulation is output.

Adaptive DFT Spreading Unit (103) performs a transform on the discrete set of raw symbols provided from the modulator 102-1 to output the raw spreading symbols. A detailed description of the adaptive DFT transform OFDM (A) for generating the raw spread symbol through the transform on the discrete group will be described later. The raw spread symbol is provided to frame configurator 104.

Training Sequence Unit 105 generates a training sequence that will be used to predict the channel environment. It is common for the sequence to have a form and signal strength promised in advance & end.

The Frame Frame Unit 104 takes as input a raw spread symbol provided from the adaptive -DFT spreader 103 and a training sequence provided from the training sequence generator 105. And the raw spread symbol and the training sequence Frames are composed by For the frame configuration, the frame configurator 104 generates a raw spread symbol matrix on a given subcarrier. That is, it generates the first raw spread symbol matrix ^S " in the second subcarrier. The raw spread symbol matrix generated by the frame configurator 104 will be described in detail later.

Differential ST Coding Unit 106 generates a transmission symbol matrix through the encoding of the raw spreading seam S matrix of the frame configured by frame constructor 104. In other words, by encoding the ^ th raw spread symbol matrix on the th subcarrier, the th transmit symbol matrix ^x " on the / th subcarrier is generated. A detailed scheme for generating the transmit symbol mattress will be described later.

The subcarrier mapping unit (10) maps and transmits the transmission symbol matrix ^X generated by the differential space-time encoder 106 to the second subcarrier, which is the corresponding subcarrier.

Inverse group transform units IFFTK108-1 to 108-4 transmit on the subcarrier, i.e., the subcarrier, to which the transmission symbol matrix β mapping provided to the subcarrier mapper 107 is provided. In this case, the transmission symbol matrix is transmitted on a corresponding subcarrier through a transmission scheme Ell corresponding to each of the IFFT units 108-1 to 108-4.

Meanwhile, the transmission signal transmitted through the downlink by the above-described procedure is transmitted to the terminal. Is received. The terminal may be provided with one or a plurality of receiving antennas. Degree

In FIG. 1, it is assumed that one receiving EII is included, but when two receiving E1Is are included, a configuration indicated by a dotted line in FIG. 1 may be added. Even in the case of having a plurality of receiving antennas, the additional configuration performs the same operation as that in the case of having one receiving antenna I. Therefore, in the following description, only one configuration will be described, but it is apparent that a configuration that can be added corresponding to other receiving antennas should perform the same operation as described below.

The Fourier transform unit (FFT) 109-1 constituting the terminal receives a received signal through a receive antenna. The FFT 09-1 converts the received signal into a group and outputs the received signal by converting the received signal into a signal in a time domain.

The subcarrier de-mapping unit 110-1 selects and outputs only a signal transmitted by a corresponding subcarrier to be received from the received signal in the time domain.

Differential ST Decode Unit 111-1 receives a received signal output from the subcarrier demapper 110, a channel prediction value, and a self-generated raw spread symbol. The differential inter-space decoding is performed on a signal received by the desired subcarrier in consideration of the channel axis value and the self-generated original spread symbol. A detailed description of the differential space-time decoding on the received signal will be described later. The differential space-time decoder 111-1 receives the received signal. A raw spread symbol matrix is obtained through differential space-time decoding of.

Meanwhile, the channel prediction value is provided by a channel estimator 118-1, and the self-generated original spreading symbol is provided by a multi-DFT spreader 117.

Dessemble Frame Unit 112-1 Separates and outputs a raw spread symbol and a training sequence from a raw spread symbol matrix output by the differential space-time decoder 111-1. The separated raw spread symbol is passed to a sum unit 113, and the separated serial sequence is passed to the channel predictor 118-1.

The channel predictor 118-1 predicts the channel state of the downlink by the training sequence transmitted from the frame separator 112-1. The channel prediction value corresponding to the predicted channel state is provided to the differential space-time decoder 111-1.

On the other hand, when the summer 113 is provided with a plurality of receiving antennas, the raw spread symbols provided by the EH from the frame separators 112-1 and 112-2 provided corresponding to each receiving antenna are input. The raw spread symbols provided from the plurality of frame separators 112-1 and 112-2 are summed and output. However, if the terminal is provided with one receiving antenna, the summer 113 may be an unnecessary configuration.

The raw spread symbols output in parallel by the summer 113 are output in one raw spread symbol sequence by the parallel / serial converter P / SH113-1. The serial type The raw spread symbol sequence transformed into the form is a negative / positive frequency band analysis signal generator.

(Positive / Negative Frequency Analytic Signal Generator) 113-2. The negative / positive frequency band analysis signal generator 113-2 separates an analysis signal of a positive or negative frequency component of the serial type spread symbol sequence and outputs the analyzed signal.

The serial-type signal EI output from the negative / positive frequency band analysis signal generator 113-2 is converted into a signal having a parallel form by the serial / parallel converter S / PK113-3 and output. The parallel signal output from the S / P converter 113-3 is transferred to an adaptive IDFT despreading unit 1.

The adaptive -IDFT despreader 114 performs a transform on the inverse discrete group for the raw spread symbols output from the S / P converter 113-3 to output the raw symbols. A detailed description of the transform in the inverse discrete cluster performed by the adaptive -IDFT despreader 114 will be described later.

The decoder for the raw symbols obtained through the transform into the inverse discrete group

Decoding is performed by 115. That is, the received data 119 is obtained through signal determination on the original symbol.

On the other hand, the received data obtained through the determination in the decoder 115 is a modulator.

It is delivered to 116 and modulated to the raw symbols by the same modulation scheme as used at the base station. And the raw symbols output by the modulator 116 are adaptive Frequency spreading is performed by the DFT spreader 117, and is obtained from the original spreading symbol from which the frequency spreading is performed. The obtained is provided to the differential space-time protector 111-1.

As described above, in the apparatus and method for transmitting data according to the first embodiment of the present invention, adaptive DFT spreads modulation symbols, configures them as frames, and transmits them through differential space-time encoding. In the data receiving apparatus and method corresponding thereto, after performing differential space-time decoding on a received signal, a frame is decomposed, and a raw symbol is obtained by adaptive IDFT despreading on a raw spread symbol obtained through the frame decomposition. .

A-2. Second Embodiment (Uplink Day Θ Transmission)

2 illustrates an apparatus for transmitting / receiving data through uplink in a wireless communication system supporting an orthogonal frequency multiplexing scheme according to an embodiment of the present invention. That is, based on spatiotemporal coding technique consisting of an adaptive -DFT spreader and 4 transmit antennas and 2 receive antennas for improving channel performance, increasing channel capacity, and reducing PAPR in uplink in high Doppler frequency fading environment. The configuration of the MIM0 system is shown.

As shown in FIG. 2, a terminal according to an embodiment of the present invention includes a transmission data 201, a modulator 202, a serial / parallel converter 203, an adaptive -DFT spreader 204, and a frame configuration. Group 205, five sequence generators 206, space-time convex encoder 207, subcarrier mapper 208, and IFFT inverse transformer 209.

And a base station ^ FFT converter 210, a subcarrier demapper 211, a space-time block decoder 212, a channel prediction and maximum ratio combiner 213, a frame separator 214, a negative / positive frequency band analysis signal generator ( 214-2), bottle / serial converter 214-1 and serial / parallel converter 214-3, adaptive -IDFT despreader 215, bottle / serial converter 216, demodulator 217 .

2, the modulator 202 takes a transmission day E1 as an input and modulates the input transmission day S by a predetermined modulation scheme. And outputs the th raw symbol D * generated through the modulation. The raw symbols provided from the modulator 102-1 are output as parallel raw symbols by the serial / parallel converter 204.

An adaptive DFT Spreading Unit 204 converts the discrete clusters of the raw symbols D * provided from the S / P converter 203 to output the raw spread symbols. A detailed description of the adaptive DFT transform OFDM (A) for generating a raw spread symbol by transforming the discrete cluster will be described later. The prime L spread symbol is provided to a frame configurator 205.

Training Sequence Unit 206 generates serial sequences to be used to predict the channel environment. The training sequence typically has a form and signal strength previously agreed upon with the terminal. The Frame Frame Unit 205 takes as input a raw spread symbol provided from the adaptive -DFT spreader 204 and a training sequence provided from the training sequence generator 206. The frame is constructed by the raw spread symbol and the training sequence. For the frame configuration, the frame configurator 205 generates a raw spread symbol matrix on a given subcarrier. That is, it generates the i th proliferation symbol matrix ^ on the th subcarrier. The raw spread symbol matrix generated by the frame configurator 205 will be described in detail later in the description.

The space-time block coding unit 207 generates a transmission symbol matrix through encoding of the raw spread symbol matrix of the frame constituted by the frame constructor 205. In other words, by protecting the first raw spread symbol matrix on the first subcarrier, the second transmission symbol matrix ^X " on the second subcarrier is generated. A detailed scheme for generating the transmission symbol matrix will be described later.

The subcarrier mapping unit 208 maps and transmits the transmission symbol matrix ^X generated by the space-time convex encoder 207 to the Z-th subcarrier, which is the corresponding subcarrier.

Inverse group transform units IFFTK209-1 to 209-2 convert sub-carriers, i.e., sub-carriers, to which the transmission symbol matrix provided from the sub-carrier mapper 208 is mapped. Send from the wave. In this case, the transmission symbol matrix is transmitted on a corresponding subcarrier through a transmission antenna corresponding to each of the IFFT units 209-1 to 209-2.

Meanwhile, the terminal may have one or more I reception EII. In FIG. 2, it is assumed that one receiving antenna is provided, but when two receiving antennas are provided, a configuration indicated by a dotted line in FIG. 2 may be added. Even in the case of having a plurality of receiving antennas, the additional configuration performs the same operation as the configuration in the case of having one receiving EII. Therefore, in the following description, only one configuration will be described, but it is apparent that a configuration that can be added corresponding to other receiving antennas should perform the same operation as described below.

Meanwhile, the transmission signal transmitted through the uplink by the above-described procedure is received by the base station.

The conversion unit FFTH210 is provided with a reception signal through a reception antenna in a group provided for each reception antenna in the base station. The FFT 210 converts the received signal into a group of the received signal and outputs the converted signal.

The subcarrier de-mapping unit 211 selects and outputs only a signal transmitted by a corresponding subcarrier desired to be received from the received signal in the time domain.

A ST block decoding unit 212 is used to demap the subcarrier. Space-time block decoding is performed on the received signal output from the ping machine 211. A detailed description of the space-time block decoding on the received signal will be described later. The space-time convex decoder 212 obtains a raw spread symbol matrix through space-time block decoding on the received signal.

Channel Estimation MRC Combing Unit 213 estimates the channel state of the uplink from the raw spread symbol matrix. The channel prediction value corresponding to the predicted channel state is obtained. In addition, the channel prediction and maximum ratio combiner 213 performs a function of converting a frequency selective fading channel into a flat channel.

A dessemble frame unit 214 separates and outputs a raw spread symbol and a sequence from a raw spread symbol matrix converted into a flat channel by the channel prediction and maximum ratio combiner 213. The separated raw spread symbol is converted into a serial signal by a bottle / serial converter 214-1 and transmitted to a positive / negative frequency analytic signal generator 214-2. do.

The negative / positive frequency band analysis signal generator 214-2 separates and outputs the positive or negative frequency band analysis signal of the serial spread symbol sequence.

Serial form output from the negative / positive frequency band analysis signal generator 214-2 The signal of is converted into a signal having parallel form by the serial / parallel converter (S / PH214-3) and output. The parallel signal output from the S / P converter 214-3 is transferred to an adaptive IDFT de-spreading unit 215.

The adaptive-IDFT despreader 215 performs a transform on the inverse discrete cluster for the raw spread symbols output from the S / P converter 214-3 to output the raw symbols. A detailed description of the inverse discrete Fourier transform performed by the adaptive -IDFT despreader 215 will be described later.

The raw symbols obtained through the Inverse Discrete Fourier Transform are converted into serial raw symbols by the parallel / serial converter 216 and then decoded by the decoder 217. In other words, the received data 218 is obtained through signal determination on the original symbol.

As described above, in the data transmission apparatus and method according to the second example I of the present invention, an adaptive DFT spreads a modulation symbol, configures it as a frame, and transmits it through space-time block encoding. In the data receiving apparatus and method corresponding thereto, after performing space-time block decoding on a received signal, a frame is decomposed, and a raw symbol is obtained through adaptive IDFT despreading on a raw spread symbol obtained through the frame decomposition. .

3 is a diagram illustrating a conventional conventional water-filling technique, so that less power is allocated to a terminal having a good signal to noise ratio. And fill the water As you can see, allocating power within an acceptable range of power is known as an algorithm that maximizes the processing capacity of the system.

4 shows an example of power allocation based on the conventional water-f i 11ing technique. First, the optimal allocation is difficult because the S / N curve changes very quickly in the high-speed mobile communication channel. In addition, even when attempting to allocate the maximum power to a nearby terminal because the maximum transmission rate is determined, power allocation is bound to be limited. Therefore, maximization of channel capacity of the system cannot be achieved.

5 is a view for explaining a power allocation technique according to an embodiment of the present invention. In FIG. 5, ^ and ^ refer to a real-time service channel, and others refer to a non-real-time service channel.

In this case, the non-real-time service allocates the maximum power that can be allocated, and the corresponding Dalral can maximize the transmission speed by maximizing the allocated power by the adaptive DFT-conversion method. In the real-time service channel, only power in a range satisfying the required QoS is allocated.

In addition, since the embodiment of the present invention uses MIM0 and the adaptive -DFT, the frequency characteristic of the channel is flat, which is very simple because only the power allocation for the distance between the base station and the terminal needs to be considered.

B. Specific implementation for data transmission / reception over downlink Hereinafter, a specific embodiment for the first and second embodiments of the present invention will be examined. That is, the differential space-time encoding technique and the PAPR reduction technique provided for data transmission / reception in downlink according to the first embodiment of the present invention will be described in detail. In addition, the spatiotemporal block coding technique and the PAPR reduction technique provided in data transmission / reception in order to increase the channel capacity in the uplink according to the second embodiment of the present invention will be described in detail.

B-1. Differential Spatio-temporal Coding and PAPR Reduction in Downlink

In order to process high Doppler frequency fading in the downlink where channel prediction is difficult, MIM0, which is a differential space-time coding method that can avoid channel prediction, may be most effective and necessary. In order to clearly improve the performance, it is desirable to maintain independent relationships between channel gains received by various antennas of the terminal. However, even if the distance between the antennas within the terminal can be sufficiently separated, it is difficult to maintain the mutually independent relationship according to the operation of the terminal. Therefore, it is assumed that 4 base station antennas and 1 terminal antenna are the most realistic structures, and 2 terminal antennas are also compatible.

In general, the differential space-time coding technique in PSK Rayleigh fading channel is 3 dB worse than the coherent method in terms of performance improvement, but is very advantageous in terms of circuit complexity. This technique has been developed as a differential space-time coding technique for QAM to detect signals Although the results of the method have been published, embodiments of the present invention maximize the performance improvement by applying interpolation to the time-varying characteristics of the channel gain in the frame according to the high Doppler frequency. In addition, after the FFT processing at the receiver, the detection error can be corrected by the convolutional decoder by using the characteristic that the cluster error is spread during the process of serial conversion. This minimizes the error propagat ion.

In addition, in the description of an embodiment according to the present invention, for convenience, assume a 2 Tx X 1 Rx antenna compatible with 1 Tx X 1 Rx.

According to the above assumption, in the OFDM (A) system, the first raw symbol matrix of each subcarrier is defined as s _k 'transmission symbol matrix as ^x * as shown in Equation 1 below.

[Equation 1]

^X 2k ^S 2k

*

_ ᅳ ½. _ ~ ^S 2k Here, the first row of the symbol matrix means the first symbol, and the first column means the symbol transmitted through the first antenna.

When defined as shown in Equation 1, the differential space-time coding applicable to QAM can be normalized by the power of ^χ * -ι, that is, Frobenius Norm Ai as shown in Equation 2 below.

[Equation 2] According to the normalization as shown in Equation 2, a relationship as shown in Equation 3 is established.

[Equation 3]

i = \\ ^ l = \ t

In this case, each of the reception symbol matrix ^R *, the channel gain matrix H *, and the white noise ^N * flowing into the channel may be defined by Equation 4 below.

[Equation 4]

The reception core S DH trix ( ^K *) may be expressed by Equations 5 and 6 below.

[Equation 5]

[Equation 6]

Here, () ^W means Hermitian.

Thus, assuming that ^Η * ^≡Η * — ^,, Equation 7 obtained from Equation 5 and Equation 6 is converted into Equation 8 below.

[Equation 7]

[Equation 8]

The result of the conversion by Equation 8 is a constant of the channel gain combined with the maximum ratio.

The channel gain combined with the maximum ratio required by Equation (8) is converted from Equation (9) to Equation (12) and finally obtained by Equation (13).

[Equation 9]

[Equation 10]

[Formula]

Formula

[Equation 13]

The equations contain noise. In addition, because of the maximum ratio using multiple antennas, the channel gain varies linearly and simply within the frame even with high Doppler frequency fading. This phenomenon can be confirmed experimentally.

On the other hand, in order to minimize the detection error spreading phenomenon, it is necessary to accurately predict the combined channel gain. To this end, a method using a training sequence is most reliable. In this case, linear interpolation can be used for channel prediction in the symbol interval existing between five training sequences.

Equation 11 shows the channel gain l ^ u | ² + * | ² can be predicted, and w is the length in OFDM symbols of the frame, the channel prediction in the symbol interval between 5 sequences as shown in Equation 12 is linear You can get it using (interp ation). In this case, it is possible to minimize the weak characteristics of the noise and the problem of spreading the detection error. Meanwhile, four transmission antennas and one reception antenna (4TXX 1RX) scheme use the transmission symbol matrix defined by Equation (14) below.

[Equation 14]

In general, the base station does not have a severe PAPR requirement, but if the PAPR needs to be reduced, it may be based on the DFT-transformed OFDM technique among PAPR reduction techniques, which could not be used due to the degradation of the channel due to the high Doppler frequency fading. have. In the present invention, an adaptive -DFT-converted OFDM (A) is proposed to minimize the PAPR while minimizing channel performance degradation. Here, the adaptive DFT-converted OFDM will be described in detail below. In an embodiment of the present invention, an adaptive -DFT-converted OFDM (A) is proposed so that PAPR can be minimized while minimizing channel performance degradation. Detailed description of the adaptive -DFT-converted OFDM (A) will be described later.

1) Adaptive DFT Transform OFDM (A)

In order to simplify the description of the design fixability of the adaptive DFT change OFDM system in the uplink or the downlink, a 2 Tx X 1 Rx antenna compatible with 1 Tx X 1 Rx is assumed. According to the above assumptions, the following equations (15) to (19) perform DFT transformation from the raw seam: to the M level for generating the raw diffusion matrix. 【Number

[Equation 16]

[Equation 17]

[Equation 18]

[Equation 19]

Where each element makes up the first primitive symbol sequence ^D * ⁼ { ^dQ ' ^di '^'"' ^d "} * Is N}

Uses a fixed value. In this case, M means a DFT conversion level determined according to the strength of the received signal, and N represents the DFT size.

Meanwhile, ² may be expressed as in Equation 20 below.

[Equation 20]

N

'= 1 ~ where the th raw spread symbol at the ^ th subcarrier is ^{s &} ffl, B _pM is the positive frequency signal, B „ _M! Means frequency signal of §

As another embodiment, without using the above-described Equations 15 to 19, Μ for generating a raw spreading matrix from a raw symbol by Equations 21 to 26 below. DFT conversion is performed up to the level.

[Equation 21]

4i _0n e ^N + ∑b _0n e ^N , / = 1 ~ -— 1

[Equation 22]

A = 2∑a _ln e ""- ₊ 2∑b e- ^

[Equation 23]

Equation 241

[Equation 25]

、、

A ^(M- ^!) = ∑Re Mr e + Ylm A ^(A) e + ∑ e A ^(M - ²⁾ e ^~ + A ^(M — ²⁾ ^ ᅳ ᅳ, l = l ~ --Xm = Q, l

A ^(M → = 2¾¾iA ' ^M -e ^iOT + 2f iA ^(M -e ^ + 2¾

On the other hand, _A i _{= 1} JL can be represented by the following equation (27).

° ', 2

[Equation 27]

Wherein Z th la raw spread symbol ^Λ in the sub-carrier, and is a positive signal can ¬¬, ^Α: ./ refers to the frequency signal of the sound.

2) Differential Spatio-temporal Mining / Decoding Techniques for OFDM (A) Downlink A second source diffusion symbol matrix at the Z-th sub-carrier, if defined as a transmission symbol every bit ryeokseu and below ^Χ Ά <Equation 28>, QAM encoding liver also applicable differential construction is X "- ¹ power that is Frobenius Norm ^Ρι of In consideration of this, it can be normalized as shown in Equation 29. With this normalization, the relationship of Equation 30 is established.

[Equation 28]

S,

[Equation 29]

[Equation 30]

Where is the power allocated per subcarrier of the »ι-th user. Thus, after the FFT processing and the subcarrier mapping process of the signal received from the receiver I or the receiver, the received signal mat force is expressed by Equations 31 to 33 below.

[Equation 31]

[Equation 32] [Equation 33]

^R l, k-1 to ⁿ l, l ^A l, kl 一 1

Where ^R * denotes the mth received symbol matrix at the th subcarrier,

^H means channel gain matrix, and ^Ν '* means white noise flowing into the channel. And () "means Hermitian.

Thus, assuming Ι ^Η Ι ^≡ Ι ^Η " ^-ι |, the following Equation 34 obtained from Equation 32 and Eq. 33 is converted into Equation 35. It becomes a function of the maximum ratio combining channel gain.

(Equation 34) t— + X _ft H _tt N knee)

[Equation 35]

S¾ = _j —-~ -— | Y ( ^R tt ^R -i— Nft ^N ui ^_ ( ^N tt ^H tt ^X -i ⁺ Xtt ^H tt ^N -i)) The maximum ratio combined channel gain required by Equation 35 is expressed by Equation 36 It can be calculated | required by converting into <Equation 40>from>.

[Equation 36] 37】

[Equation 38]

[Equation 40]

^-R a

5 (, ² +, * ᅴ ² )

Equations (36) to (40) include noise. In addition, since the maximum ratio is combined using several eye Eils, even in the case of high Doppler frequency fading, the channel gain varies linearly and simply within the frame. This phenomenon can be confirmed experimentally.

On the other hand, in order to minimize the detection error spreading, the combined channel gain must be accurately predicted. For this, the method using the training sequence is most reliable. Interp can be used.

Thus, as shown in Equation 38, the channel gain is predicted using the sequence sequence. When W is the length in units of OFDM symbols of a frame, the channel prediction in the symbol interval existing between training sequences is obtained by using linear interpolation, as shown in Equation (33). The vulnerable nature of the noise and the diffusion problem of the detection error can be minimized.

3) Inverse transform scheme of adaptive DFT transform OFDM (A)

As shown in Equation 40, the first received symbol, which is differential space-time decoded by the receiver, is simply referred to as " for convenience of explanation. And ^S P ¹ is the output signal of the positive frequency band analytic signal generator, and is the output signal of the negative frequency band analyt ic signal generator, where " ^{= 1} ~} can be obtained by Equation 41 below. have.

[Equation 41]

∑

Equations (42) and (43) provide the basis on which Equation (41) is developed.

[Equation 42]

[Equation 43]

= 1 ~ N 44>. [44]

= + s _nl = ∑a „e ^~ + ∑l, l = l ~ N

[Equation 45]

Formula

2,

-∑ ᅳ Σ

Thus, using the inverse transformation method of Equations 41 and 44,

N_

Sequentially from 2 n + iK _n

I "= 1 ~ N} can be obtained.

Alternatively, using the inverse transformation method of Equations 41 and 44,

N

sequentially from ί 」

Κ + _0η I "= 1 ~ N}, {a _ln + jb | n = l ~ N} ..., {^ + jb _mn |« = 1 ~ N}, ..., {a _Mn + jb _Mn 11 ~ N} In this case, in the 4TXX 1RX antenna scheme, when the first raw spreading symbol matrix in the ^ th subband ¾ carrier is ^S 'transmission symbol matrix X " Use it like this:

[Number βί-ΛΙ 4Π

*

ᅳ

[Equation 48] n ΊΪ

ΊΪ 2 2

B-2 Space-Time Block Coding Technique and PAPR Reduction Technique for Increasing Channel Capacity Assuming 1Txx4Rx antenna in uplink,

,

There is an advantage of not doing the I side over the channel. However, the performance improvement is not satisfactory. Thus, considering the complexity of the base station is acceptable, the base station can perform channel estimation by using a training sequence for each reception date1 or each, and easily achieve the maximum ratio combining. In general, a reception diversity scheme is used, but channel time-varying characteristics due to high Doppler frequency fading improve performance by applying the third method according to Equation (12). In the uplink, on the other hand, maintaining orthogonality between users is not practically easy. Therefore, in the MU-MIM0 system, the interference between users is serious and multi-user signal detection to remove them is more difficult in terms of circuit complexity. Therefore, in order to significantly increase the channel capacity of the uplink, each user Rather than assigning multiple sub-channels to multiple sub-channels for sharing them, a single sub-channel is assigned to each user, and within the maximum power range of the terminal within the assigned single sub-channel. Adaptive-DFT code spreads in the frequency domain and multiplexes.

This will significantly increase the capacity of the entire uplink system while avoiding frequency overlap of other users within the available power range of the terminal.

1) Scheduling Scheme for Multi-User MIM0 System

In order to optimize the channel transmission capacity of the multi-user MIM0 system, subchannel allocation and power allocation are optimized in consideration of fairness among users according to service type, required transmission speed, transmission quality, and subchannel status. And using multiple antennas, the process is simplified by using the maximum ratio combined result at the receiver.

At this time, since the downlink traffic is considerably required from the point of view of the whole system, the channel characteristics of the subcarriers are considered in consideration of the average uniform S / N ratio according to the maximum ratio combining result in the downlink. Simplify by eliminating consideration. In addition, the channel capacity can be easily maximized by modifying and applying the existing water-f l ling method considering only propagation loss according to the position of the terminal of the channel.

At this time, all the terminals are uniformly distributed from the center of the base station for a long time. Simplify the problem by excluding the consideration of equity between terminals assuming that it is included.

2) Scheduling Technique

a. The frequency characteristics of the sub-channels of each UE with the maximum ratio are approximated to be the same.

b. The reciprocal of the S / N is arranged in descending order from the subchannel of the terminal.

c Starting from a terminal with a low reciprocal of S / N, the real-time service allocates the minimum power that satisfies the QoS and the non-real-time service applies the water-filling technique to reduce the total power. Repeat until all are allocated.

Mathematically, the water-finding technique has proven to maximize channel capacity when the overall power is constant. However, the Conventional Water-f l ling scheme excessively allocates power to a terminal close to a base station. In addition, in the case of a terminal located far away from the base station may not be able to allocate power.

Partial Constant Power Water-II IIing, which is a method proposed by the present invention, allocates the minimum power that satisfies the maximum demand transmission in case of real-time service, and the terminal located far from the terminal close to the base station in total power conditioning for non-real-time service Allocate power sequentially up to. This ensures the highest overall channel capacity while avoiding unnecessary excessive power allocation. Have an advantage. As described above, according to the embodiment of the present invention, in all communication systems based on the OFDM (A) technology, frequency domain multiplexing is performed to increase the transmission rate of the channel in an unlimited range within the allocated allowable power range. Can be. In the case of ultra-high-speed mobile communication system, it is possible to achieve diffusion or signal compression in the frequency domain by using adaptive space-time block coding combined with adaptive DFT change technique.

In addition, PAPR, subchannel allocation, and power allocation can be made very easy in the 4th generation mobile communication system, which greatly reduces the complexity of the system.

On the other hand, the preferred embodiment of the present invention has been shown and described, but the present invention is not limited to the specific embodiments described above, in the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims Various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

[Brief Description of Drawings]

1 is a diagram illustrating an apparatus for transmitting / receiving data through downlink in a wireless communication system supporting an orthogonal frequency multiplexing scheme according to an embodiment of the present invention. 2 illustrates an apparatus for transmitting / receiving data through uplink in a wireless communication system supporting an orthogonal frequency multiplexing scheme according to an embodiment of the present invention.

3 is a diagram illustrating a conventional conventional water-filling technique.

4 is a diagram showing an example of power allocation based on a conventional water-filling technique.

Claims

[Range of request]

[Claim 1] An apparatus for transmitting data in a high Doppler frequency fading environment in a wireless communication system g that supports orthogonal frequency division multiple access.

An adaptive discrete bunch converter that converts the raw symbols generated by the predetermined modulation scheme into discrete bunches and outputs the raw spreading symbols;

A frame configurator constituting a frame based on a raw spread symbol matrix on a predetermined subcarrier by inputting a raw spread symbol high-sequence sequence output from the adaptive discrete Fourier transformer; And

A differential space-time coder for generating a transmission symbol matrix on the predetermined subcarrier through encoding of a raw spread symbol matrix of a frame configured by the frame configurator,

And mapping the generated transmission symbol matrix to the predetermined subcarrier and converting the transformed symbol matrix into an inverse high speed cluster to transmit through a plurality of antennas.

Claim 2-The apparatus of claim 1, wherein the adaptive discrete herd is

By inputting the original symbol ^{D =} { ^d o ' ^di '^"'' ^d «} ¾ generated by the predetermined modulation scheme

of

Calculate the solution,

Where ^D constituting ^D is defined as ^{= (+} j ^{b: fl = 1} ~ w—i}, B _pM ^ positive frequency signal, „ _{M /} means negative frequency signal, Μ is the A data transmission apparatus, characterized in that the level of conversion to the discrete group determined by the intensity, Ν is the size for the conversion to the discrete group.

3. The method of claim 1, wherein the adaptive discrete transformer is

Input the raw symbols D * ^{^} do'di ^ 'dM generated by the predetermined modulation scheme.

≥ A primitive spreading symbol defined as = S _{ft +} ^ = A) = A ( ^M ) ₊ A ( ^M) , / = l ~ ^

^S lk _^

A ^(M) _m

A ^w = 2VRe A * "^{" 1} '+ 2Υΐπι A ^(M_,) k ^ ^{2 j} + 2∑Re to' ^m + 2∑Im e ^> Calculated by ffl,

Where _TO constitute D _k is defined as d _m = {d _mn = _{amn +} jb _mn : _n = i ~ wi}, where Α ^(Λί ) is the positive frequency signal, Α ^(Λί ) is the negative frequency signal Μ means the conversion level in the discrete group determined by the strength of the received signal, and Ν is the discrete Fourier transform. Data transmission device characterized in that the size for the ring.

[Claim 4]

A method of transmitting data in a high Doppler frequency fading environment in a wireless communication system supporting an orthogonal frequency division multiple access scheme,

Outputting a raw spread symbol by converting a raw symbol generated by a predetermined modulation scheme into a discrete group;

Constructing a frame based on a raw spread symbol matrix in a predetermined subcarrier by inputting the outputted raw spread symbol high five sequences;

Generating a transmission symbol matrix on the predetermined subcarrier through encoding of the raw spread symbol matrix of the configured frame; And

Mapping the generated transmission symbol matrix to the predetermined subcarrier and converting the transmitted symbol matrix to an inverse high-speed bund to transmit the plurality of antennas through a plurality of antennas;

[Claim 5]

The method of claim 4, wherein the outputting of the raw spread symbol comprises:

The raw symbol ^{D =} { ^d G ' ^d i'"" ^d M} * generated by the predetermined modulation method

_ N

F = '= ^ _Mi + ^^ = i ~, the raw spread symbol ^S lk _^ On of

Calculate the solution,

Where ^ ⁼ Κ · « ^{= α} ™ ⁺ ^ H- ¹ }, where β _ρΜ is a positive frequency signal, is a negative frequency signal, and Μ depends on the strength of the received signal. The discrete Fourier transform level is determined, and Ν is a size for the Discrete Fourier transform.

[Claim 6]

The raw symbol ^D * ⁼ { ^dQ ' ^d i''"' ^d M generated by the predetermined modulation scheme as an input = ^ ₊ 5„ = ⁾ = ⁾ ₊ ^ (ratio, / = 1 M ^{) the} raw spread symbol being defined

、

A ^(M)

-I

Calculated by

Where ^ ^ constituting * is defined as ^ ⁼ Κ · _" ^{= α} _™ ⁺ „ ^: "= ι ^~ ^ -ι ^} ,

Is the negative frequency signal, Μ is the conversion level in the discrete group determined by the strength of the received signal, and Ν is the variation in the discrete group. Data transmission method characterized in that the size for the exchange

[Claim 7]

An apparatus for receiving data in a high Doppler frequency fading environment in a wireless communication system supporting an orthogonal frequency division multiple access scheme,

Differential space-time decoding for outputting a raw spread symbol matrix through differential space-time decoding on the received signal with input signals received from a predetermined subcarrier after the Fourier transform and channel prediction values and self-generated raw spread symbols. group;

A frame separator for separating S raw spread symbols and S sequences from a raw spread symbol matrix output by the differential space-time encoding;

A channel predictor for predicting a channel state by five sequences separated by the frame separator and providing a channel prediction value to the differential space-time decoder;

An adaptive inverse discrete Fourier transformer for converting the raw spread symbols separated by the frame separator into inverse discrete clusters and outputting the raw symbols;

And an adaptive discrete Fourier transformer for providing the differential spatiotemporal decoder with a raw spread symbol generated by discrete Fourier transforming of the received data obtained through signal determination on a raw symbol output from a transformer in the adaptive inverse discrete group. Receiver.

[Claim 8] The method of claim 7,

The differential space-time decoder outputs a raw spread symbol matrix by s _ _w ^ _r ,

Where * is the first received symbol matrix in the th subcarrier, is the predicted channel gain, and () "is defined as the hermit.

9. The data receiving apparatus according to claim 7, further comprising a summer for summing and outputting a raw spread symbol output from a frame separator corresponding to each of the plurality of antennas when the plurality of receiving antennas are provided.

10. The data receiving apparatus of claim 7, wherein the channel estimator predicts a channel state by using a linear internal sampling method in a symbol section existing between the training sequences.

[Claim 11]

The channel estimator of claim 13, wherein the channel estimator

And a data receiver for predicting a solution channel condition.

[Claim 12]

A method for receiving data in a high Doppler frequency fading environment in a wireless communication system supporting an orthogonal frequency division multiple access scheme,

Outputting a raw spread symbol matrix by performing differential space-time decoding on the received signal by receiving a received signal received from a predetermined subcarrier and a channel prediction value and a self-generated raw spread symbol after the transform is performed on a group;

Separating the raw spread symbol and the sequence from the outputted raw spread symbol matrix;

Generating a channel prediction value by predicting a channel state by the separated training sequence;

Outputting a raw symbol by converting the separated raw spread symbol into an inverse discrete group; And generating the original raw spread symbol by discrete Fourier transforming the received data obtained through the signal determination on the outputted raw symbol.

13. The process of claim 12, wherein the outputting of the raw spread symbol matforces comprises inputting the received signal, the channel prediction value, and the self-generated raw spread symbol as inputs.

Outputs a trix, where ^R «is the ^ th received symbol matrix at the th subcarrier, h _lk _ _w is the predicted channel gain, and (is defined as the hermitage

[Claim 14] The method according to claim 12, wherein when a plurality of reception antennas are provided, the raw spread symbols outputted by the high-precision dividing corresponding to each of the plurality of antennas are added to the inverse discrete group. A data receiving method further comprising the step of outputting for conversion.

15. The data receiving method of claim 12, wherein the generating of the channel prediction value comprises predicting a channel state using a linear interpolation method in a symbol interval existing between the training sequences.

[16] The method of claim 17, wherein the process of generating the channel prediction value

Channel status by K ^^^^^ o ^^ fN-i ^ k ^ r) ^

Data reception method characterized by prediction.

[Claim 17] In the scheduling method for allocating resources in a multiple security system or system supporting multiple users, the signal-to-noise ratio is assumed when the frequency characteristics of the subchannels allocated to the maximum ratio combined terminals are the same. Arranging the sub-channels in ascending order from the sub-channels of the terminal with a small inverse number; And a service in the case of a real-time service according to the order based on the arrangement. Allocating a minimum power satisfying the quality, and in the case of the non-real-time service, the step of sequentially allocating power to all the terminals in consideration of the distance to the terminal.