JP3499768B2 - Waveform equalizer, mobile radio apparatus using the same, base station radio apparatus, and mobile communication system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waveform equalizer having good equalization performance even when the propagation path varies greatly, and a mobile phone using the waveform equalizer to remove the effect of frequency selective fading. The present invention relates to a mobile wireless device such as a telephone, a car phone, a self-employed digital wireless communication telephone, a base station device, and a mobile communication system including the mobile wireless device and the base station device.

[0002]

2. Description of the Related Art A conventional waveform equalizer will be described with reference to FIG.

In FIG. 11, an A / D converter 110 is provided.
1 samples analog reception data and converts it into digital data series data. This A / D converter 1
The digital data series data converted in 101 is stored in the reception data buffer 1102 for the equalization processing unit.

The forward equalizer 1100A is a waveform equalizer that performs equalization in the order of reception time series, and is a filter unit 110.
3, a determination unit 1104, a switch (SW) 1105, an error calculation unit 1106, and a tap coefficient update unit 1107. The equalization output buffer 1108 stores the equalization output of the forward equalizer 1000, and the equalization error buffer 1109 stores the equalization error for each equalization step in the forward equalization. is there.

The backward equalizer 1100B is a waveform equalizer that performs equalization in the reverse order of the time series of reception, and the filter unit 11
11, a determination unit 1112, a switch (SW) 1113, an error calculation unit 1114, and a tap coefficient update unit 1115. Further, the reception data time series inverter 1110 performs a pre-processing for reverse equalization, which inverts the time series of reception data. The equalization output buffer 1116 stores the equalization output of the backward equalizer 1100, and the equalization error buffer 1117 stores the equalization error at each equalization step in the backward equalization.

Equalization error comparator 1118 compares the equalization error for forward equalization stored in equalization error buffer 1109 with the equalization error for backward equalization stored in equalization error buffer 1117. Then, the equalization direction selection information is output. The equalization output selection switch (SW) 1119 is used for the equalization error comparator 1
Based on the equalization direction selection information from 118, either the equalization output by the equalization output buffer 1108 by the forward equalization or the equalization output by the equalization output buffer 1116 by the backward equalization is selected, and the final It is output as an equalized output. Further, the equalization output time series inverter 1120 inverts the time series of the data of the equalization output buffer 1116, and returns the equalization output of the backward equalizer 1100 in the order of reception time series, after the backward equalization. The processing is performed.

Next, the operation of the conventional waveform equalizer will be described with reference to FIGS. 11 and 2.

FIG. 2 shows the received data at time T201.
From the time T202 to the time T202, the data received from the time T202 to the time T203 is a data series, and the data received from the time T203 to the time T204 is a training series 2.

The received analog reception data is A /
It is sampled by the D converter 1101 and converted into a digital data series. Then, the converted digital data series is stored in the reception buffer 1102 for an equalization processing unit, that is, for one burst shown in FIG.

In the forward equalization training period, FIG.
The training sequence 1 shown in is input to the filter unit 1103 in the order of reception time series. That is, the received data is sequentially input from time T201 to time T202. The received data corresponding to this is taken out from the received data buffer 1102 and input to the filter section 1103. Waveform equalization is performed in the filter unit 1103,
The soft decision information is output as the equalization output of the forward equalization.

During this training period, the switch 110
Since 5 is connected to the contact A side, the training information is returned to the filter unit 1103. Further, the training information and the soft decision information from the filter unit 1103 are input to the error calculation unit 1106, and the equalization error is calculated. The calculated equalization error and the tap coefficient of the filter unit 1103 are input to the tap coefficient updating unit 1107, and a new tap coefficient that reduces the equalization error is calculated.
The calculated tap coefficient is set as a new tap coefficient of the filter unit 1103. This forward equalization training is performed by repeating the above-described operation.

In the tracking period of the forward equalization, as shown in FIG.
The data sequence shown in is input to the filter unit 1103 in the order of time of reception. That is, from time T202 to time T20
Received data is sequentially input in the direction of 3. The received data corresponding to this is the received data buffer 1
It is taken out from 102 and inputted into the filter section 1103. The filter unit 1103 performs waveform equalization, and outputs soft decision information as an equalization output for forward equalization. The soft decision information output from the filter unit 1103 is the decision unit 110.
4 and the signal point of the symbol is determined.

During this tracking period, the switch 110
Since 5 is connected to the contact B side, the determined result is returned to the filter unit 1103. The determined result is stored in the equalized output buffer 1108. Further, the result of the determination and the soft decision information from the filter unit 1103 are input to the error calculation unit 1106, and the equalization error is calculated. The calculated equalization error and the tap coefficient of the filter unit 1103 are input to the tap coefficient updating unit 1107, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is used as the filter unit 1103.
Is set as the new tap coefficient of. The equalization error for each equalization step of forward equalization, which is the output of the error calculation unit 1106, is stored in the equalization error buffer 1109. The tracking of the forward equalization is performed by repeating the above operation.

In the backward equalization training period, FIG.
The training sequence 2 shown in is input to the filter unit 1111 in the reverse order of the reception time sequence. That is, the received data is sequentially input in the direction from time T204 to time T203. The received data corresponding to this is taken out from the received data buffer 1102 and input to the filter section 1111 through the received data time series inverter 1110. The filter unit 1111 performs waveform equalization, and outputs soft decision information as an equalization output for backward equalization.

During this training period, the switch 111
Since 3 is connected to the contact A side, the training information is returned to the filter unit 1111. Further, the training information and the soft decision information from the filter unit 1111 are input to the error calculation unit 1114 and the equalization error is calculated. The calculated equalization error and the tap coefficient of the filter unit 1111 are input to the tap coefficient updating unit 1115, and a new tap coefficient that reduces the equalization error is calculated.
The calculated tap coefficient is set as a new tap coefficient of the filter unit 1111. This backward equalization training is performed by repeating the above-described operation.

In the tracking period of the backward equalization, as shown in FIG.
The data sequence shown in is input to the filter unit 1111 in the reverse order of the reception time sequence. That is, from time T203 to time T
Received data is sequentially input in the direction of 202. The received data corresponding to this is taken out from the received data buffer 1102 and received data time series inverter 11
It is input to the filter unit 1111 through 10. The filter unit 1111 performs waveform equalization, and outputs soft decision information as an equalization output for backward equalization. Filter unit 111
The soft decision information output from 1 is input to decision section 1112, and the signal points of the symbols are decided.

During this tracking period, the switch 111
Since 3 is connected to the contact B side, the determined result is fed back to the filter unit 1111. The determined result is stored in the equalized output buffer 1116. Further, the determination result and the soft decision information from the filter unit 1111 are input to the error calculation unit 1114, and the equalization error is calculated. The calculated equalization error and the tap coefficient of the filter unit 1111 are input to the tap coefficient updating unit 1115, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is used in the filter unit 1111.
Is set as the new tap coefficient of. The equalization error for each equalization step of the backward equalization, which is the output of the error calculation unit 1114, is stored in the equalization error buffer 1117. This reverse equalization tracking is performed by repeating the above-described operation.

After the above-described processing of the forward equalization and the backward equalization is completed, either the equalization output by the forward equalization or the equalization output by the backward equalization is selected.

That is, the equalization error comparator 1118 includes
The equalization error due to the forward equalization from the equalization error buffer 1109 and the equalization error due to the backward equalization from the equalization error buffer 1117 are input. Equalization error comparator 1118
Then, some calculation is performed on these equalization errors, and equalization direction selection information for selecting an equalization direction with a small equalization error is output.

This equalization direction selection information is input to the equalization output selection switch 1119, and if forward equalization is specified in the equalization error selection information, the equalization output selection switch 1119.
Is set to the contact A side, the equalized output by the forward equalization is taken out from the equalized output buffer 1108, and this becomes the final equalized output. If backward equalization is designated in the equalization error selection information, the equalization output selection switch 1119 is selected.
Is set to the contact B side, and the equalized output by the backward equalization from the equalized output buffer 1116 is equalized output time series inverter 11
It is taken out through 20 and this becomes the final equalized output.

[0021]

The conventional waveform equalizer as described above compares the equalization errors of the forward equalization and the backward equalization, and outputs only the equalization output in the direction with the least equalization error. Is configured to be adopted. This method is effective when there is almost no fluctuation in the propagation path within a burst that is a unit of equalization processing. Further, since the training for the forward equalization and the training for the backward equalization are performed twice, the equalization characteristic does not deteriorate if only one of the training results is good. It is effective when the propagation path before operating cannot be accurately estimated.

However, in the case where there is a large variation in the propagation path within a burst, which is a unit of equalization processing, the equalization characteristics at the back of the burst are deteriorated by the forward equalization, and the backward equalization is performed. Then, the equalization characteristics before the burst tend to deteriorate. As a result, good characteristics cannot be obtained regardless of which equalization direction is selected.

In addition, it is a calculation that only one of the equalization processing units is selected, even though the waveform equalization is performed twice, that is, the forward equalization and the backward equalization for one equalization processing unit. There is a problem that the processing is wasted.

The present invention solves such a problem, and it is possible to obtain good equalization performance not only when there is almost no fluctuation in the propagation path within a burst, but also when there is significant fluctuation in the propagation path. An object of the present invention is to provide a waveform equalizer, a mobile wireless device using the same, a base station wireless device, and a mobile communication system.

[0025]

In order to solve the above-mentioned problems, the present invention provides a waveform equalizer and a mobile radio device, base station radio device and mobile communication system using the same.
The waveform equalizer includes a forward equalizer that equalizes waveforms in the order of reception of received data, a backward equalizer that equalizes waveforms in the reverse order of reception of received data, and the forward equalizer. Add the soft decision information that is the equalization result of the forward equalization of the equalizer and the soft decision information after time series inversion of the soft decision information that is the equalization result of the backward equalization of the backward equalizer And an deciding means for obtaining an equalized output by deciding the addition result by the adding means.

As a result, there are two types of forward equalization and backward equalization.
Final softening output is obtained by synthesizing the respective soft decision information obtained from the waveform equalization of times by paying attention to the reception level and the equalization error, and deciding the synthesized result.

Therefore, according to the present invention, good equalization performance can be obtained not only when there is almost no fluctuation in the propagation path within the burst, but also when there is significant fluctuation in the propagation path.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A waveform equalizer according to claim 1 of the present invention comprises a forward equalizer for equalizing waveforms in a time series of reception of received data and a reverse order of time series of reception of received data. A backward equalizer for waveform equalization, a soft decision information that is the equalization result of the forward equalization of the forward equalizer, and an equalization result of the backward equalization of the backward equalizer. Addition means for adding soft decision information after time-series inversion of soft decision information, and decision means for obtaining an equalized output by judging the addition result by the addition means, and forward equalization A diversity effect is obtained by adding and synthesizing the results of two operations of backward equalization, and there is an effect that waveform equalization can be performed with good performance even when the propagation path varies greatly within a burst.

A waveform equalizer according to claim 2 of the present invention is
A forward equalizer that equalizes waveforms in order of reception time series of received data, a backward equalizer that equalizes waveforms in reverse order of reception time series of received data, and a training period data of the received data A reception level detecting means for detecting a reception level during a training period for forward equalization and a reception level during a training period for backward equalization, and a soft decision which is the equalization result for the forward equalization of the forward equalizer. First multiplication means for multiplying information by the reception level in the forward equalization training period, and soft after time series inversion of soft decision information which is the equalization result of the backward equalizer of the backward equalizer Second multiplication means for multiplying the determination information by the reception level in the backward equalization training period, an addition means for adding the multiplication results of the first and second multiplication means, and a determination of the addition result by the addition means. By It is provided with a determination means to obtain the output of the equalization, utilizing the fact that the higher the reception level during the training period, the better the equalization performance, the soft decision information in each direction is weighted and combined, By determining the result, there is an effect that waveform equalization can be performed with good performance even when the propagation path changes drastically within the burst.

A waveform equalizer according to claim 3 of the present invention is
Forward equalizer for equalizing waveforms in the order of reception of received data, backward equalizer for equalizing waveforms in reverse order of reception of received data, forward equalizer of the forward equalizer, etc. From the equalization error at each equalization step by equalization, weighting is determined for the soft decision information that is the equalization result of the forward equalization of the forward equalizer, and the backward equalizer of the backward equalizer is equalized. Weighting calculation means for determining weighting for soft decision information which is the equalization result of the backward equalization of the backward equalizer from the equalization error at each equalization step by equalization, and the forward equalization First multiplication means for multiplying the soft decision information which is the equalization result by the weighting determined by the weighting calculation means, and the soft decision information after time series inversion of the soft decision information which is the equalization result of the backward equalization. And the weighting determined by the weighting calculation means are multiplied. The equalization performance is provided with two multiplication means, addition means for adding the multiplication results of the first and second multiplication means, and determination means for obtaining an equalized output by determining the addition result by the addition means. Focusing on the equalization error, which is also an index of, and by weighting and combining the soft decision information in each direction by the weighting calculated from this equalization error,
A greater diversity effect can be obtained, and by determining the synthesis result, there is an effect that waveform equalization can be performed with good performance even when there is a large fluctuation in the propagation path within the burst.

In the invention according to claim 4 of the present invention, the weighting calculation means assigns the weight to the soft decision information by the forward equalization for each equalization step to the forward equalization for each equalization step. Determined by the reciprocal of the equalization error, and weighting the soft decision information by the backward equalization for each equalization step is determined by the reciprocal of the equalization error by the backward equalization for each equalization step, By weighting the reciprocal of the equalization error for each equalization step as it is, there is an effect that it is possible to provide a waveform equalizer with a small amount of calculation and good performance.

In the invention according to claim 5 of the present invention, the weighting calculation means assigns the weight to the soft decision information by the forward equalization for each equalization step to the number before and after each equalization step by the forward equalization. Determined by the reciprocal of the sum of equalization errors for symbols,
And the weighting to the soft decision information by the backward equalization at each equalization step is determined by the reciprocal of the sum of the equalization errors for several symbols before and after each equalization step by the backward equalization. Not only the equalization error in the equalization step,
The weighting can be determined by taking into account the equalization errors before and after that as well, and this makes it possible to avoid erroneous determinations in the waveform equalizer due to a drop in the reception level for a short time, and to provide a good waveform equalizer. Is provided.

In the invention according to claim 6 of the present invention, the weighting calculation means introduces a forgetting factor λ (0 ≦ λ ≦ 1) for each equalizing step of forward equalization, and an equalizing error with a forgetting factor. And the weighting to the soft decision information by the forward equalization for each equalization step is determined by the reciprocal of the equalization error with the forgetting factor for each equalization step by the forward equalization, and the backward direction etc. An equalization error with a forgetting factor, which introduces a forgetting factor λ (0 ≦ λ ≦ 1), is calculated for each equalization step, and the soft decision information is weighted by the backward equalization for each equalization step. It is determined by the reciprocal of the equalization error with the forgetting coefficient at each equalization step by the backward equalization, and when the forgetting coefficient λ is introduced to the equalization error, the reception C / N becomes small. The effect of thermal noise is reduced, and it is possible to provide a waveform equalizer with good performance. Have an effect.

According to a seventh aspect of the present invention, the weighting calculation means comprises a C / N estimation means, and the C / N estimation means uses the received data, equalization error, etc. to estimate the C / N estimated value. Is calculated and the forgetting factor λ is set according to the C / N estimated value. Instead of adopting a constant forgetting factor, when the reception quality is good, a small forgetting factor is used to enter the propagation path. Has the effect that the following speed can be improved, the effect of thermal noise can be reduced by using a large forgetting factor when the reception quality is poor, and the performance of the waveform equalizer can be further improved.

The invention according to claim 8 of the present invention is a mobile radio apparatus comprising a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is a time series of reception of received data. It is a forward equalizer that sequentially equalizes waveforms, a backward equalizer that equalizes waveforms in reverse order of reception time series of reception data, and an equalization result of forward equalization of the forward equalizer. Addition means for adding soft decision information and soft decision information after time series inversion of the soft decision information, which is the equalization result of the backward equalization of the backward equalizer, and the addition result by the adding means is determined By providing a determination means for obtaining an equalized output by adding the two operation results of the forward equalization and the backward equalization, and combining them to obtain a diversity effect and to propagate in the burst. Performs waveform equalization with good performance even when the road changes significantly Preparative because it is possible, has the effect of mobile communication system, the transmission rate of the large zone system can provide good terminal reception performance be used in an environment where a high-speed mobile communication system like the effect of multipath fading can not be ignored.

According to a ninth aspect of the present invention, there is provided a mobile radio apparatus including a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is a time series of reception of received data. Forward equalizer for sequentially performing waveform equalization, backward equalizer for performing waveform equalization in reverse order of reception time series of reception data, and training for forward equalization based on data in the training period of the reception data Reception level detecting means for detecting a reception level of a period and a reception level of a training period of backward equalization, soft decision information as the equalization result of the forward equalization of the forward equalizer, and the forward equalization A first multiplication means for multiplying the reception levels during the training period of
Second multiplication means for multiplying the soft decision information after time series inversion of the soft decision information, which is the equalization result of the backward equalization of the backward equalizer, by the reception level of the training period of the backward equalization, And an addition unit that adds the multiplication results of the first and second multiplication units and a determination unit that obtains an equalized output by determining the addition result of the addition unit.
Taking advantage of the fact that the higher the reception level during the training period, the better the equalization performance is, the soft decision information in each direction is weighted and combined, and the result is decided to determine the propagation path within the burst. It is possible to perform waveform equalization with good performance even when there is a large fluctuation, so even if a large-zone mobile communication system or a mobile communication system with a high transmission rate is used in an environment where the effects of multipath fading cannot be ignored. This has the effect of providing a terminal with good performance.

A tenth aspect of the present invention is a mobile radio apparatus comprising a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is a time series of reception of received data. A forward equalizer that sequentially equalizes the waveform,
A backward equalizer that equalizes the waveforms in the reverse order of the time series of reception of the received data, and an equalization error of each equalization step due to the forward equalization of the forward equalizer from the forward equalizer The weighting is determined for the soft decision information that is the equalization result of the forward equalization, and from the equalization error at each equalization step due to the backward equalization of the backward equalizer, the backward equalizer is Weighting calculation means for deciding weighting on soft decision information which is equalization result of backward equalization, soft decision information which is equalization result of forward equalization and weighting decided by the weighting calculation means First multiplying means for matching, second multiplying means for multiplying the soft decision information after time series inversion of the soft decision information as the equalization result of the backward equalization and the weighting determined by the weighting calculation means, Adds the multiplication results of the first and second multiplication means And an deciding means for obtaining an equalized output by deciding the addition result by the adding means, and the soft decision information in each direction is weighted and combined by weighting calculated from the equalization error. so,
Greater diversity effects can be obtained, and waveform equalization can be performed with good performance even when the propagation path changes drastically within a burst.Therefore, large-zone mobile communication systems and mobile communication systems with high transmission speeds can be used. This has the effect of providing a terminal with good reception performance even when used in an environment where the effects of multipath fading cannot be ignored.

[0038] An eleventh aspect of the present invention is a base station radio apparatus including a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is used when receiving received data. A forward equalizer for waveform equalization in sequence order, a backward equalizer for waveform equalization in reverse order of reception time series of reception data, and an equalization result of forward equalization of the forward equalizer. Adding means for adding a certain soft decision information and soft decision information after time series inversion of the soft decision information which is the equalization result of the backward equalization of the backward equalizer, and the addition result by the adding means A determination means for obtaining an equalized output by making a determination is provided, and a diversity effect is obtained by adding the two operation results of the forward equalization and the backward equalization and combining them, and Performs waveform equalization with good performance even when the propagation path changes drastically Therefore, it is possible to provide a base station wireless device having good reception performance even when a large-zone mobile communication system or a mobile communication system having a high transmission rate is used in an environment in which the influence of multipath fading cannot be ignored. Have.

According to a twelfth aspect of the present invention, there is provided a base station radio apparatus including a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is used when receiving received data. Forward equalizer for waveform equalization in sequence order, backward equalizer for waveform equalization in reverse order of reception time series of reception data, and forward equalization based on the data in the training period of the reception data. Reception level detecting means for detecting a reception level during a training period and a reception level during a backward equalization training period, soft decision information as the equalization result of the forward equalization of the forward equalizer, and the forward direction etc. First multiplication means for multiplying the reception level of the equalization training period, and soft decision information and reverse direction after time-series inversion of the soft decision information which is the equalization result of the reverse equalization of the reverse equalizer. Training period The multiplying the reception level 2
The present invention is provided with a multiplication means, an addition means for adding the multiplication results of the first and second multiplication means, and a determination means for obtaining an equalized output by determining the addition result by the addition means. Utilizing the fact that equalization performance tends to improve as the reception level increases, the soft-decision information in each direction is weighted and combined, and the result is judged. Even if it is possible to perform waveform equalization with good performance, a base with good reception performance even if a large-zone mobile communication system or a mobile communication system with a high transmission rate is used in an environment in which the effects of multipath fading cannot be ignored. This has the effect of providing a station wireless device.

A thirteenth aspect of the present invention is a base station radio apparatus including a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is used when receiving received data. Forward equalizer for waveform equalization in sequence order, backward equalizer for waveform equalization in reverse order of time series of reception of received data, and each equalization step by forward equalization of the forward equalizer Each equalization step by determining the weighting for the soft decision information which is the equalization result of the forward equalization of the forward equalizer from each equalization error and by the backward equalization of the backward equalizer Weighting calculation means for determining weighting for the soft decision information which is the equalization result of the backward equalization of the backward equalizer from each equalization error, and the soft equalization result of the forward equalization. Multiply the judgment information and the weight determined by the weight calculation means. A second multiplication means for multiplying the soft decision information after time-sequential inversion of the soft decision information, which is the equalization result of the backward equalization, and the weighting determined by the weighting calculation means; It is provided with an adding means for adding the multiplication results of the first and second multiplying means, and a judging means for obtaining an equalized output by judging the addition result by the adding means, and each is weighted by an equalization error. By weighting and synthesizing soft decision information in the direction, a larger diversity effect can be obtained, and waveform equalization can be performed with good performance even when the propagation path fluctuation is large within a burst. Even if a mobile communication system or a mobile communication system with a high transmission speed is used in an environment where the influence of multipath fading cannot be ignored, it is possible to provide a base station wireless device with good reception performance. It has the effect of.

The invention according to claim 14 of the present invention comprises a base station and a mobile station, and at least one of the base station and the mobile station is provided with a waveform equalizer for removing the influence of frequency selective fading. In the system, the waveform equalizer includes a forward equalizer that equalizes waveforms in a time series of reception of received data, and a backward equalizer that equalizes waveforms in a reverse order of time series of reception of received data. And, after time series inversion of the soft decision information that is the equalization result of the forward equalization of the forward equalizer and the equalization result of the backward equalization of the backward equalizer. An addition means for adding the soft decision information and a decision means for obtaining an equalized output by judging the addition result by the addition means are provided, and the calculation result of two times of forward equalization and backward equalization is provided. Diversity effect is obtained by adding and combining Is, such an action because it is possible to perform the performance good waveform equalization even when the variation of the transfer path in the burst intense, strong multipath fading, can provide a high-quality mobile communication system.

The invention according to claim 15 of the present invention comprises a base station and a mobile station, and at least one of the base station and the mobile station is provided with a waveform equalizer for removing the influence of frequency selective fading. In the system, the waveform equalizer includes a forward equalizer that equalizes waveforms in a time series of reception of received data, and a backward equalizer that equalizes waveforms in a reverse order of time series of reception of received data. A reception level detecting means for detecting a reception level during a training period for forward equalization and a reception level during a training period for backward equalization based on data during a training period for the received data; The first equalizing means for multiplying the soft-decision information, which is the equalization result of the forward equalization, and the reception level of the training period of the forward equalization; and the equalization result of the backward equalization of the backward equalizer. Some soft judgment Second multiplying means for multiplying the soft decision information after time series inversion of the information and the reception level in the training period for backward equalization; and adding means for adding the multiplication results of the first and second multiplying means, It is provided with a determination means for obtaining an equalized output by determining the addition result by the addition means, and utilizing that the equalization performance tends to improve as the reception level during the training period increases,
By synthesizing the weighted soft decision information in each direction, and by deciding the result, waveform equalization can be performed with good performance even when there is a large fluctuation in the propagation path within the burst.
It has the effect of providing a high-quality mobile communication system that is resistant to multipath fading.

The invention according to claim 16 of the present invention comprises a base station and a mobile station, and at least one of the base station and the mobile station is provided with a waveform equalizer for removing the influence of frequency selective fading. In the system, the waveform equalizer includes a forward equalizer that equalizes waveforms in a time series of reception of received data, and a backward equalizer that equalizes waveforms in a reverse order of time series of reception of received data. And the weighting is determined for the soft decision information which is the equalization result of the forward equalization of the forward equalizer from the equalization error at each equalization step due to the forward equalization of the forward equalizer. In addition, the weighting is determined for the soft decision information which is the equalization result of the backward equalization of the backward equalizer from the equalization error at each equalization step due to the backward equalization of the backward equalizer. Weighting calculation means and the equalization result of the forward equalization First multiplication means for multiplying a certain soft decision information by the weight determined by the weight calculation means, soft decision information after time series inversion of the soft decision information which is the equalization result of the backward equalization, and the weight calculation Second multiplication means for multiplying the weightings determined by the means, and addition means for adding the multiplication results of the first and second multiplication means,
The addition means is provided with a determination means for obtaining an equalized output by determining the addition result by the addition means. By weighting and synthesizing soft decision information in each direction by weighting calculated from the equalization error, a greater diversity is obtained. Since the effect can be obtained and the waveform equalization can be performed with good performance even when the propagation path changes drastically within the burst, there is an effect that it is possible to provide a high quality mobile communication system that is resistant to multipath fading.

(Embodiment 1) Embodiment 1 of the present invention will be described with reference to FIGS. 1, 2 and 3.

FIG. 1 is a block diagram showing the configuration of the waveform equalizer according to the first embodiment of the present invention. It should be noted that this FIG.
The waveform equalizer shown in (1) is a decision feedback type equalizer, and a waveform equalizer of any configuration such as a linear equalizer or a lattice type equalizer can be used.

In FIG. 1, the waveform equalizer is a forward equalizer 100A, a backward equalizer 100B, and an A / D converter 10.
1, received data buffer 102, soft decision information buffer 1
08, received data time series inverter 109, soft decision information buffer 115, soft decision information time series inverter 116, adder 1
17, a judging device 118 is provided.

The A / D converter 101 samples analog reception data and converts it into a digital data series. The digital data series converted by the A / D converter 101 is equal to the equalization processing unit in the reception data buffer 10
It is configured to be stored in 2.

The forward equalizer 100A is a waveform equalizer that performs equalization in order of reception time series, and includes a filter unit 103, a determination unit 104, a switch (SW) 105, and an error calculation unit 10.
6 and a tap coefficient updating unit 107. The soft decision information buffer 108 stores the equalized output of the forward equalizer 100A.

The backward equalizer 100B is a waveform equalizer for performing equalization in the reverse order of reception time series, and includes a filter section 110, a determination section 111, a switch (SW) 112, an error calculation section 113, and It is composed of the tap coefficient updating unit 114. The received data time series inverter 109 inverts the time series of the received data, and performs pre-processing for backward equalization. The soft decision information buffer 115 stores the soft decision information which is the equalized output of the backward equalizer 100B. The soft-decision information time-series inverter 116 inverts the time-series of the data of the soft-decision information buffer 115 and returns the soft-decision information, which is the equalized output of the backward equalizer 100B, in the order of reception time series. Perform post-equalization processing.

The adder 117 receives the soft decision information obtained by the forward equalization of the forward equalizer 100A and the soft decision information obtained by the backward equalization of the backward equalizer 100B. to add. The determiner 118 is the adder 11
The result of addition in 7 is determined to obtain the final equalized output. In this way, the bidirectional equalizer is configured by combining the results of the forward equalization and the backward equalization.

FIG. 2 shows the received data at time T201.
From the time T202 to the time T202 is the training sequence 1, the data received from the time T202 to the time T203 is a data sequence, and the data received from the time T203 to the time T204 is a burst of the training sequence 2.

FIG. 3 is a diagram showing contents of each buffer and addition contents of the adder when the data series of FIG. 2 has information for n symbols. In FIG. 3, (a)
Shows the contents of the soft decision information buffer 108, (b) shows the contents of the soft decision information buffer 115, and (c) shows the contents of the output data of the adder 117.

Next, the operation of the waveform equalizer according to the first embodiment of the present invention will be described with reference to FIGS. 1, 2 and 3.

First, the received analog reception data is sampled by the A / D converter 101 and converted into a digital data series. Then, the converted digital data series is stored in the reception data buffer 102 for an equalization processing unit, that is, for one burst shown in FIG.

In the forward equalization training period, FIG.
The training sequence 1 shown in is input to the filter unit 103 in the order of time of reception. That is, the received data is sequentially input from time T201 to time T202. The received data corresponding to this is taken out from the received data buffer 102 and input to the filter unit 103. The filter unit 103 performs waveform equalization, and outputs soft decision information as an equalization output for forward equalization.

During this training period, the switch 10
Since 5 is connected to the contact A side, the training information is returned to the filter unit 103. Further, the training information and the soft decision information from the filter unit 103 are input to the error calculation unit 106, and the equalization error is calculated. And
The calculated equalization error and the tap coefficient of the filter unit 103 are input to the tap coefficient updating unit 107, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 103. This forward equalization training is performed by repeating the above-described operation.

In the tracking period of the forward equalization, as shown in FIG.
The data sequence shown in is input to the filter unit 103 in the order of time of reception. That is, from time T202 to time T203
Received data is sequentially input in the direction of.
The received data corresponding to this is the received data buffer 102.
And is input to the filter unit 103. The filter unit 103 performs waveform equalization, and outputs soft decision information as an equalization output for forward equalization. Filter unit 103
The soft decision information output from the soft decision information buffer 108
Are stored in the order of reception time series. In addition, the filter unit 10
The soft decision information output from No. 3 is input to decision section 104, and the signal points of the symbols are decided.

In this tracking period, the switch 10
Since No. 5 is connected to the contact B side, the determined result is returned to the filter unit 103. Further, the determination result and the soft decision information from the filter unit 103 are the error calculation unit 1
It is input to 06 and the equalization error is calculated. The calculated equalization error and the tap coefficient of the filter unit 103 are input to the tap coefficient updating unit 107, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 103. The tracking of the forward equalization is performed by repeating the above operation. Here, when the data sequence has n symbols, the content of the soft decision information buffer 108 becomes as shown in FIG. 3A at the end of the tracking of the forward equalization.

In the backward equalization training period, FIG.
The training sequence 2 shown in is input to the filter unit 110 in the reverse order of the reception time sequence. That is, the received data is sequentially input in the direction from time T204 to time T203. The received data corresponding to this is taken out from the received data buffer 102 and input to the filter section 110 through the received data time series inverter 109. The filter unit 110 performs waveform equalization, and outputs soft decision information as an equalization output for backward equalization.

During this training period, the switch 11
Since No. 2 is connected to the contact A side, the training information is returned to the filter unit 110. Further, the training information and the soft decision information from the filter unit 110 are input to the error calculation unit 113, and the equalization error is calculated. And
The calculated equalization error and the tap coefficient of the filter unit 110 are input to the tap coefficient updating unit 114, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 110. This backward equalization training is performed by repeating the above-described operation.

In the backward equalization tracking period, as shown in FIG.
The data series shown in is input to the filter unit 110 in the reverse order of the time series of reception. That is, from time T203 to time T2
The received data will be sequentially input in the 02 direction. The received data corresponding to this is the received data buffer 1
02, and is input to the filter unit 110 through the received data time series inverter 109. Filter unit 11
At 0, waveform equalization is performed, and soft decision information is output as an equalization output for backward equalization. The soft decision information output from the filter unit 110 is stored in the soft decision information buffer 115 in the reverse order of the reception time series. Further, the soft decision information output from the filter unit 110 is input to the decision unit 111, and the signal point of the symbol is decided.

In this tracking period, the switch 11
Since No. 2 is connected to the contact B side, the determined result is returned to the filter unit 110. Further, the determination result and the soft decision information from the filter unit 110 are the error calculation unit 1
It is input to 13, and the equalization error is calculated. The calculated equalization error and the tap coefficient of the filter unit 110 are input to the tap coefficient updating unit 114, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 110. This reverse equalization tracking is performed by repeating the above-described operation. Here, when the data sequence has n symbols, the content of the soft decision information buffer 115 becomes as shown in FIG. 3B at the end of the tracking of the backward equalization.

After the processing of the forward equalization and the backward equalization is completed, the soft decision information by the forward equalization and the soft decision information by the backward equalization are combined. At this time, the soft decision information buffer 108 stores the soft decision information shown in FIG. 3A, and the soft decision information buffer 115 stores the soft decision information shown in FIG. 3B. At the time of the combination, soft decision information corresponding to the reception time is combined.

That is, the soft decision information by the backward equalization is taken out from the soft decision information buffer 115 and inputted to the adder 117 through the soft decision information time series inverter 116. The soft decision information obtained by the forward equalization is taken out from the soft decision information buffer 108 and input to the adder 117 as it is. The adder 117 adds the soft decision information by the forward equalization and the soft decision information by the backward equalization, and the addition result is input to the decision unit 118. Here, when the data sequence has n symbols, the addition result input to the determiner 118 is as shown in FIG. The determiner 118 determines the signal points of the symbols and obtains the final equalization result, the equalized output.

According to the first embodiment of the present invention as described above, the final equalized output is not obtained by selecting the forward equalization and the backward equalization as in the conventional technique, but the forward equalization is obtained. Since the soft decision information, which is the equalization result of equalization and backward equalization, is composed, a diversity effect can be obtained, and waveform equalization can be performed with good performance even when there is a large fluctuation in the propagation path within a burst. You can

Further, when the equalization direction is selected as in the conventional case, the calculation process of the non-selected one becomes useless, but as in the first embodiment of the present invention, the forward equalization and the backward equalization are performed. By adopting the method of synthesizing the soft-decision information according to, there is an advantage that the calculation processing can be slightly increased and the equalization performance can be improved at the same time.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. 2, 4, and 5.

FIG. 4 is a block diagram showing the structure of the waveform equalizer according to the second embodiment of the present invention. In addition, this FIG.
The waveform equalizer shown in (1) is a decision feedback type equalizer, and a waveform equalizer of any configuration such as a linear equalizer or a lattice type equalizer can be used.

In FIG. 4, the waveform equalizer is a forward equalizer 400A, a backward equalizer 400B, and an A / D converter 40.
1, received data buffer 402, soft decision information buffer 4
08, received data time series inverter 409, soft decision information buffer 415, soft decision information time series inverter 416, reception level detector 417, multipliers 418, 419, adder 420
And a determiner 421.

The A / D converter 401 samples analog reception data and converts it into a digital data series. The digital data series converted by the A / D converter 401 is equal to the unit of the equalization processing in the reception data buffer 40.
It is configured to be stored in 2.

The forward equalizer 400A is a waveform equalizer that performs equalization in the order of reception time series, and includes a filter unit 403, a determination unit 404, a switch (SW) 405, and an error calculation unit 40.
6 and a tap coefficient updating unit 407. The soft decision information buffer 408 stores the equalized output of the forward equalizer 400A.

The backward equalizer 400B is a waveform equalizer that performs equalization in the reverse order of reception time series, and includes a filter unit 410, a determination unit 411, a switch (SW) 412, an error calculation unit 413, and It is composed of the tap coefficient updating unit 414. The reception data time series inverter 409 inverts the time series of the reception data, and performs pre-processing for backward equalization. The soft decision information buffer 415 stores the soft decision information which is the equalized output of the backward equalizer 400B. The soft-decision information time-series inverter 416 inverts the time-series of the data of the soft-decision information buffer 415 and returns the soft-decision information, which is the equalized output of the backward equalizer 400B, in the order of reception time series. Perform post-equalization processing.

The reception level detector 417 detects the reception level of the data during the training period, and the detection signal is output to the multipliers 418 and 419. The multipliers 418 and 419 weight the soft decision information by the forward equalization and the backward equalization according to the reception level, and output the weighted soft decision information to the adder 420. The adder 420 adds each of the soft-decision information weighted by the multipliers 418 and 419. The determiner 421 determines the addition result of the adder 420 and obtains a final equalized output. In this way, the bidirectional equalizer is configured by combining the results of the forward equalization and the backward equalization.

FIG. 5 is a diagram showing contents of each buffer and addition contents of the adder when the data series of FIG. 2 has information for n symbols. In FIG. 5, (a)
Shows the contents of the soft decision information buffer 408, (b) shows the contents of the soft decision information buffer 415, and (c) shows the contents of the output data of the adder 420.

Next, the operation of the waveform equalizer according to the second embodiment of the present invention will be described with reference to FIGS. 2, 4 and 5.

First, the received analog reception data is sampled by the A / D converter 401 and converted into a digital data series. Then, the converted digital data series is stored in the reception data buffer 402 for the equalization processing unit, that is, for one burst shown in FIG.

In the forward equalization training period, as shown in FIG.
The training sequence 1 shown in is input to the filter unit 403 in the order of reception time series. That is, the received data is sequentially input from time T201 to time T202. Received data corresponding to this is taken out from the received data buffer 402 and input to the filter unit 403. The filter unit 403 performs waveform equalization, and outputs soft decision information as an equalization output for forward equalization.

During this training period, the switch 40
Since 5 is connected to the contact A side, the training information is returned to the filter unit 403. Further, the training information and the soft decision information from the filter unit 403 are input to the error calculation unit 406, and the equalization error is calculated. And
The calculated equalization error and the tap coefficient of the filter unit 403 are input to the tap coefficient update unit 407, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 403. This forward equalization training is performed by repeating the above-described operation.

In the tracking period of the forward equalization, as shown in FIG.
The data sequence shown in is input to the filter unit 403 in the order of time of reception. That is, from time T202 to time T203
Received data is sequentially input in the direction of.
The received data corresponding to this is the received data buffer 402.
And is input to the filter unit 403. The filter unit 403 performs waveform equalization, and outputs soft decision information as an equalization output for forward equalization. Filter unit 403
The soft decision information output from the soft decision information buffer 408
Are stored in the order of reception time series. In addition, the filter unit 40
The soft decision information output from No. 3 is input to decision section 404, and the signal points of the symbols are decided.

During this tracking period, the switch 40
Since No. 5 is connected to the contact B side, the determined result is returned to the filter unit 403. Further, the determination result and the soft decision information from the filter unit 403 are stored in the error calculation unit 4
It is input to 06 and the equalization error is calculated. The calculated equalization error and the tap coefficient of the filter unit 403 are input to the tap coefficient update unit 407, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 403. The tracking of the forward equalization is performed by repeating the above operation. Here, when the data sequence has n symbols, the content of the soft decision information buffer 408 becomes as shown in FIG. 5A at the end of the tracking of the forward equalization.

In the backward equalization training period, FIG.
The training sequence 2 shown in is input to the filter unit 410 in the reverse order of the reception time sequence. That is, the received data is sequentially input in the direction from time T204 to time T203. The received data corresponding to this is taken out from the received data buffer 402 and input to the filter section 410 through the received data time series inverter 409. The filter unit 410 performs waveform equalization, and outputs soft decision information as an equalization output for backward equalization.

During this training period, the switch 412
Is connected to the contact A side, the training information is returned to the filter unit 410. Further, the training information and the soft decision information from the filter unit 410 are input to the error calculation unit 413 and the equalization error is calculated. Then, the calculated equalization error and the tap coefficient of the filter unit 410 are input to the tap coefficient updating unit 414, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 410. The backward equalization training is performed by repeating the above-described operation.

In the backward equalization tracking period, as shown in FIG.
The data series shown in is input to the filter unit 410 in the reverse order of the time series of reception. That is, from time T203
Received data is sequentially input in the direction of 202. The received data corresponding to this is taken out from the received data buffer 402 and received data time series inverter 409.
Through the filter unit 410. The filter unit 410 performs waveform equalization, and outputs soft decision information as an equalization output for backward equalization. The soft decision information output from the filter unit 410 is stored in the soft decision information buffer 415 in the order of reception time series. Further, the soft decision information output from the filter unit 410 is input to the decision unit 411, and the signal point of the symbol is decided.

In this tracking period, the switch 41
Since No. 2 is connected to the contact B side, the determined result is returned to the filter unit 410. Further, the determination result and the soft decision information from the filter unit 410 are stored in the error calculation unit 4
It is input to 13, and the equalization error is calculated. The calculated equalization error and the tap coefficient of the filter unit 410 are input to the tap coefficient updating unit 414, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 410. This reverse equalization tracking is performed by repeating the above-described operation. Here, when the data sequence includes n symbols, the content of the soft decision information buffer 415 becomes as shown in FIG.

On the other hand, the received data is the received level detector 41.
7, the reception level during the training period is calculated. That is, the reception level of the part of the training sequence 1 shown in FIG. 2 is calculated, and this is input to the multiplier 418 as the forward training period level. Further, the reception level of the portion of the training sequence 2 shown in FIG. 2 is calculated, and this is input to the multiplier 419 as the backward training period level.

After the processing of the forward equalization and the backward equalization is completed, the soft decision information by the forward equalization and the soft decision information by the backward equalization are combined. At this time, the soft decision information buffer 408 stores the soft decision information shown in FIG. 5A, and the soft decision information buffer 415 stores the soft decision information shown in FIG. 5B. At the time of the combination, soft decision information corresponding to the reception time is combined.

That is, the soft decision information by the backward equalization is taken out from the soft decision information buffer 415 and inputted to the multiplier 419 through the soft decision information time series inverter 416. The soft decision information obtained by the forward equalization is taken out from the soft decision information buffer 408 and input to the multiplier 418 as it is.

The multiplier 418 multiplies the soft decision information by the forward equalization by the forward training period level, and the multiplication result is input to the adder 420. Then, the multiplier 419 multiplies the soft decision information by the backward equalization and the backward training period level, and the multiplication result is input to the adder 420. This multiplication processing operation is weighting processing before combining soft decision information by forward equalization and soft decision information by backward equalization, and the higher the reception level during the training period, the better the equalization performance. It is intended to improve the performance by utilizing the fact that there is.

The adder 420 adds the soft-decision information by the forward equalization and the soft-decision information by the backward equalization, which are weighted by the reception level in the training period, and the addition result is input to the decider 421. It Here, when the data sequence has n symbols, the addition result input to the determiner 421 is as shown in FIG. Judge 4
At 21, the signal points of the symbols are determined, and the equalized output that is the final equalized result is obtained. In addition, in FIG.
The reception level in the forward equalization training period is a, and the reception level in the reverse equalization training period is b.

According to the second embodiment of the present invention as described above, the same effect as in the first embodiment described above can be obtained, and the weighting is performed by the reception level in the training period.
Since the soft-decision information obtained by the forward equalization and the soft-decision information obtained by the backward equalization are added and the final equalized output is obtained from the addition result, a waveform having better performance than that of the first embodiment. An equalizer can be realized.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIGS. 2, 6, and 7.

FIG. 6 is a block diagram showing the structure of the waveform equalizer according to the third embodiment of the present invention. In addition, this FIG.
The waveform equalizer shown in (1) is a decision feedback type equalizer, and a waveform equalizer of any configuration such as a linear equalizer or a lattice type equalizer can be used.

In FIG. 6, the waveform equalizer is a forward equalizer 600A, a backward equalizer 600B, and an A / D converter 60.
1, received data buffer 602, soft decision information buffer 6
08, equalization error buffer 609, received data time series inverter 610, soft decision information buffer 616, equalization error buffer 617, equalization error time series inverter 618, weighting calculation means 619, weighting buffer 620, soft decision information time Sequence inverter 621, multipliers 622 and 623, adder 62
4, a judging device 625 and a C / N estimating means 626 are provided.

The A / D converter 601 samples analog reception data and converts it into a digital data series. The digital data series converted by the A / D converter 601 is equal to the equalization processing unit in the reception data buffer 60.
It is configured to be stored in 2.

The forward equalizer 600A is a waveform equalizer that performs equalization in the order of reception time series, and comprises a filter unit 603,
Judgment unit 604, switch (SW) 605, error calculation unit 6
06, and a tap coefficient updating unit 607. The soft decision information buffer 608 stores the equalized output of the forward equalizer 600A. The equalization error buffer 609 stores the equalization error for each equalization step in forward equalization.

The backward equalizer 600B is a waveform equalizer that performs equalization in the reverse order of the reception time series, and includes a filter unit 61.
1, a determination unit 612, a switch (SW) 613, an error calculation unit 614, and a tap coefficient update unit 615. The reception data time series inverter 610 inverts the time series of the reception data and performs pre-processing for backward equalization. The soft decision information buffer 616 stores the soft decision information which is the equalized output of the backward equalizer 600B. Further, the equalization error buffer 617 stores the equalization error for each equalization step in the backward equalization.

The equalization error time series inverter 618 inverts the time series of the data of the equalization error buffer 617, and performs processing to restore the time series order of the equalization error corresponding to the equalization output of each step. . The weighting calculation means 619 determines the weighting for combining the soft decision information which is the equalization output of the forward equalization and the soft decision information which is the equalization output of the backward equalization from the equalization error in each direction. The weighting buffer 620 also stores the weighting determined by the weighting calculation means 619. The soft decision information time-series inverter 621 includes the soft decision information buffer 6
Inverse equalizer 600B for inverting the time series of 16 data
The soft decision information, which is the equalization output of, is returned in the order of time of reception, and the post-processing of backward equalization is performed.

Multipliers 622 and 623 multiply the forward equalization soft decision information or the backward equalization soft decision information by the weighting for the forward equalization or the backward equalization stored in weighting buffer 620. , And output to the adder 624. The adder 624 adds each of the soft-decision information weighted by the multipliers 622 and 623. The determiner 625 determines the addition result of the adder 624 and obtains a final equalized output. In this way, the bidirectional equalizer is configured by combining the results of the forward equalization and the backward equalization.

FIG. 7 is a diagram showing the contents of each buffer and the addition contents of the adder when the data series of FIG. 2 has information for n symbols. In FIG. 7, (a)
Shows the contents of the soft decision information buffer 608, (b) shows the contents of the equalization error buffer 609, (c) shows the contents of the soft decision information buffer 616, and (d) shows the contents of the equalization error buffer 617. e) and (f) show the contents of the weighting buffer 620 and (g) the contents of the output data of the adder 624, respectively.

Next, the operation of the waveform equalizer according to the third embodiment of the present invention will be described with reference to FIGS. 2, 6 and 7.

First, the received analog reception data is sampled by the A / D converter 601 and converted into a digital data series. Then, the converted digital data series is stored in the reception data buffer 602 for an equalization processing unit, that is, for one burst shown in FIG.

In the training period for forward equalization, as shown in FIG.
The training sequence 1 shown in is input to the filter unit 603 in the order of reception time series. That is, the received data is sequentially input from time T201 to time T202. Received data corresponding to this is taken out from the received data buffer 602 and input to the filter unit 603. The filter unit 603 performs waveform equalization, and outputs soft decision information as an equalization output for forward equalization.

During this training period, the switch 60
Since No. 5 is connected to the contact A side, the training information is returned to the filter unit 603. Further, the training information and the soft decision information from the filter unit 603 are input to the error calculation unit 606, and the equalization error is calculated. And
The calculated equalization error and the tap coefficient of the filter unit 603 are input to the tap coefficient updating unit 607, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 603. This forward equalization training is performed by repeating the above-described operation.

In the tracking period of the forward equalization, as shown in FIG.
The data sequence shown in is input to the filter unit 603 in the order of time of reception. That is, from time T202 to time T203
Received data is sequentially input in the direction of.
The received data corresponding to this is the received data buffer 602.
And is input to the filter unit 603. The filter unit 603 performs waveform equalization, and outputs soft decision information as an equalization output for forward equalization. Filter unit 603
The soft decision information output from the soft decision information buffer 608
Are stored in the order of reception time series. In addition, the filter unit 60
The soft decision information output from No. 3 is input to decision section 604, and the signal point of the symbol is decided.

In this tracking period, the switch 605
Is connected to the contact B side, the result of determination is fed back to the filter unit 603. Further, the determination result and the soft decision information from the filter unit 603 are stored in the error calculation unit 60.
6 and the equalization error is calculated. Then, the calculated equalization error and the tap coefficient of the filter unit 603 are input to the tap coefficient updating unit 607, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 603. The tracking of the forward equalization is performed by repeating the above operation. Here, when the data sequence has n symbols, the contents of the soft decision information buffer 608 at the end of the tracking of the forward equalization are as shown in FIG.
(A), and the equalization error buffer 60
The contents of 9 are as shown in FIG.

In the backward equalization training period, as shown in FIG.
The training sequence 2 shown in is input to the filter unit 611 in the reverse order of the reception time sequence. That is, the received data is sequentially input in the direction from time T204 to time T203. The received data corresponding to this is taken out from the received data buffer 602 and input to the filter unit 611 through the received data time series inverter 610. The filter unit 611 performs waveform equalization, and outputs soft decision information as an equalization output for backward equalization.

During this training period, the switch 61
Since No. 3 is connected to the contact A side, the training information is returned to the filter unit 611. Further, the training information and the soft decision information from the filter unit 611 are input to the error calculation unit 614 and the equalization error is calculated. And
The calculated equalization error and the tap coefficient of the filter unit 611 are input to the tap coefficient updating unit 615, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 611. This backward equalization training is performed by repeating the above-described operation.

In the backward equalization tracking period, as shown in FIG.
The data sequence shown in is input to the filter unit 611 in the reverse order of the reception time sequence. That is, from time T203 to time T2
The received data will be sequentially input in the 02 direction. The received data corresponding to this is the received data buffer 6
02, and is input to the filter unit 611 through the received data time series inverter 610. Filter unit 61
At 1, waveform equalization is performed, and soft decision information is output as an equalization output for backward equalization. The soft decision information output from the filter unit 611 is stored in the soft decision information buffer 616 in the reverse order of the reception time series. Further, the soft decision information output from the filter unit 611 is input to the decision unit 612, and the signal point of the symbol is decided.

In this tracking period, the switch 613
Is connected to the contact B side, the result of determination is fed back to the filter unit 611. Further, the result of the determination and the soft decision information from the filter unit 611 are the error calculation unit 61
4 and the equalization error is calculated. Then, the calculated equalization error and the tap coefficient of the filter unit 611 are input to the tap coefficient updating unit 615, and a new tap coefficient that reduces the equalization error is calculated. The calculated tap coefficient is set as a new tap coefficient of the filter unit 611. Further, the equalization error for each equalization step of the backward equalization, which is the output of the error calculation unit 614, corresponds to the data storage order of the soft decision information buffer 616 in the equalization error buffer 617 in the reverse order of the time series. Stored in. This reverse equalization tracking is performed by repeating the above-described operation. Here, when the data sequence has n symbols, the content of the soft decision information buffer 616 becomes as shown in FIG. 7C at the end of tracking of the backward equalization.
The contents of the equalization error buffer 617 are as shown in FIG. 7 (d).

After the processing of the forward equalization and the backward equalization described above is completed, the soft decision information by the forward equalization and the soft decision information by the backward equalization are combined to obtain the respective soft decision information. Weighting of the determination information is determined by the weighting calculation means 619.

At this time, the equalization error buffer 609 stores the equalization error at each equalization step due to the forward equalization as shown in FIG.
They are stored in chronological order as shown in (b), and
The equalization error buffer 617 stores the equalization error for each equalization step due to the backward equalization, as shown in FIG. Further, the weighting is determined by the equalization error corresponding to the equalization output of each equalization step as the reception time. Therefore, the equalization error due to the backward equalization is taken out from the equalization error buffer 617, and the weighting calculation means 619 is passed through the equalization error time series inverter 618.
Is output to. Further, the equalization error due to the forward equalization is taken out from the equalization error buffer 609 and directly output to the weighting calculation means 619.

The weighting calculation means 619 uses the equalization error at each equalization step due to the forward equalization and the backward equalization to obtain the soft decision information due to the forward equalization and the soft decision information due to the backward equalization. Are weighted for each symbol and stored in the weighting buffer 620 in chronological order. Here, when the data sequence has n symbols, the content of the weighting data stored in the weighting buffer 620 is as shown in FIG. 7E when the soft decision information by the forward equalization is used, and in the reverse order. In the case of soft decision information by directional equalization, it becomes as shown in FIG.

When the weighting of the combination is determined, the soft decision information by the forward equalization and the soft decision information by the reverse forward equalization are combined based on the weighting data stored in weighting buffer 620. At this time, the soft decision information buffer 60
8 stores the soft decision information by the forward equalization shown in FIG. 7A, and the soft decision information buffer 616 stores the soft decision information by the reverse forward equalization shown in FIG. 7C. At the time of combining, soft decision information corresponding to the reception time is combined.

Therefore, at the time of synthesis, soft decision information by backward equalization is fetched from the soft decision information buffer 616,
It is input to the multiplier 623 through the soft decision information time series inverter 621. The soft decision information by the forward equalization is taken out from the soft decision information buffer 608 and input to the multiplier 622 as it is. Then, the weighting data for the soft decision information by the forward equalization is input from the weighting buffer 620 to the multiplier 622, and the weighting data for the soft decision information by the backward equalization is input from the weighting buffer 620 to the multiplier 623. .

The multiplier 622 multiplies the soft-decision information for each data symbol by forward equalization by the corresponding weighting, and the result is input to the adder 624. The multiplier 623 multiplies the soft-decision information for each data symbol by backward equalization by the corresponding weighting, and the result is input to the adder 624. The adder 624 performs addition processing on the soft decision information by weighted forward equalization and the soft decision information by weighted backward equalization, and the result is the decision unit 625.
Entered in. Here, when the data sequence has n symbols, the addition result input to the determiner 625 is as shown in FIG.
As shown in (g). The determiner 625 determines the signal points of the symbols and obtains the final equalization result, the equalized output.

Next, the weight determining method by the weight calculating means 619 will be described.

Here, the weighting calculation means the data stored in the equalization error buffer 609 as shown in FIG. 7B, and the data stored in the equalization error buffer 617 as shown in FIG. 7D. It means calculating a weighting for each equalization step for synthesizing soft decision information by forward equalization and soft decision information by backward equalization from data.
The calculation result is stored in the weighting buffer 620 as shown in FIGS.

First, the weight determining method by the weight calculating means 619 will be described with reference to FIG. Figure 8
FIG. 3 is a diagram showing the contents of each buffer when the data series shown in FIG. 2 has information for n symbols. In FIG. 8, (a) shows equalization error data by the forward equalization of the equalization error buffer 609, (b) shows weight data for the soft decision information by the forward equalization of the weighting buffer 620, (c). () Shows weight data for soft decision information by the backward equalization of the weighting buffer 620, and (d) shows equalization error data by the backward equalization of the equalization error buffer 617.

In this case, the weight to the soft decision information by the forward equalization shown in FIG. 8 (b) is determined by the equalization error data of the forward equalization error buffer 609 (see FIG. 8 (a)). The reciprocal is calculated by the weighting calculation means 619 for each equalization step. That is, the equalization error data for the forward equalization is Ef.
_i (i = 0, 1, ..., N−1), the weight a _i (i = 0, 1, ...
, N-1) is calculated by a _i = 1 / Ef _i .

Similarly, the weight to the soft decision information by the backward equalization shown in FIG. 8C is the equalization error data of the backward equalization error buffer 617 (see FIG. 8D). Is calculated by the weighting calculation means 619 for each equalization step. That is, the equalization error data for the backward equalization is E
b _i (i = 0, 1, ..., N−1), the weight b _i (i = 0, 1, ...
, N-1) is calculated by b _i = 1 / Eb _i .

The weighting calculation means 619 is realized by executing the above-mentioned calculation. However, when the signal level is not related to the judgment in the judging device 625, the weighting to the soft judgment information by the forward equalization is performed. Then, the weight to the soft decision information by the backward equalization has only to be correct. in this case,
Weights a _i (i = 0, _i to the soft decision information by forward equalization,
, ..., N−1), a _i = Eb _i, and weight b _i (i = 0,1, ...) For soft decision information by backward equalization
, N−1) may be set to b _i = Ef _i , which eliminates the need to obtain the reciprocal and is effective in reducing the amount of calculation.

Next, another embodiment of the weight determining method by the weight calculating means 619 will be described with reference to FIG.

FIG. 9 shows stored data related to the m-th symbol in the data series. In FIG. 9, (a) shows equalization error data by the forward equalization of the equalization error buffer 609, and (b) shows a weighting buffer 620.
The weight data for the soft decision information by the forward equalization of
(C) shows the weight data for the soft decision information by the backward equalization of the weighting buffer 620, and (d) shows the equalization error data by the backward equalization of the equalization error buffer 617.

In this case, the weight for the soft decision information by the forward equalization shown in FIG. 9B is equalized error data for several symbols before and after each equalization step by the forward equalization (see FIG. 9).
As a reciprocal of the sum of (a), the weighting calculation means 61
9 is calculated for each equalization step.

[0125] For example, when calculating the weight in consideration of the two symbols prior to equalization error data, the weight a _m to soft decision information on forward _{equalization, a m = 1 / (Ef} m -2 + E
It is calculated as f _{m -1} + Ef _m ).

Similarly, the weighting on the soft decision information by the backward equalization shown in FIG. 9C is performed by equalizing error data for several symbols before and after each equalization step by the backward equalization (see FIG. 9).
(D)) as the reciprocal of the sum of
9 is calculated for each equalization step.

For example, in the case where the weight is calculated by adding the previous two symbols of the equalization error data, the weight b _m to the soft decision information by the backward equalization is b _m = 1 / (Eb _{m -2} + E
It is calculated as b _{m -1} + Eb _m ).

The weight calculation means 619 is realized by executing the above-mentioned calculation. However, when the signal level is not related to the judgment by the judgment unit 625, the weight to the soft judgment information by the forward equalization is applied. Then, the weight to the soft decision information by the backward equalization has only to be correct.

Next, still another embodiment of the weight determining method by the weight calculating means 619 will be described with reference to FIG.

FIG. 10 shows stored data concerning symbols in the vicinity of the m-th data series. In FIG. 10, (a) shows equalization error data by the forward equalization of the equalization error buffer 609, and (b) shows the weighting buffer 6.
The weight data for the soft decision information by the forward equalization of 20 is
(C) shows the weight data for the soft decision information by the backward equalization of the weighting buffer 620, and (d) shows the equalization error data by the backward equalization of the equalization error buffer 617.

In this case, the weight to the soft decision information by the forward equalization shown in FIG. 10B is equalized to the equalization error data by the forward equalization (see FIG. 10A). An equalization error with a forgetting factor, which introduces a forgetting factor λ (0 ≦ λ ≦ 1), is calculated for each step and is given as the reciprocal thereof.

Now, the weight a _m for the soft decision information by the forward equalization is calculated. At this time, the equalization error with the forgetting factor for the symbol m-1 is given as the reciprocal of the weight in the symbol m-1, and thus becomes 1 / am _-1 . Using this, the equalization error with forgetting factor for symbol m is λ /
a _m-1 + Ef _m , and the weight a _m is its reciprocal, a
It is determined by _m = 1 / (λ / a _m-1 + Ef _m ).

Similarly, the weighting on the soft decision information by the backward equalization shown in FIG. 10C is performed for each equalization error data by the backward equalization (see FIG. 10D). An equalization error with a forgetting factor, which introduces a forgetting factor λ (0 ≦ λ ≦ 1), is calculated for each step and is given as the reciprocal thereof.

Now, the weight b _m for the soft decision information by backward equalization is calculated. At this time, the equalization error with the forgetting factor for the symbol m-1 is given as the reciprocal of the weight in the symbol m-1, and thus becomes 1 / b _m-1 . Using this, the equalization error with forgetting factor for symbol m is λ /
b _m-1 + Ef _m , and the weight b _m is its reciprocal, b
It is determined by _m = 1 / (λ / b _m-1 + Ef _m ).

The weighting calculation means 619 is realized by executing the above-mentioned calculation. However, when the signal level is not relevant to the decision made by the decision unit 625, the soft decision information is weighted by the forward equalization. Then, the weight to the soft decision information by the backward equalization has only to be correct.

Next, as shown in FIG. 6, a case will be described in which C / N (average carrier power to noise power ratio) estimating means 626 is added to weighting calculating means 619 to perform weighting calculation.

When the C / N of the received data is good, a small value is set for the forgetting factor λ (0 ≦ λ ≦ 1) so that equalization performance is not degraded and the fluctuation of the propagation path is tracked at high speed. It is possible to realize a waveform equalizer. Also, the C / N of the received data
If is not good, the effect of thermal noise can be minimized by setting a large value for the forgetting factor λ, which contributes to the improvement of equalization performance.

Therefore, the C / N estimating means 626 calculates the C / N estimated value by inputting the received data, the equalization error and the like, and the C / N estimated value is weighted by the weight calculating means 619.
To enter. When the C / N estimated value is large, the weighting calculation means 619 sets a small forgetting factor λ, and C / N
When the estimated value is small, weighting is calculated by setting a large forgetting factor λ.

As described above, the third embodiment has a configuration in which the weighting is changed for each data symbol in combining soft decision information by forward equalization and soft decision information by backward equalization. Therefore, a waveform equalizer that is more resistant to channel fluctuations and has better equalization performance, as compared with the second embodiment in which constant weighting is performed for each equalization processing unit such as one burst as a whole and synthesis is performed. Can be realized.

Further, the performance improvement degree of the waveform equalizer changes depending on the weighting method in the weighting calculation means 619. When this is realized in, for example, a mobile communication system, desired performance of the entire system, propagation path conditions, Alternatively, it may be selected according to the margin of the amount of calculation of the LSI mounted on the mobile radio device.

(Embodiment 4) In a large zone type mobile communication system, a mobile communication system with a high transmission speed, etc., when a plurality of radio wave propagation paths exist between a base station and a mobile station, these paths are used. The effect of multipath fading, such as intersymbol interference caused by the difference, cannot be ignored.

In the present invention, however, the above-mentioned problem can be solved by using the waveform equalizer having the configuration shown in FIGS. 1, 4 and 6 described above. Therefore, the mobile radio apparatus and the base station radio apparatus using the waveform equalizer of the present invention become terminals and base station infrastructure with good reception performance, and the mobile communication system constructed by a combination of these has multipath fading. It is a strong, high-quality system.

[0143]

As described above, according to the waveform equalizer of the present invention, the diversity effect is obtained by adding and synthesizing the two operation results of the forward equalization and the backward equalization. It is possible to perform waveform equalization with good performance even when the propagation path changes drastically within a burst.

Further, the waveform equalizer of the present invention weights the soft decision information in each direction by utilizing the fact that the higher the reception level during the training period, the better the equalization performance tends to be. By synthesizing and determining the result, it is possible to follow up with good performance even in the case where the fluctuation of the propagation path is large in the burst, and perform waveform equalization with better performance.

Further, according to the waveform equalizer of the present invention, attention is paid to the equalization error which is also an index of equalization performance, and the soft decision information in each direction is weighted and combined by the weighting calculated from the equalization error. As a result, a greater diversity effect can be obtained, and by determining the synthesis result, waveform equalization can be performed with good performance even when the propagation path changes drastically within the burst.

Further, according to the waveform equalizer of the present invention, the reciprocal of the equalization error for each equalization step is weighted as it is, so that it is possible to provide a waveform equalizer with a small calculation amount and good performance. .

Further, according to the waveform equalizer of the present invention, not only the equalization error in a certain equalization step but also the equalization errors before and after the equalization error can be taken into consideration to determine the weighting. It is possible to avoid an erroneous determination in the waveform equalizer due to a drop in the reception level for a short time, and to provide a waveform equalizer with good performance.

Also, according to the waveform equalizer of the present invention, the reception C /
The influence of thermal noise when N becomes small is reduced, and a waveform equalizer with good performance can be provided.

Further, according to the waveform equalizer of the present invention, C /
By setting the forgetting factor according to the N estimated value, when the receiving quality is good, the small forgetting factor is used to improve the tracking speed to the propagation path, and when the receiving quality is bad, the large forgetting factor is used. The influence of thermal noise can be reduced and the performance of the waveform equalizer can be further improved.

Further, according to the present invention, in a large zone type mobile communication system, a mobile communication system having a high transmission speed, etc., a mobile radio terminal or a base station used in an environment in which the influence of multipath fading cannot be ignored. Even in infrastructure, it is possible to improve reception performance in response to various propagation path conditions.

Further, according to the present invention, it is possible to provide a high quality mobile communication system that is resistant to multipath fading, and to easily construct a large zone type mobile communication system or a mobile communication system having a high transmission speed. Have an effect.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a waveform equalizer according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of received data

FIG. 3 is an explanatory diagram showing the contents of each buffer when the data sequence has information for n symbols in the first embodiment of the present invention.

FIG. 4 is a configuration diagram of a waveform equalizer according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram showing contents of each buffer and addition contents of an adder when a data sequence has information for n symbols in Embodiment 2 of the present invention.

FIG. 6 is a configuration diagram of a waveform equalizer according to a third embodiment of the present invention.

FIG. 7 is an explanatory diagram showing contents of each buffer and addition contents of an adder when a data sequence has information for n symbols in Embodiment 3 of the present invention.

FIG. 8 is an explanatory diagram showing the contents of each buffer during weighting calculation according to the present invention.

FIG. 9 is an explanatory diagram showing the contents of each buffer during weighting calculation according to the present invention.

FIG. 10 is an explanatory diagram showing the contents of each buffer during weighting calculation according to the present invention.

FIG. 11 is a block diagram of a conventional waveform equalizer.

[Explanation of symbols]

100A, 400A, 600A Forward equalizer 100B, 400B, 600B reverse equalizer 101, 401, 601 A / D converter 102, 402, 602 Received data buffer 103, 403, 603 Filter section 104, 404, 604 Judgment unit 105, 405, 605 switch 106, 406, 606 Error calculation unit 107, 407, 607 Tap coefficient updating unit 108, 408, 608 Soft decision information buffer 109, 409, 610 Received data time series inverter 110, 410, 611 Filter section 111, 411, 612 Judgment unit 112, 412, 613 switch 113, 413, 614 Error calculation unit 114, 414, 615 Tap coefficient updating unit 115, 415, 616 Soft decision information buffer 116, 416, 621 Soft decision information time series inverter 117, 420, 624 adder 118,421,625 Judgment device 417 Reception level detector 418, 419, 622, 623 Multiplier 609 Equalization error buffer 617 Equalization error buffer 618 Equalization error time series inverter 619 Weighting calculation means 620 Weighting buffer 626 C / N estimation means

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ken Akiyama Ken 3 Azuma Tsunashima, Kohoku-ku, Yokohama, Kanagawa Matsushita Communication Industrial Co., Ltd. (56) Reference JP-A-8-149056 (JP, A) JP-A-5-300129 (JP, A) JP-A-3-119838 (JP, A) JP-A-7-226704 (JP, A) JP-A-6-216816 (JP, A) JP-A-6-77771 (JP, A) JP 4-11406 (JP, A) JP 7-212299 (JP, A) JP 8-56185 (JP, A) JP 5-91001 (JP, A) Kaihei 5-335894 (JP, A) JP 10-224282 (JP, A) JP 10-51366 (JP, A) JP 9-51294 (JP, A) JP 9-307488 ( JP, A) Akihiro Higashi, Hiroshi Suzuki, “Dual Mode Equalization for Digital Mobile Radio”, IEICE Transactions B-II, March 25, 1991, Vol. J74-B-II, No. 3, pp. 91-100 (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04B 1/00 H04B 3/00 H04B 7/00

Claims (16)

(57) [Claims] 1. A forward equalizer for equalizing waveforms in time series of reception of received data, a backward equalizer for equalizing waveforms in reverse order of reception of received data, and the forward equalizer. -Decision information, which is the equalization result of forward equalization of the equalizer, and soft decision information, which is the result of time-sequential inversion of the soft-decision information, which is the equalization result of backward equalization of the backward equalizer A waveform equalizer comprising: an addition unit; and a determination unit that obtains an equalized output by determining the addition result of the addition unit. 2. A forward equalizer for equalizing waveforms in the order of reception of received data, a backward equalizer for equalizing waveforms in reverse of the order of reception of received data, and training of the received data. Reception level detection means for detecting a reception level during a training period for forward equalization and a reception level during a training period for backward equalization based on period data, and equalization for forward equalization of the forward equalizer. First multiplication means for multiplying the resulting soft decision information by the reception level of the forward equalization training period, and the time series of the soft decision information which is the equalization result of the backward equalization of the backward equalizer. Second multiplication means for multiplying the inverted soft decision information by the reception level in the backward equalization training period, addition means for adding the multiplication results of the first and second multiplication means, and addition by the addition means Judge the result A waveform equalizer, characterized in that it comprises a determination means for obtaining an equalized output. 3. A forward equalizer for equalizing waveforms in time series of reception of received data, a backward equalizer for equalizing waveforms in reverse order of time series of reception of received data, and the forward equalizer. From the equalization error at each equalization step due to forward equalization of the equalizer, and determines the weighting for the soft decision information which is the equalization result of the forward equalization of the forward equalizer and the backward equalization. Weighting calculation means for determining weighting for the soft decision information which is the equalization result of the backward equalization of the backward equalizer from the equalization error at each equalization step due to the backward equalization of the equalizer, and A first multiplication unit that multiplies the soft decision information that is the equalization result of the forward equalization and the weighting determined by the weighting calculation unit, and the time series inversion of the soft decision information that is the equalization result of the backward equalization. The soft decision information afterwards and the weighting determined by the weighting calculation means A second multiplication means for multiplying, an addition means for adding the multiplication results of the first and second multiplication means, and a determination means for obtaining an equalized output by determining the addition result by the addition means. Waveform equalizer. 4. The weighting calculation means determines the weighting on the soft decision information by the forward equalization for each equalization step by the reciprocal of the equalization error by the forward equalization for each equalization step,
4. The waveform according to claim 3, wherein the weighting to the soft decision information by the backward equalization at each equalization step is determined by the reciprocal of the equalization error due to the backward equalization at each equalization step. Chemist. 5. The weighting calculation means is a reciprocal of the sum of equalization errors for several symbols before and after each equalization step by forward equalization for weighting soft decision information by forward equalization for each equalization step. And the weighting to the soft decision information by the backward equalization for each equalization step is determined by the reciprocal of the sum of equalization errors for several symbols before and after each equalization step by the backward equalization. The waveform equalizer according to claim 3, which is characterized in that. 6. The weighting calculation means calculates an equalization error with a forgetting factor into which a forgetting factor λ (0 ≦ λ ≦ 1) is introduced for each equalizing step of forward equalization, and the weighting calculating means calculates the equalizing error for each equalizing step. The weighting to the soft decision information by the forward equalization is determined by the reciprocal of the equalization error with the forgetting coefficient at each equalization step by the forward equalization, and the forgetting coefficient at each equalization step of the backward equalization. An equalization error with a forgetting factor in which λ (0 ≦ λ ≦ 1) is introduced is calculated, and the soft decision information is weighted by the backward equalization at each equalization step at each equalization step by the backward equalization. 4. The waveform equalizer according to claim 3, wherein the waveform equalizer is determined by the reciprocal of the equalization error with the forgetting factor. 7. The weighting calculation means includes a C / N estimation means, and the C / N estimation means calculates a C / N estimation value based on received data, equalization error, etc., and the C / N estimation value is calculated. 7. The waveform equalizer according to claim 6, wherein the forgetting factor λ is set according to 8. A mobile radio apparatus comprising a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is a forward equalizer for equalizing waveforms in time series of reception of received data. A backward equalizer that equalizes waveforms in the reverse order of the time series of reception of received data, soft-decision information that is the equalization result of the forward equalizer of the forward equalizer, and the backward equalizer. Addition means for adding soft decision information after time series inversion of the soft decision information which is the equalization result of the backward equalization, and a decision means for obtaining an equalized output by determining the addition result by the addition means. A mobile wireless device comprising: 9. A mobile radio apparatus comprising a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is a forward equalizer that equalizes waveforms in time series of reception of received data. A backward equalizer for equalizing waveforms in the reverse order of the time series of reception of the received data, and a reception level and a backward equalization of the training period of the forward equalization based on the data of the training period of the received data. A reception level detecting means for detecting a reception level during a training period; a soft decision information which is an equalization result of the forward equalization of the forward equalizer and a reception level during a training period for the forward equalization. 1 multiplication means, and the soft decision information after time series inversion of the soft decision information that is the equalization result of the backward equalization of the backward equalizer is multiplied by the reception level of the backward equalization training period Squared Means and, an adding means for adding the multiplication result of the first and second multiplying means, the mobile radio apparatus characterized by comprising determination means for obtaining an equalized output by determining the addition result by the adding means. 10. A mobile radio apparatus comprising a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is a forward equalizer for equalizing waveforms in time series of reception of received data. And a backward equalizer that equalizes waveforms in the reverse order of reception time series of received data, and the forward equalization from equalization error at each equalization step due to the forward equalization of the forward equalizer. Determine the weighting for the soft decision information that is the equalization result of the forward equalization of the equalizer and from the equalization error at each equalization step by the backward equalization of the backward equalizer, the backward equalization Weighting calculation means for determining weighting for the soft decision information which is the equalization result of the backward equalization of the device,
First multiplication means for multiplying the soft decision information which is the equalization result of the forward equalization and the weighting determined by the weighting calculation means, and time series inversion of the soft decision information which is the equalization result of the backward equalization Second multiplication means for multiplying the soft decision information after the multiplication with the weight determined by the weight calculation means,
A mobile radio apparatus comprising: an addition unit that adds the multiplication results of the first and second multiplication units; and a determination unit that obtains an equalized output by determining the addition result of the addition unit. 11. A base station radio apparatus including a waveform equalizer that removes the influence of frequency selective fading, wherein the waveform equalizer forward equalizes waveform equalization in time series of reception of received data. , A backward equalizer that equalizes waveforms in the reverse order of the time series of reception of received data, soft-decision information that is the equalization result of the forward equalization of the forward equalizer, and the backward equalization Means for adding soft decision information after time series inversion of the soft decision information which is the equalization result of the backward equalization of the converter, and a decision to obtain an equalized output by determining the addition result by the addition means A base station wireless device comprising means. 12. A base station radio apparatus including a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer forward equalizes waveform equalization in time series of reception of received data. And a backward equalizer for equalizing waveforms in the reverse order of reception time series of received data, and a reception level and a backward equalization during a training period of forward equalization based on data of a training period of the received data. Reception level detecting means for detecting the reception level during the training period, the soft decision information which is the equalization result of the forward equalization of the forward equalizer, and the reception level during the training period of the forward equalization are multiplied. The first multiplication means multiplies the soft-decision information after the time-series inversion of the soft-decision information, which is the equalization result of the backward equalization of the backward equalizer, by the reception level of the backward equalization training period. First A base station radio, comprising: multiplication means; addition means for adding the multiplication results of the first and second multiplication means; and determination means for obtaining an equalized output by determining the addition result by the addition means. apparatus. 13. A base station radio apparatus comprising a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer forward equalizes waveform equalization in the time series of reception of received data. An equalizer, a backward equalizer that equalizes waveforms in the reverse order of reception time series of received data, and an equalization error at each equalization step due to the forward equalization of the forward equalizer, and the forward equalizer The weighting is determined for the soft decision information that is the equalization result of the forward equalization of the equalizer, and the backward equalization is performed from the equalization error at each equalization step due to the backward equalization of the backward equalizer. Weighting calculation means for determining weighting for the soft decision information which is the equalization result of the backward equalization of the equalizer,
First multiplication means for multiplying the soft decision information which is the equalization result of the forward equalization and the weighting determined by the weighting calculation means, and time series inversion of the soft decision information which is the equalization result of the backward equalization Second multiplication means for multiplying the soft decision information after the multiplication with the weight determined by the weight calculation means,
A base station radio apparatus comprising: an addition unit that adds the multiplication results of the first and second multiplication units; and a determination unit that obtains an equalized output by determining the addition result of the addition unit. 14. A mobile communication system comprising a base station and a mobile station, wherein at least one of the base station and the mobile station comprises a waveform equalizer for removing the influence of frequency selective fading. Is a forward equalizer that equalizes waveforms in the order of reception of received data, a backward equalizer that equalizes waveforms in the reverse order of reception of received data, and the order of the forward equalizer. An addition means for adding the soft decision information which is the equalization result of the directional equalization and the soft decision information after time series inversion of the soft decision information which is the equalization result of the backward equalization of the reverse equalizer, A mobile communication system comprising: a determination unit that obtains an equalized output by determining the addition result of the addition unit. 15. A mobile communication system comprising a base station and a mobile station, wherein at least one of the base station and the mobile station comprises a waveform equalizer for removing the influence of frequency selective fading. Is a forward equalizer for equalizing waveforms in time series of reception of received data, a backward equalizer for equalizing waveforms in reverse order of reception of received data, and data of a training period of the received data. Reception level detection means for detecting the reception level during the forward equalization training period and the reception level during the backward equalization training period based on the above, and the forward equalization equalization result of the forward equalizer. First multiplication means for multiplying the soft-decision information by the reception level of the forward equalization training period, and after time-series inversion of the soft-decision information which is the equalization result of the backward equalization of the backward equalizer Soft judgment A second multiplication means for multiplying the information and the reception level in the backward equalization training period; an addition means for adding the multiplication results of the first and second multiplication means; and a determination result of the addition result by the addition means. A mobile communication system comprising a determination means for obtaining an equalized output. 16. A mobile communication system comprising a base station and a mobile station, wherein at least one of the base station and the mobile station comprises a waveform equalizer for removing the influence of frequency selective fading, wherein the waveform equalizer is provided. Is a forward equalizer that equalizes waveforms in the order of reception of received data, a backward equalizer that equalizes waveforms in the reverse order of reception of received data, and the order of the forward equalizer. From the equalization error at each equalization step due to directional equalization, weighting is determined for the soft decision information that is the equalization result of the forward equalization of the forward equalizer, and the inverse of the backward equalizer is determined. Weighting calculation means for determining weighting for the soft decision information which is the equalization result of the backward equalization of the backward equalizer from the equalization error at each equalization step due to the directional equalization,
First multiplication means for multiplying the soft decision information which is the equalization result of the forward equalization and the weighting determined by the weighting calculation means, and time series inversion of the soft decision information which is the equalization result of the backward equalization Second multiplication means for multiplying the soft decision information after the multiplication with the weight determined by the weight calculation means,
A mobile communication system comprising: an addition unit that adds the multiplication results of the first and second multiplication units; and a determination unit that obtains an equalized output by determining the addition result of the addition unit.