JP3897564B2 - Radio base station apparatus and radio communication method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radio base station apparatus and a radio communication method used in a digital radio communication system, and more particularly, to a radio base station apparatus and a radio communication method that include an adaptive array antenna and perform directional reception.
[0002]
[Prior art]
In a radio base station apparatus provided with an adaptive array antenna, only a directional beam direction can be received strongly by using a plurality of branches and directional weights. This radio base station apparatus can generate a delay profile corresponding to each directivity and find a path in which interference is suppressed.
[0003]
A case where a radio base station apparatus equipped with such an adaptive array antenna receives a signal transmitted from a communication terminal will be described with reference to FIG. FIG. 12 is a conceptual diagram showing a directional beam direction and multipath incoming waves. In FIG. 12, reference numerals 11 to 14 indicate directivity patterns, and reference numerals 15 and 16 indicate multipaths.
[0004]
In the case of FIG. 12, the conventional radio base station apparatus detects the peak of the path 16 based on the delay profile of the directivity pattern 12, and detects the peak of the path 15 based on the delay profile of the directivity pattern 12 or the directivity pattern 13. The paths are selected by arranging the peaks in descending order (in order from the path with the largest peak).
[0005]
[Problems to be solved by the invention]
However, in the above-described conventional example, in a multipath environment, a path arriving in a directivity valley (for example, between directivity 12 and directivity 13) at the time of path selection has higher power than other paths, In some cases, the demodulation accuracy is high, that is, the path that should be originally selected is not selected. Referring to FIG. 12, the path 15 can obtain a peak from a delay profile of two directivities (directivity 12 and directivity 13). However, even if the received power is the same as that of the path 16, the path 15 is affected by directivity. A loss occurs in the peak of the delay profile and is detected as a peak lower than the path 16. At this time, the path selection selects the delay profile peaks in descending order (in order from the path with the highest peak), so the path 15 may be omitted from the selection.
[0006]
The present invention has been made in view of such a point, and a radio base station apparatus and a radio that prevent a path with high demodulation accuracy that should originally be selected that has arrived between two adjacent directivity valleys from being selected. An object is to provide a communication method.
[0007]
[Means for Solving the Problems]
The radio base station apparatus of the present invention includes a first directivity generation unit that generates a plurality of directivity patterns and a signal received by the plurality of directivity patterns. Corresponding to each of the plurality of directivity patterns Delay profile generation means for generating a plurality of delay profiles; The plurality of A path search unit that corrects a peak indicating the same path appearing on the delay profile and selects a path based on the corrected peak size, and a received signal at a timing of the path selected by the path search unit. And a despreading means for despreading.
[0008]
According to this configuration, the demodulation accuracy that should be originally selected by correcting the loss of the peak on the delay profile caused by the influence of the directivity weight in the path that has arrived between two adjacent directivity valleys. It is possible to prevent a high path from being selected.
[0009]
Further, in the radio base station apparatus of the present invention, the path search means includes a peak ratio calculation means for calculating a ratio of two peak sizes by the same path, and influence of directivity based on the ratio of the peak sizes. The peak correction means for correcting the peak by estimating the loss of the peak generated in step 1 and the path selection means for performing path selection for selecting a predetermined number of corrected peaks in descending order are employed.
[0010]
In the radio base station apparatus of the present invention, the path search means includes a peak detection means for detecting a peak exceeding a predetermined threshold value on the delay profile, and two delay profiles appearing on the delay profile corresponding to the adjacent directivity pattern. The same path determination means for determining whether or not the two peaks are due to the same path based on a threshold determination between a peak phase difference and a predetermined threshold is adopted.
[0011]
According to these configurations, when a path arrives between two adjacent directivity valleys, the peak loss is calculated from the ratio of two peaks existing in substantially the same phase on the delay profile corresponding to the two adjacent directivities. Therefore, it is possible to prevent the loss of a peak with high demodulation accuracy that should be originally selected.
[0012]
The radio base station apparatus of the present invention is The plurality of When the peaks on the delay profile indicate the same path, a configuration in which second directivity generation means for generating a directivity pattern in the arrival direction of the path is employed.
[0013]
The radio base station apparatus of the present invention is The plurality of When the peaks on the delay profile indicate the same path, a configuration is adopted in which directivity is directed toward the arrival direction of the path having the largest corrected peak.
[0014]
According to these configurations, since the path to be originally selected that has arrived between two directivity valleys adjacent to each other at the time of initial reception can be received with the second directivity pattern, other paths with different arrival directions can be received. Alternatively, it is possible to reduce the influence of other mobile station transmission waves and perform path selection.
[0015]
The wireless communication method of the present invention generates a plurality of directivity patterns and uses signals received in the respective directivity patterns. Corresponding to each of the plurality of directivity patterns Generate multiple delay profiles, The plurality of A peak indicating the same path appearing on the delay profile is corrected, path selection is performed based on the corrected peak size, and the received signal is despread at the timing of the selected path.
[0016]
According to this method, it is possible to prevent a path with high demodulation accuracy that should be originally selected that has arrived between two adjacent directivity valleys from being selected.
[0017]
The wireless communication method of the present invention includes: The plurality of When the peaks on the delay profile indicate the same path, a directivity pattern is generated in the arrival direction of the path.
[0018]
According to this method, it is possible to perform path selection while reducing the influence of other paths having different arrival directions or other mobile station transmission waves.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
The essence of the present invention is that a base station apparatus equipped with an adaptive array antenna generates a delay profile corresponding to each directivity, and there is a peak indicating the same path on a delay profile corresponding to two adjacent directivities. Based on the ratio calculated from the sizes of the two peaks, the path is selected after correcting the peak loss due to directivity.
[0020]
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0021]
(Embodiment 1)
In this embodiment, when a path arrives between two adjacent directivity valleys, on the delay profile corresponding to the two adjacent directivities, from the magnitude of the peak of the same path detected at substantially the same phase. A case where a correction value is calculated based on the calculated ratio and a peak loss due to directivity is corrected will be described.
[0022]
1 is a block diagram showing a configuration of a radio base station apparatus according to Embodiment 1 of the present invention. It has a plurality of adaptive array antennas 101 (three in FIG. 1), and outputs a signal (received signal) received via each adaptive array antenna 101 to the received signal converter 102. Reception signal conversion section 102 performs processing such as down-conversion, quadrature demodulation, and analog-digital conversion processing on the reception signal, and then outputs the processed signal to directivity generation section 104 and to despreading section 107 To do.
[0023]
The directivity information generation unit 103 recognizes the amount of change in amplitude and phase for each branch, which is input information from the outside, as one group, and associates the directivity angle with several groups in advance as a parameter. Based on this, the corresponding parameter is selected and output to the directivity generation unit 104 and the path search unit 106.
[0024]
The directivity generation unit 104 receives the reception signal from the reception signal conversion unit 102 by multiplying the reception signal from the directivity information generation unit 103 by the directivity weight of the angle at which the beam is to be directed based on the parameter output from the directivity information generation unit 103. The signal is rotated in phase, and the multiplication results are added and synthesized to generate directivity, and the received signal of each directivity is output to the delay profile generation unit 105.
[0025]
Four delay profile generation units 105 are provided in the present embodiment, and each directional reception signal obtained by the directivity generation unit 104 is correlated with a known spreading code, and the correlation is obtained. Generate a delay profile that represents the time variation of the value. Here, delay profiles corresponding to signals received in four directivities can be generated. Each generated delay profile is output to the path search unit 106.
[0026]
The path search unit 106 detects the peak of each delay profile output from the delay profile generation unit 105 and corrects the peak based on a predetermined condition such as a parameter generated by the directivity information generation unit 103. A path is selected and the despreading unit 107 is notified of the path timing. Details of processing in the path search unit 106 will be described later.
[0027]
The despreading unit 107 assigns the timing of the path selected by the path search unit 106 to the finger, and restores the signal before spreading by multiplying the received signal by a spreading code corresponding to the wireless terminal. Then, despreading section 107 outputs the despread signal to demodulation section 108.
[0028]
The demodulator 108 demodulates the despread signal output from the despreader 107 to obtain an information signal.
[0029]
Next, the internal configuration of the path search unit 106 will be described in detail with reference to FIG. The peak detection unit 201 detects a peak exceeding a predetermined threshold based on each delay profile generated by the delay profile generation unit 105, and outputs the peak and peak timing to the same path determination unit 202. The same path determination unit 202 determines whether or not the peak detected by the peak detection unit 201 is due to the same path, and outputs the determination result to the peak ratio calculation unit 203. The detailed description of the same path determination unit 202 will be described later.
[0030]
The peak ratio calculation unit 203 calculates a ratio (hereinafter referred to as “peak ratio”) from the magnitudes of two peaks determined by the same path determination unit 202 as being from the same path, and the calculated result is the peak correction unit 205. Output to. A detailed description of the peak ratio calculation unit 203 will be described later.
[0031]
The angle / gain calculation unit 204 calculates the directivity angle and gain (gain) based on the directivity information generated by the directivity information generation unit 103, obtains the directivity pattern, and outputs the directivity pattern to the peak correction unit 205. To do.
[0032]
The peak correction unit 205 calculates a correction value based on the peak ratio calculated by the peak ratio calculation unit 203 and the directivity pattern calculated by the angle / gain calculation unit 204, and multiplies the corresponding peak by the calculated correction value. Then, the corrected peak is output to the path selection unit 206.
[0033]
The path selection unit 206 selects a predetermined number of paths in descending order of the corrected peaks output from the peak correction unit 205 and notifies the despreading unit 107 of the path timing.
[0034]
Next, the operation of the radio base station apparatus having the above configuration will be described. A signal (reception signal) received via each adaptive array antenna 101 is subjected to processing such as down-conversion, quadrature demodulation, and analog-digital conversion processing in the reception signal conversion unit 102, and then reversely transmitted to the directivity generation unit 104. It is output to the diffusion unit 107.
[0035]
Information on the amount of change in amplitude and phase with respect to each branch input from the outside to the directivity information generation unit 103 is regarded as one group by the directivity information generation unit 103 and is directed to several groups in advance. The angle of the sex is associated as a parameter, and the corresponding parameter is selected based on this, and is output to the directivity generation unit 104 and the path search unit 106.
[0036]
A plurality of signals output from the reception signal conversion unit 102 are multiplied by the directivity weight of the angle at which the beam is to be directed, based on the parameters output from the directivity information generation unit 103 in the directivity generation unit 104. The results are added and combined to generate directivity. For each directional reception signal, delay profile generation section 105 generates a delay profile corresponding to each directivity based on each directional reception signal. In the generated delay profile, a peak is detected in the path search unit 106, path selection is performed based on a predetermined condition such as a parameter generated by the directivity information generating unit 103, and the path timing is despread. It is output to 107.
[0037]
The plurality of processed signals output from the received signal conversion unit 102 are despread in the despreading unit 107 based on the timing of the path selected by the path search unit 106 and output to the demodulation unit 108. . The signal after despreading is demodulated in the demodulator 108 to obtain an information signal.
[0038]
Next, the operation in the path search unit 106 will be described. The peak detection unit 201 detects a peak exceeding a predetermined threshold based on each delay profile generated by the delay profile generation unit 105, and outputs the peak size and peak timing to the same path determination unit 202. . The peaks detected by the peak detection unit 201 are aligned in the same path determination unit 202 according to the magnitude of the phase value (in descending order) for each delay profile. Then, the largest peak and the peak obtained from the directivity adjacent to each other are compared, and it is determined whether or not the same path exists.
[0039]
As a result of comparing the peaks, if it is determined that there is the same path, the peak size and the peak timing are output to the peak ratio calculation unit 203. On the other hand, if it is determined that there is no same path, the size of the reference peak is reduced in order until a peak determined to be the same path is found with reference to the peak that is the timing of the next largest peak. The peak obtained from the matching directivity is compared, and the same determination as described above is performed. When there are no more comparison candidates, the process proceeds to the next frame process.
[0040]
Since the same path determination unit 202 determines that two peaks obtained from adjacent directivities are the same path, the peak ratio calculation unit 203 calculates the two peak ratios, and the calculation result Is output to the peak correction unit 205.
[0041]
The angle / gain calculation unit 204 calculates the directivity angle and gain (gain) based on the directivity information (parameters) generated by the directivity information generation unit 103, obtains the directivity pattern, and corrects the peak. Is output to the unit 205.
[0042]
The peak correction unit 205 calculates a correction value based on the peak ratio calculated by the peak ratio calculation unit 203. Then, the larger one of the corresponding peaks in the delay profile output from the delay profile generation unit 105 is multiplied by the correction value calculated by the peak ratio calculation unit 203. The other peak that has not been corrected is excluded from the path selection target. The delay profile obtained in this way is output to the path selection unit 206.
[0043]
The path selection unit 206 selects a predetermined number of paths in descending order of the corrected peaks output from the peak correction unit 205, and notifies the despreading unit 107 of the path timing.
[0044]
Next, the same path determination method in the same path determination unit 202 will be described in detail. FIG. 3 is a diagram illustrating processing for determining the same path from the delay profile corresponding to each directivity. The left side of FIG. 3 shows the delay profiles of the four directivities A to D generated by each delay profile generation unit 105. The right side of FIG. 3 shows how the peaks that appear in each delay profile are aligned according to the magnitude of the phase value. The maximum peak on the right side of FIG. 3, that is, the peak 304 of directivity C is detected, and the phase value of the directivity C and the peak obtained from the directivity B or directivity D adjacent to each other is compared. Specifically, a difference (phase difference) between the phase values of two peaks is obtained, and when the phase difference is equal to or smaller than a predetermined threshold (Z) (| X−Y | ≦ Z, X, Y: two to be compared Peak phase value), it is determined that these two peaks are due to the same path. In this case, it is determined that the directivity B peak 302 having the phase value X is caused by the same path as the directivity C peak 304 having the phase value Y. If the same path as the maximum peak 304 is not found, the reference peak is determined in descending order, and the phase value between the reference peak and the peak obtained from the adjacent directivity is compared. That is, when there is no peak showing the same path as the peak 304, the phase value between the directivity B and the peak obtained from the directivity A or directivity C adjacent to the directivity B is calculated based on the peak 302 next to the peak 304. Compare. If there is no peak showing the same path as the peak 302, the peak 306 next to the peak 302 is compared with a peak obtained from the directivity adjacent to the peak 302, and the same path is determined. The same path determination is performed until all peaks are compared.
[0045]
Next, a peak ratio calculation method in the peak ratio calculation unit 203 will be described. FIG. 4 is a diagram showing peaks detected at substantially the same phase from the delay profiles of two adjacent directivities (corresponding to directivity B and directivity C in FIG. 3). Let a be the magnitude of the peak 302 detected from the delay profile of directivity B, and let b be the magnitude of the peak 304 detected from the delay profile of directivity C. When the ratio of the magnitudes of a and b is a: b = 1: 1.8, the correction value for correcting the peak loss and the path arrival direction are determined from this peak ratio. FIG. 5 is a diagram for determining the correction value and the arrival direction of the path from the peak ratio of the delay profiles of directivity B and directivity C. The vertical axis in FIG. 5 indicates the loss power [dB] generated at the peak of the delay profile, and the horizontal axis indicates the arrival direction [degree] of the path. As an example, the peak ratio on the right vertical axis is a: b = 1: 1.8. Reference numeral 501 indicates a characteristic curve of directivity B, and reference numeral 502 indicates a characteristic curve of directivity C. Reference numeral 503 indicates that the peak ratio of the delay profile of directivity B and directivity C corresponds to a: b = 1: 1.8, and corresponds to FIG. That is, the path shown in FIG. 4 has a peak a of 6 [dB], a peak b of 1.5 [dB] loss, and the path arrival direction is +5 [degrees]. Thereby, the peak power and the arrival direction of the path shown in FIG. 4 can be determined. Note that the arrival direction is determined in the second embodiment. As shown in FIG. 6, by correcting the larger peak b by 1.5 [dB], it can be equivalent to the peak value when not affected by the directivity weight. Note that the smaller peak a that has not been corrected is excluded from the path selection target.
[0046]
FIG. 7 is a diagram showing peaks detected at substantially the same phase from the delay profiles of two adjacent directivities (corresponding to directivity B and directivity C in FIG. 3). However, it is assumed that the peak size a of directivity B and the peak size b of directivity C are the same. That is, a: b = 1: 1, which corresponds to the reference numeral 504 with reference to FIG. It can be seen that the peak a and the peak b are respectively lost by 3 [dB], and that the arrival direction is 0 degrees (a path arrives exactly in the middle between the directivity B and the directivity C). From this, it can be seen that the two peaks shown in FIG. 7 are lost by 3 [dB]. Since these two peaks have the same value, either one of the peaks is corrected by 3 [dB]. This is shown in FIG. As shown in FIG. 8, it can be equivalent to the peak value when not affected by the directivity weight. The other peak that has not been corrected is excluded from the path selection target.
[0047]
If no corresponding peak is detected between −10 [degrees] and +10 [degrees] in FIG. 5 from the two delay profiles, it is determined that no path has arrived between adjacent directivity valleys. Correction processing is not performed.
[0048]
As described above, according to the present embodiment, when a path arrives between two adjacent directivity valleys, the ratio of two peaks present in substantially the same phase on the delay profile corresponding to the two adjacent directivities. Therefore, it is possible to estimate the correction value for correcting the peak loss and correct the peak loss due to directivity, so that it is possible to prevent the path with high demodulation accuracy to be originally selected from being selected.
[0049]
(Embodiment 2)
In the present embodiment, when a path arrives between two directivity valleys adjacent to each other, if there is a peak of the same path detected in substantially the same phase on the delay profile corresponding to the two directivities, A case will be described in which the arrival direction is estimated from the peak ratio and dynamic directivity described later is assigned to the arrival direction.
[0050]
FIG. 9 is a block diagram showing a configuration of the radio base station apparatus according to the present embodiment. In FIG. 9, the same reference numerals as those in FIG.
[0051]
The directivity information generation unit 901 views the amount of change in amplitude and phase for each branch, which is input information from the outside, as one group, and associates the directivity angle with several groups as parameters in advance. The corresponding parameter is selected and output to the directivity generation unit 902.
[0052]
The directivity generation unit 902 receives the reception signal from the reception signal conversion unit 102 by multiplying the reception signal from the reception signal conversion unit 102 by the directivity weight of the angle at which the beam is aimed based on the parameter output from the directivity information generation unit 901. The signal is rotated in phase, and the multiplication results are added and synthesized to generate directivity, and the received signal of each directivity is output to the delay profile generation unit 105.
[0053]
The directivity generation unit 902 forms three or more directional reception signals so that the delay profile generation unit 105 generates three or more delay profiles, and one of the directional reception signals is directional. If there is directivity information generated by the path search unit 903, a received signal corresponding to the directivity is formed. This directivity is hereinafter referred to as “dynamic directivity”, and a path search before the dynamic directivity is directed in a desired direction is referred to as “initial path search”.
[0054]
The path search unit 903 detects the peak of each delay profile generated by the delay profile generation unit 105, performs path selection based on a predetermined condition, and outputs the path timing to the despreading unit 107. In addition, directivity information of dynamic directivity is generated and output to the directivity generation unit 902.
[0055]
Next, the internal configuration of the path search unit 903 will be described in detail with reference to FIG. The peak detection unit 1001 detects a peak exceeding a predetermined threshold based on each delay profile corresponding to the directivity other than the dynamic directivity generated by the delay profile generation unit 105, and the peak and peak timing are the same. The result is output to the path determination unit 1002. The same path determination unit 1002 determines whether the peak detected by the peak detection unit 1001 is due to the same path, and outputs the determination result to the peak ratio calculation unit 1003.
[0056]
The peak ratio calculation unit 1003 calculates a ratio from the sizes of two peaks determined to be the same path by the same path determination unit 1002, and outputs the calculation result to the peak correction unit 1005 and the arrival direction estimation unit 1007. .
[0057]
The angle / gain calculation unit 1004 calculates the directivity angle and gain (gain) from the directivity information generated by the directivity information generation unit 901, obtains the directivity pattern, and the peak correction unit 1005 and the arrival direction estimation Output to the unit 1007.
[0058]
The peak correction unit 1005 calculates a correction value based on the directivity pattern calculated by the angle / gain calculation unit 1004 and the peak ratio calculated by the peak ratio calculation unit 1003, and multiplies the corresponding peak by the calculated correction value. Then, the corrected peak is output to the path selection unit 1006.
[0059]
When performing the initial path search, the path selection unit 1006 ignores the delay profile corresponding to the dynamic directivity, selects a predetermined number of paths in descending order of the corrected peaks output from the peak correction unit 1005, The despreading unit 107 is notified of the path timing. In addition, after the initial path search, there is a delay profile corresponding to the dynamic directivity directed to the direction of the path that has arrived between adjacent directivity valleys (the arrival direction of the path having the largest corrected peak). Based on only this delay profile, path selection is performed, and the despreading unit 107 is notified of the path timing.
[0060]
Based on the directivity pattern calculated by the angle / gain calculation unit 1004 and the peak ratio calculated by the peak ratio calculation unit 1003, the arrival direction estimation unit 1007 calculates the arrival direction of the path that has arrived in the adjacent directivity valley. The estimation result is notified to the dynamic directivity generation unit 1008. The dynamic directivity generation unit 1008 generates a parameter for assigning dynamic directivity to the arrival direction of a path that has arrived between adjacent directivity valleys (the arrival direction of the path having the largest corrected peak). Output to the sex generation unit 902.
[0061]
Next, the operation of the path search unit 903 having the above configuration will be described. First, a case where an initial path search is performed will be described. The peak detection unit 1001 detects a peak exceeding a predetermined threshold based on each delay profile generated by the delay profile generation unit 105, and outputs the peak and peak timing to the same path determination unit 1002. The peaks detected by the peak detection unit 1001 are arranged in the same path determination unit 1002 according to the magnitude of the phase value (in descending order) for each delay profile. Then, the largest peak and the peak obtained from the directivity adjacent to each other are compared, and it is determined whether or not the same path exists.
[0062]
As a result of comparing the peaks, if it is determined that there is the same path, this determination result is output to the peak ratio calculation unit 1002. On the other hand, if it is determined that there is no same path, the size of the reference peak is reduced in order until a peak determined to be the same path is found with reference to the peak that is the timing of the next largest peak. The peak obtained from the matching directivity is compared, and the same determination as above is performed. When there are no more comparison candidates, the process proceeds to the next frame process.
[0063]
Since the same path determination unit 1002 determines that two peaks obtained from adjacent directivities are the same path, the peak ratio calculation unit 1003 calculates the ratio from the magnitudes of the two peaks. The calculation result is output to the peak correction unit 1005 and the arrival direction estimation unit 1007.
[0064]
The angle / gain calculation unit 1004 calculates the directivity angle and gain (gain) based on the directivity information generated by the directivity information generation unit 901, obtains the directivity pattern, and the peak correction unit 1005 It is output to the arrival direction estimation unit 1007.
[0065]
The peak correction unit 1005 calculates a correction value based on the peak ratio calculated by the peak ratio calculation unit 1003. Then, the larger one of the corresponding peaks in the delay profile output from the delay profile generation unit 105 is multiplied by the correction value calculated by the peak ratio calculation unit 1003. The other peak that has not been corrected is excluded from the path selection target. The delay profile obtained in this way is output to the path selection unit 1006.
[0066]
The path selection unit 1006 selects a predetermined number of paths in descending order of the corrected peaks output from the peak correction unit 1005, and notifies the despreading unit 107 of the path timing.
[0067]
The arrival direction estimation unit 1007 estimates the arrival direction of a path that has arrived between adjacent directivity valleys based on the result calculated by the peak ratio calculation unit 1003, and notifies the dynamic directionality generation unit 1008 of the estimation result. Is done. In the dynamic directivity generation unit 1008, based on the result estimated by the arrival direction estimation unit 1007, the arrival direction of the path arriving between adjacent directivity valleys (the arrival direction of the path having the largest corrected peak) is set. A directivity weight for assigning dynamic directivity is generated and output to the directivity generation unit 902.
[0068]
Next, after the initial path search will be described. The directivity weight of the dynamic directivity generated by the dynamic directivity generation unit 1008 is multiplied by the received signal of the path that has arrived in the adjacent directivity valley in the directivity generation unit 902 to generate directivity. The FIG. 11 shows a conceptual diagram in which dynamic directivity is assigned to the arrival direction of the path (the arrival direction of the path having the largest corrected peak). In FIG. 11, when there are directivity 1101 to 1103, the dynamic directivity 1104 is assigned to a path that has reached the valley between the directivity 1101 and the directivity 1102.
[0069]
The dynamic directivity received signal is output to the delay profile generator 105, and a delay profile corresponding to the dynamic directivity is generated. The path selection unit 1006 performs path selection based only on the delay profile generated by the delay profile generation unit 105, and obtains the timing of the selected path. The despreading unit 107 is notified of the path timing obtained by the path selection unit 1006.
[0070]
As described above, according to the present embodiment, it is possible to receive a path to be originally selected that has arrived between two directivity valleys adjacent to each other at the time of initial reception using a dynamic directivity pattern. Path selection can be performed while reducing the influence of other paths or other mobile station transmission waves.
[0071]
In the present embodiment, the initial path search includes the operation of directing the dynamic directivity in the direction of the path arriving between adjacent directivity valleys, but the configuration in which the dynamic directivity is directed in the arrival direction of this path in advance. In this case, the peak correction unit 1005 is not necessary. For this reason, it is possible to facilitate the circuit configuration because the above-described effects are obtained and the need for providing the peak correction unit 1005 is eliminated.
[0072]
【The invention's effect】
As described above, according to the present invention, when a path arrives between two adjacent directivity valleys, the ratio of two peaks that are substantially in phase on a delay profile corresponding to two adjacent directivities. Therefore, it is possible to reproduce a delay profile in which the influence of directivity is reduced, so that it is possible to prevent a path with high demodulation accuracy that should be originally selected from being selected.
[Brief description of the drawings]
1 is a block diagram showing a configuration of a radio base station apparatus according to Embodiment 1 of the present invention;
FIG. 2 is a block diagram showing an internal configuration of a path search unit according to the first embodiment of the present invention.
FIG. 3 is a diagram illustrating a process for determining the same path from a delay profile corresponding to each directivity.
FIG. 4 is a diagram showing peaks detected at substantially the same phase from delay profiles corresponding to two adjacent directivities.
FIG. 5 is a diagram for determining a correction value and a path arrival direction from a peak ratio of delay profiles of directivity B and directivity C;
FIG. 6 is a diagram showing a corrected peak in a directivity C delay profile;
FIG. 7 is a diagram showing peaks detected at substantially the same phase from delay profiles corresponding to two adjacent directivities.
FIG. 8 is a diagram showing a corrected peak in a delay profile of directivity B
FIG. 9 is a block diagram showing a configuration of a radio base station apparatus according to Embodiment 2 of the present invention.
FIG. 10 is a block diagram showing an internal configuration of a path search unit according to the second embodiment of the present invention.
FIG. 11 is a conceptual diagram showing a dynamic directivity beam direction and an incoming wave according to Embodiment 2 of the present invention;
FIG. 12 is a conceptual diagram showing the directivity beam direction and multipath arrival waves.
[Explanation of symbols]
101 Adaptive array antenna
102 Received signal converter
103, 901 Directivity information generator
104, 902 Directivity generator
105 Delay profile generator
106, 903 Path search part
107 Despreading section
108 Demodulator
201, 1001 Peak detector
202, 1002 Same path determination unit
203, 1003 Peak ratio calculator
204, 1004 Angle / gain calculation unit
205, 1005 Peak correction unit
206, 1006 Path selection unit
1007 Arrival direction estimation unit
1008 Dynamic directivity generator

Claims (7)

First directivity generation means for generating a plurality of directivity patterns;
Delay profile generation means for generating a plurality of delay profiles respectively corresponding to the plurality of directivity patterns from signals received in the plurality of directivity patterns ;
Path search means for correcting a peak indicating the same path appearing on the plurality of delay profiles and selecting a path based on the corrected peak size;
Despreading means for despreading the received signal at the timing of the path selected by the path search means;
A radio base station apparatus comprising: The path search means includes a peak ratio calculation means for calculating a ratio of two peak sizes due to the same path,
Peak correction means for correcting a peak by estimating a peak loss caused by directivity based on a ratio of peak sizes;
Path selection means for performing path selection for selecting a predetermined number of corrected peaks in descending order;
The radio base station apparatus according to claim 1, comprising: The path search means includes peak detection means for detecting a peak exceeding a predetermined threshold on the delay profile; and
Same path determination means for determining whether or not the two peaks are due to the same path based on threshold determination between a phase difference between two peaks appearing on a delay profile corresponding to adjacent directivity patterns and a predetermined threshold When,
The radio base station apparatus according to claim 2, comprising: The second directivity generation means for generating a directivity pattern in an arrival direction of the path when peaks on the plurality of delay profiles indicate the same path. Wireless base station device. 2. The radio base station apparatus according to claim 1, wherein when the peaks on the plurality of delay profiles indicate the same path, directivity is directed toward the arrival direction of the path with the largest corrected peak. Generate multiple directional patterns,
Generating a plurality of delay profiles respectively corresponding to the plurality of directivity patterns from signals received in each directivity pattern;
Correcting a peak indicating the same path appearing on the plurality of delay profiles;
A radio communication method characterized by performing path selection based on the corrected peak size and despreading the received signal at the timing of the selected path. The radio communication method according to claim 6, wherein , when peaks on the plurality of delay profiles indicate the same path, a directivity pattern is generated in an arrival direction of the path.

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