JP2005311914A - Radio receiver and radio receiving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect a path corresponding to each mobile station exactly and improve accuracy in demodulation. <P>SOLUTION: A delay profile is divided into each user window, which corresponds to a unit mid-amble shift amount W, and each user window is enlarged by a back and forth t chip. The front half of the enlarged window is considered as a foregoing window and the rear half as a back window, and each peak, which is over a prescribed value, appearing at each foregoing window and each back window is detected as a signal path transmitted from a user corresponding to the window. A despreading object, which is detected at the foregoing window, at a position of the path is considered as one symbol of the primary data unit head of an advance wave and a despreading object, which is detected at the back window, at a position of the path is considered as one symbol of the secondary data unit tail end of a delay wave. Then, a ratio Ps/Pd between a power Ps per chip calculated from the despreading result for each one symbol of the first and second data unit and a power Pd per chip calculated from a correlation value power at the peak of a delay profile is compared with a prescribed threshold, and thereby whether the path is active or not is determined. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a radio reception apparatus and radio reception method that perform path detection, and is suitable for application to, for example, a base station apparatus that removes an interference component from a received signal based on a path detection result.

  In general, in a digital mobile communication system, when a base station that receives a signal transmitted from each mobile station demodulates a signal from a certain mobile station, a signal from another mobile station is included in the signal as an interference component. Since they are superposed, it is necessary to remove this interference component, and the base station is provided with an interference cancellation device. Patent Document 1 describes a mobile station that performs demodulation by removing interference.

  FIG. 15 shows a mobile communication system including a base station provided with an interference canceller. In the mobile communication system shown in FIG. 15, the base station BS performs wireless communication with K mobile stations (only mobile station # 1 and mobile station #K are shown in FIG. 15) existing in the cell CL. I do. In this mobile communication system, a TDD (Time Division Duplex) communication method is used.

  FIG. 16 is a diagram showing the structure of the frame format and slot format of the TD-SCDMA system. As shown in the figure, one frame is formed of two subframes, one subframe is seven slots, a guard period (hereinafter referred to as “GP”) and a DwPTS in which a SYNC-DL code is stored, and a SYNC. -It is formed by UpPTS in which UL code and GP are stored. A GP is inserted between DwPTS and UpPTS. Here, the SYNC-DL code and the SYNC-UL code are a downlink synchronization code and an uplink synchronization code for acquiring synchronization between the base station and the mobile station.

  Slot # 0 can be flexibly allocated to the downlink, and slots # 1 to # 6 can be flexibly allocated to the uplink and downlink. In this figure, slot # 0 and slots # 2 to # 6 are allocated to the downlink, and the base station shows a state in which transmission to the mobile station is performed using these slots. On the other hand, slot # 1 is assigned to the uplink, and the mobile station shows transmission to the base station using this slot.

  In this uplink slot # 1, a midamble code (mid-amble in the figure) unique to each mobile station between information signals (data part in the figure) spread by a spreading code (channelization code) unique to each mobile station. Signal) is multiplexed for the number of users, and a guard period (GP) is provided to prevent collision with the adjacent downlink slot # 2. This midamble code is used when performing channel estimation for each mobile station.

  Next, generation of a midamble code unique to each mobile station will be described with reference to FIG. FIG. 17 is a schematic diagram showing a method for generating a midamble code by the base station BS.

  First, a basic midamble code mp whose code length is P is prepared. FIG. 17 shows a case where two basic midamble codes mp are connected. The basic midamble code mp is a code unique to the cell CL, and is a code known to all the mobile stations # 1 to #K in the cell CL.

Next, the head chip position is designated for mobile stations # 1 to #K. Specifically, for mobile station # 1, a position shifted by (K−1) × W chips from the reference position is designated as the top chip position. Here, K (also expressed as K _cell ) represents the number of midamble codes generated from the basic midamble code, and W represents the shift amount. Hereinafter, W is referred to as a unit midamble shift amount. For mobile station # 2, a position shifted by (K−2) × W chips from the reference position is designated as the top chip position. In this way, the leading chip position designated for each mobile station is given a position shifted by W chips. That is, for mobile station #K, the reference position is designated as the first chip position.

  Finally, the midamble code is formed by cutting out the basic midamble code by Lm chips from the top chip position for each mobile station. As a result, unique midamble codes having different midamble shift amounts are generated for the respective mobile stations # 1 to #K. Actually, it is formed by cyclically shifting a basic midamble code unique to a cell by a unit shift amount.

  Referring to FIG. 15 again, each mobile station multiplexes the unique midamble code as described above in the same slot and transmits it to the base station BS in the cell CL.

  On the other hand, the base station BS performs a correlation operation using the received signal and the cell-specific basic midamble code mp prepared in advance, so that the transmission signals from all the mobile stations # 1 to #K are transmitted as shown in FIG. A delay profile as shown in (a) is generated.

  Here, when this delay profile is divided into detection windows (W in FIG. 18) corresponding to the unit shift amount W of the basic midamble code, each detection window W has a path of a signal transmitted from each mobile station. The corresponding peak appears. That is, since the midamble code of each mobile station is shifted by the unit midamble shift amount W, each mobile station (user # 1 to user # 1 in the figure) is obtained by cyclically shifting the basic midamble code mp and calculating the correlation. The delay profiles for K) appear within the detection window W in time series.

  Next, the base station BS performs a path limiting process on the generated delay profile in order to improve channel estimation accuracy and reduce the amount of calculation. Specifically, the base station BS removes a path whose peak size is equal to or smaller than a threshold value from all the existing paths in the generated delay profile, thereby causing a delay as illustrated in FIG. Form a profile.

  Thereby, the base station BS recognizes a path appearing in the delay profile in each detection window among the delay profiles after path limitation as a path of a signal transmitted from each mobile station. That is, the path appearing in the delay profile in the detection window at the left end in the figure is recognized as the path of the signal transmitted from the user # 1. Further, the path appearing in the delay profile in the second detection window from the left is recognized as the path of the signal transmitted from the user # 2. Similarly, the path appearing in the delay profile in the detection window at the right end is recognized as the path of the signal transmitted from the user #K. As described above, since the path detected in each detection window is determined for each user, hereinafter, the detection windows for detecting the paths of signals transmitted from users # 1 to #K are referred to as user windows # 1 to #K, respectively. I will call it.

  Next, the base station BS uses the channel estimation values of all received signals and the spreading codes assigned to all the mobile stations # 1 to #K (users # 1 to #K), which is a known technique. By performing detection processing, an interference component is removed from the received signal.

  In the mobile communication system using such a midamble code, the length of the unit midamble shift amount W that is a base for identifying each mobile station shown in FIG. 15 is 3GPP specification TS25.221 V4.7.0. Is defined as follows.

First, when the length of the basic midamble code described above is P [chip] and the number of midamble codes generated from the basic midamble code is K _cell , the unit midamble shift amount W [chip] is expressed by the following equation. It is represented by (1).

式（１）は、ベーシックミッドアンブルコードＰをミッドアンブルコードの個数Ｋ_cellで除算した値を越えない最大の整数が単位ミッドアンブルシフト量Ｗとなることを示している。このようにして求められる単位ミッドアンブルシフト量Ｗの長さは、各移動局＃１〜＃Ｋからの送信信号についての最大遅延時間に対応する長さより大きくなるように設定される。なお、最大遅延時間とは、基地局ＢＳが送信した信号が移動局に到達するまでの時間に相当し、セルＣＬの半径に基づいて決まる時間である。例えば、図１５を参照するに、移動局＃１からの信号は、パスＡを介して基地局ＢＳに到達する時間のみならず、パスＢを介して（図ではセルＣＬの端の反射体で反射すると仮定する）基地局ＢＳに到達する時間も考慮されている。
特開２００２−１１１５４２号公報

Equation (1) indicates that the maximum integer not exceeding the value obtained by dividing the basic midamble code P by the number of midamble codes K _cell is the unit midamble shift amount W. The length of the unit midamble shift amount W obtained in this way is set to be larger than the length corresponding to the maximum delay time for the transmission signals from the mobile stations # 1 to #K. The maximum delay time corresponds to the time until the signal transmitted from the base station BS reaches the mobile station, and is determined based on the radius of the cell CL. For example, referring to FIG. 15, the signal from the mobile station # 1 is transmitted not only through the time to reach the base station BS through the path A but also through the path B (in the figure, the reflector at the end of the cell CL). The time to reach the base station BS (assuming reflection) is also taken into account.
JP 2002-111542 A

  However, in the mobile communication system, there is a possibility that a path whose delay time exceeds the time corresponding to the unit midamble shift amount W may occur. In the technique described in Patent Document 1, when the delay time exceeds the unit midamble shift amount W, accurate path detection processing for signals from each mobile station becomes difficult, and is obtained by interference cancellation processing at the base station. The signal quality will deteriorate.

  Hereinafter, a specific description will be given with reference to FIG. 19 while paying attention to mobile station # 2 (hereinafter referred to as user # 2). FIG. 19 shows a delay profile after path limitation generated by the base station BS. In this figure, user windows # 1 to # 3 are shown, and the window widths of the user windows # 1 to # 3 are defined as a break corresponding to the unit midamble shift amount W.

  In FIG. 19A, the path P3 of the signal from the user # 3 does not appear in the user window # 3 because the user # 3 has advanced the transmission timing due to erroneous control or the like. Appears in # 2.

  In FIG. 19B, when the signal from the user # 1 has a delay exceeding the maximum delay time, the path P1 does not appear in the user window # 1, but appears in the user window # 2.

  As a result, in the case of FIG. 19A, the base station misrecognizes the path P3 of the user # 3 as the path of the user # 2. Similarly, in the case of FIG. 19B, the base station misrecognizes the path P1 of the user # 1 as the path of the user # 2.

  Thereafter, the base station solves an equation for interference removal based on such misrecognized path information, and thus cannot perform interference removal satisfactorily. Therefore, the quality of the signal obtained by the interference cancellation process is deteriorated.

  In addition, in the base station BS, when more mobile stations are allocated to one transmission time slot, that is, when transmitting to more mobile stations in the same time, the unit midamble shift amount W It is necessary to shorten the length. In such a case, the possibility that a path whose delay time exceeds the unit midamble shift amount W will be further increased, so that the interference removal capability in each mobile station is further reduced.

  The present invention has been made in view of this point, and an object of the present invention is to provide a radio reception apparatus and a radio reception method that accurately detect a path corresponding to each mobile station and improve demodulation accuracy.

  The radio reception apparatus of the present invention uses a midamble code unique to each mobile station formed by cyclically shifting a cell-specific basic midamble code by a unit shift amount as a midamble part, and the midamble part is multiplexed at the same time A wireless reception device that receives a signal from a communication partner, and by taking a correlation while cyclically shifting the plurality of midamble units included in the received signal and the cell-specific basic midamble code prepared in advance, A delay profile generating means for generating a delay profile and a user window having a window width corresponding to a unit shift amount of the basic midamble code are used to divide the delay profile and communicate peaks exceeding a predetermined value appearing in each user window A path that detects the position of the path as the path of the signal transmitted from the other party. Among the first data part and the second data part time-division multiplexed with the position detection means and the midamble part, a predetermined part corresponding to the path position appearing in the user window corresponds to the user window Whether or not the despreading means for despreading at the path position using the channelization code assigned to the user and the despread data path based on the power of the despread data symbol is a valid path And determining means for determining whether or not.

  According to this configuration, among the first data portion and the second data portion that are time-division multiplexed with the midamble portion interposed therebetween, a predetermined portion corresponding to the path position that appears in the user window is assigned to the user corresponding to the user window. By despreading at the path position using the channelization code assigned to each and determining whether the despread path of the data part is a valid path based on the power of the despread data symbol, The user judgment of the path can be performed with high accuracy, and it is determined whether the path is for the user targeted for the user judgment or the path that has appeared beyond the corresponding user window (hereinafter referred to as “path beyond the window”). be able to.

  In the wireless receiver according to the present invention, in the above configuration, the path position detecting unit transmits a peak that is greater than or equal to a predetermined value that appears in a window obtained by enlarging the window width of each user window by a predetermined amount before and after the window. As a path, a configuration for detecting the position of the path is adopted.

  According to this configuration, the position of each user window is detected as a path of a signal transmitted from the communication partner by detecting a peak equal to or greater than a predetermined value that appears in a window obtained by enlarging the window width by a predetermined amount before and after the window width. By determining whether or not the path at the path position is a valid path, the path near the boundary of the user window is likely to be a path beyond the window, and corresponds to the user window to be determined by the user. Or a path corresponding to an adjacent user window.

  In the wireless receiver according to the present invention, in the above configuration, the path position detection unit uses a front half of each user window as a leading window and a rear half as a rear window, and is equal to or greater than a predetermined value appearing in the preceding window and the rear window. A configuration is adopted in which the position of the path is detected as a path of a signal transmitted from the communication partner.

  According to this configuration, the front half of each user window is a leading window and the back half is a back window, and predetermined first and second data portions are determined in accordance with the path positions detected in the preceding and rear windows. By despreading the part, for example, when a preceding wave and delayed wave path with a shift equal to the spreading code length of the data portion appears in one user window, the leading wave and delayed wave are greatly interfered with each other between the codes. However, it is possible to accurately determine the user of each path, and to determine whether the path is for the user as a user determination target or a path beyond the window.

  In the wireless receiver of the present invention, in the above-described configuration, the despreading unit sets a target to be despread at the path position detected in the preceding window as the first data portion head, and the path position detected in the rear window. A configuration is adopted in which the object to be despread is the tail of the second data part.

  According to this configuration, the target to be despread at the path position detected in the preceding window is the first data portion head, and the target to be despread at the path position detected in the rear window is the second data portion tail. For example, when a preceding wave and a delayed wave path having a shift equal to the spreading code length of the data portion appear in one user window, the leading wave and the delayed wave cause a large interference between the codes. There is no delayed signal that interferes with the first data portion of the wave, and there is no preceding signal that interferes with the second data portion of the delayed wave. It can be performed well, and it can be determined whether the path is for the user to be determined by the user or a path that has passed through the window.

  In the wireless receiver of the present invention, in the above configuration, the despreading means despreads the path position detected in the preceding window as the first data portion head and the second data portion head, and the rear A configuration is adopted in which the object to be despread at the path position detected by the window is the tail of the first data portion and the tail of the second data portion.

  According to this configuration, a target to be despread at the path position detected in the preceding window is set as the head of each of the first and second data parts, and a target to be despread at the path position detected in the rear window is the first and second. Since the symbol gain can be improved and the influence of noise can be reduced by using the last two data parts, user determination can be performed with high accuracy.

  In the above configuration, the wireless reception device of the present invention comprises reception quality measurement means for measuring reception quality of the received signal, and the despreading means is configured to use the preceding window if the reception quality is a predetermined value or more. The target to be despread at the detected path position is the first data portion head, the target to be despread at the path position detected at the rear window is the second data portion tail, and the reception quality is less than a predetermined value. If so, the object to be despread at the path position detected in the preceding window is the first data part head and the second data part head, and the object to be despread at the path position detected in the rear window is the A configuration is adopted in which the first data portion ends and the second data portion ends.

  According to this configuration, if the reception quality is equal to or greater than a predetermined value, the despreading target is the first data portion head and the second data portion end, and if the reception quality is less than the predetermined value, the despreading target is the first. And by making each head of the second data part and each tail of the first and second data parts, even when the reception quality is poor, the user judgment of each path can be performed accurately, and the user judgment target It is possible to determine whether the user's path is a path beyond the window.

  In the above configuration, the wireless reception device of the present invention comprises power ratio calculation means for calculating a power ratio between the peak power of the delay profile and the power of the despread data portion, and the determination means includes: If the power ratio is equal to or greater than a predetermined value, a configuration is adopted in which a path at a path position where the data portion is despread is determined as an effective path.

  According to this configuration, by calculating the power ratio between the peak power of the delay profile and the power of the despread data part, the power ratio excluding the influence of the reception state can be expressed as a predetermined threshold value. Can be accurately performed, so that the user determination of each path can be performed with high accuracy.

  In the above-described configuration, the wireless reception device according to the present invention is configured so that when the determination unit has a window width of the user window equal to or greater than twice the spreading code length of the data portion, a predetermined value is set before and after the boundary between the preceding window and the rear window. A configuration is adopted in which a path detected in a chip area is unconditionally determined as a valid path.

  According to this configuration, when the window width of the user window is more than twice the spreading code length of the data portion, there is no path detected in a predetermined chip area before and after the boundary between the preceding window and the rear window. By determining that the path is valid for the condition, the path of user judgment in the preceding window and the rear window does not appear in the path of the preceding wave and the delayed wave with a deviation of the spread code length, and the user judgment of each path is accurate. It can be performed well, and it can be determined whether the path is for the user to be determined by the user or a path that has passed through the window.

  In the wireless receiver of the present invention, in the above configuration, the determination unit uses a channelization code assigned to a user corresponding to one user window at a path position detected near a boundary with an adjacent user window. The power of the despread data part is compared with the power of the data part despread using the channelization code assigned to the user corresponding to the other user window. A configuration is adopted in which the path is determined to be valid.

  In the wireless receiver of the present invention, in the above configuration, the determination unit uses a channelization code assigned to a user corresponding to one user window at a path position detected near the boundary between adjacent user windows. The power of the despread data part and the power of the data part despread using the channelization code assigned to the user corresponding to the other user window are both less than a predetermined value and the path is invalid. When the determination is made, a configuration is adopted in which both powers are compared in size, and the user's path from which large power is obtained is determined to be valid.

  According to these configurations, since the path at the path position detected near the boundary with the adjacent user window is likely to be a path beyond the window, the channelization code corresponding to one user window is used. The power of the despread data part is compared with the power of the despread data part using the channelization code corresponding to the other user window, and the path of the user who has obtained a large power is determined to be valid. Thus, even if the path passes through the window, the user can be surely determined.

  In the wireless receiver of the present invention, in the above configuration, the determination unit indicates whether or not the path at the path position where the data part is despread is an effective path with a weight according to the power of the despread data part Take the configuration.

  According to this configuration, the path at the path position where the data part is despread is indicated as an effective path with the weight according to the power of the despread data part, so that the weight is reflected for each path. The demodulation accuracy can be improved by RAKE-combining the despread data part signal or by using a weighted path in the convolution process in JD.

  The base station apparatus of the present invention employs a configuration including any one of the above-described radio reception apparatuses. Further, the mobile station apparatus of the present invention employs a configuration including any one of the above-described radio reception apparatuses.

  According to these configurations, of the first data portion and the second data portion that are time-division multiplexed with the midamble portion interposed therebetween, a predetermined portion corresponding to the path position that appears in the user window corresponds to the user window. Based on the power of the despread data part using the channelization code assigned to the user, it is determined whether the path at the despread data part is a valid path. Thus, the user determination of each path can be performed with high accuracy, and it is possible to determine whether the path is a user determination target user path or a path beyond a window.

  According to the radio reception method of the present invention, the midamble part is multiplexed at the same time with the midamble code unique to each mobile station formed by cyclically shifting the basic midamble code specific to the cell by the unit shift amount. A wireless reception method for receiving a signal from a communication partner, wherein the plurality of midamble parts included in a received signal and a correlation are obtained while cyclically shifting the cell-specific basic midamble code prepared in advance, A delay profile generating step for generating a delay profile and a user window having a window width corresponding to a unit shift amount of the basic midamble code are used to divide the delay profile and communicate peaks exceeding a predetermined value appearing in each user window. A path that detects the position of the path as the path of the signal transmitted from the other party. Corresponding to the user window, a predetermined portion corresponding to the path position appearing in the user window among the first data part and the second data part time-division multiplexed with the position detection step and the midamble part interposed therebetween A despreading step for despreading at the path position using a channelization code assigned to the user to be used, and whether or not the path obtained by despreading the data portion is a valid path based on the power of the despread data symbol And a determination step for determining whether or not.

  According to this method, among the first data part and the second data part that are time-division multiplexed with the midamble part in between, a predetermined part corresponding to the path position that appears in the user window is assigned to the user corresponding to the user window. By despreading at the path position using the channelization code assigned to each and determining whether the despread path of the data part is a valid path based on the power of the despread data symbol, The user determination of the path can be performed with high accuracy, and it can be determined whether the path is for the user to be determined by the user or a path beyond the window.

  As described above, according to the present invention, the user window in which the delay profile is divided by the unit midamble shift amount W is enlarged by a predetermined amount in the front and rear, the front half of the enlarged window is the leading window, and the rear half is the rear window. Second peak data obtained by detecting a peak greater than or equal to a predetermined value as a path and despreading the first data portion at the path position detected by the preceding window and the path position detected by the rear window. The despreading result at the end of the part is represented by the power per unit according to the reception state, and a predetermined threshold value and a threshold value are determined respectively, so that a plurality of intervals equal to the spreading code length of the data part within one user window can be obtained. Even when a path is detected, the user determination of each path can be performed with high accuracy, and it is possible to determine whether the path is for the user as a user determination target or a path beyond a window.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a base station apparatus according to Embodiment 1 of the present invention. In this figure, a radio unit 102 down-converts a radio frequency signal (received RF signal) received via an antenna 101 into a baseband signal band and performs quadrature detection. A / D conversion section 103 converts the analog signal output from radio section 102 into a digital signal (received BB signal), and outputs the received BB signal to correlation calculation section 105, user determination section 107 and demodulation section 108.

  Pilot code sequence generation section 104 generates a cell-specific basic midamble code (pilot code sequence), and outputs the generated basic midamble code to correlation calculation section 105.

  Correlation calculation section 105 performs correlation calculation with the received BB signal output from A / D conversion section 103 while cyclically shifting the basic midamble code output from pilot code sequence generation section 104 at a time interval of a certain sampling frequency. Is performed over a predetermined interval. The correlation value obtained by this correlation calculation is the channel estimation value itself indicating the amount of phase rotation and the amount of amplitude fluctuation in the radio propagation path. The correlation value calculated by the correlation calculation is output to the user determination unit 107.

  The channelization code generation unit 106 generates a channelization code unique to the mobile station, and outputs the generated channelization code to the user determination unit 107 and the demodulation unit 108.

  The user determination unit 107 generates a delay profile based on the correlation value output from the correlation calculation unit 105, and detects a peak greater than a predetermined value from the delay profile divided by the unit midamble shift amount W as a path. Then, the user determination unit 107 uses the channelization code output from the channelization code generation unit 106 for the portion corresponding to the position where the peak appears in the data part of the received BB signal output from the A / D conversion unit 103. Use despreading. Further, the user determination unit 107 compares the power ratio between the power per chip of the signal after despreading and the power per chip of the peak in the delay profile with a predetermined threshold, and the path of the signal transmitted from any user To determine. This is called user determination. The demodulator 108 is notified of the user-determined path timing (path position). Details of the user determination unit 107 will be described later.

  The demodulation unit 108 uses the correlation value output from the correlation calculation unit 105, the channelization code output from the channelization code generation unit 106, and the path position notified from the user determination unit 107, and uses the A / D conversion unit 103. The data part of the received BB signal output from is demodulated, and the demodulation result is output.

  FIG. 2 is a block diagram showing an internal configuration of user determining unit 107 according to Embodiment 1 of the present invention. In this figure, the delay profile generation unit 201 continuously obtains the square sum (correlation value power) of the in-phase component and the quadrature component of the correlation value output from the correlation calculation unit 105 at a predetermined time interval, and obtains the delay profile. Generate. The section for generating the delay profile has a section length equal to the basic midamble code length (128 chips in 3GPP TS25.221). The generated delay profile is output to the path position detection unit 202.

  The path position detection unit 202 divides the delay profile output from the delay profile generation unit 201 into user windows corresponding to the unit midamble shift amount W, expands each user window by t chips before and after, and further expands the first half of the expanded window. Minutes are used as leading windows, and the latter half are used as rear windows, and peaks of a predetermined value or more appearing in each preceding window and each rear window are detected as paths of signals transmitted from users corresponding to the windows. The detected path position is output to the despreading unit 203 and the power calculation unit 204, and the correlation value power of the detected path is output to the power calculation unit 205.

  The despreading unit 203 despreads the received BB signal output from the A / D conversion unit 103 using the channelization code output from the channelization code generation unit 106 at the path position output from the path position detection unit 202. I do. Specifically, one slot of the received BB signal is composed of a first data part and a second data part with the midamble part interposed therebetween, and attention is paid to the slot including the midamble part used in the correlation calculation part 105. To do. In the case of despreading at the path position detected in the preceding window, despreading is performed for a predetermined chip at the beginning of the first data portion using the channelization code assigned to the user corresponding to the user window included in the preceding window. . On the other hand, when despreading is performed at the path position detected in the rear window, a predetermined chip portion at the end of the second data portion is obtained using a channelization code assigned to the user corresponding to the user window included in the rear window. Despread. Here, the predetermined chip portion of the data part to be despread is a chip length corresponding to one symbol, and this differs depending on the spreading factor of the channelization code. The result obtained by the despreading unit 203 is output to the power calculation unit 204.

  The power calculation unit 204 calculates the power Ps per chip from the despreading result for each one symbol of the first data unit and the second data unit output from the despreading unit 203. A specific method for calculating the power Ps is that the despreading in the despreading unit 203 is performed by summing the result of multiplying one symbol of the data part by the channelization code of the spreading factor SF for each chip. The power Ps per chip is calculated by dividing the square sum of the orthogonal components by the spreading factor SF. The calculated power Ps is output to the power ratio calculation unit 206.

  The power calculation unit 205 calculates the power Pd per chip by dividing the correlation value power of the peak detected as a path by the path position detection unit 202 by the basic midamble code length, and the calculated power Pd is the power ratio. It outputs to the calculation part 206.

  The power ratio calculation unit 206 calculates the power ratio Ps / Pd of the power Ps output from the power calculation unit 204 with respect to the power Pd output from the power calculation unit 205. As a result, it is not necessary to consider fluctuations associated with the power Ps and the power Pd depending on the reception state for each path, and the influence of the reception state can be eliminated. The calculated power ratio Ps / Pd is output to the validity determination unit 207.

  The validity determination unit 207 performs threshold determination between the power ratio Ps / Pd output from the power ratio calculation unit 206 and a predetermined threshold Th. If the threshold is equal to or greater than the threshold Th, the detected path is a user corresponding to the user window. If it is determined that the path is a path of the signal transmitted from the user (effective path) and is less than the threshold Th, it is determined that the detected path is not a path of the signal transmitted from the user corresponding to the user window (invalid path). The predetermined threshold Th can be changed based on the state of the propagation path represented by an index such as SIR (Signal to Interference Ratio). The path position of the path determined to be valid by the validity determination unit 207 is output to the demodulation unit 108.

  Next, the despreading target in the despreading unit 203 will be described with reference to the drawings. FIG. 3 is a schematic diagram showing the relationship between the path positions detected in the preceding window and the rear window and the data part to be despread. As shown in this figure, the user window has a window width W, is enlarged by t chips before and after the user window, the front half of the enlarged window is a leading window (window width W / 2 + t), and the rear half is a rear window. (Window width W / 2 + t). Here, the reason for expanding t chips before and after the user window is that the path near the boundary of the user window is likely to be a path beyond the window, and is a path corresponding to the user window M or an adjacent user window. This is because it is necessary to confirm whether the path corresponds to M−1 and M + 1.

  Further, this figure shows a case where the path position detected in the preceding window and the path position detected in the rear window are shifted by the window width W chips. Hereinafter, it is assumed that the paths detected in the preceding window and the rear window are paths of signals transmitted from the user M, and are processed as a path of a preceding wave and a path of a delayed wave, respectively.

  Since the path positions of the preceding wave and the delayed wave are shifted by W chips, the head of each slot is also shifted by W chips. FIG. 3 shows a case where the head of the second symbol of the preceding wave and the head of the first symbol of the delayed wave have the same timing. Here, when the despreading unit 203 performs despreading using the channelization code assigned to the user M from the slot head (first data portion head) using each path position, the preceding wave and the delayed wave are intersymbol-coded. Interference occurs and it becomes impossible to determine at which path position the despreading is performed. In particular, when the difference between the preceding wave and the delayed wave is equal to the spreading code length of the data part, a large interference occurs, and it becomes impossible to determine which despreading result is obtained.

  Therefore, when despreading at the path position detected in the preceding window, one symbol at the head of the first data portion of the preceding wave is despread, and when despreading at the path position detected in the rear window, One symbol at the end of the second data portion of the delayed wave is despread. This eliminates the part of the delayed wave that interferes with the target of despreading the preceding wave, and also eliminates the part of the preceding wave that interferes with the target of despreading the delayed wave. It can be determined whether there is.

  Here, the reason why large interference occurs when the difference between the preceding wave and the delayed wave is equal to the spreading code length of the data portion will be described. The data part is multiplied by a channelization code unique to each mobile station and a cell-specific scrambling code. The channelization code has a variable spreading factor, and the scrambling code has a fixed spreading factor (16 times here). ).

  FIG. 4 is a diagram for explaining a code pattern when the spreading factor of the channelization code is 16 times. In this figure, the code patterns of channelization codes are shown as 1 to 16, and the code patterns of scrambling codes are shown as A to P. The multiplication of the channelization code and the scrambling code means that the code patterns 1 to 16 of the channelization code and the scrambling codes A to P are multiplied. For example, a channelization code (hereinafter abbreviated as “CC”) 1 and a scrambling code (hereinafter abbreviated as “SC”) A are multiplied, and the multiplied spreading code is represented by (1, A). Similarly, CC2 and SCB are multiplied to obtain a spreading code (2, B). Thus, the code pattern obtained by multiplying the channelization code and the scrambling code is a 16-chip repetitive pattern of (1, A) to (16, P). In this case, if a delay of one symbol occurs, the spreading rate of the channelization code is 16 times, so that the preceding wave and the delayed wave are shifted by 16 chips, and the spreading code sequence of the preceding wave and the delayed wave (channelization code) And the scrambling code multiplied code sequence) are the same at the same timing. For this reason, the preceding wave and the delayed wave cause large intersymbol interference with each other.

  FIG. 5 is a diagram for explaining a code pattern when the spreading factor of the channelization code is 8 times. In this figure, the code patterns of channelization codes are shown as 1 to 8, and the code patterns of scrambling codes are shown as A to P. The code pattern obtained by multiplying the channelization code and the scrambling code is a 16-chip repetitive pattern of (1, A) to (8, H) and (1, I) to (8, P). In this case, if a delay of one symbol occurs, since the spreading factor of the channelization code is 8 times, the preceding wave and the delayed wave are shifted by 8 chips, and the spreading code sequences of the preceding wave and the delayed wave are the same. The spreading code is also different at the timing. For example, the spreading code (1, I) of the preceding wave and the delayed wave (1, A) have the same timing, and the interference between the preceding wave and the delayed wave is reduced. However, if a delay of 2 symbols occurs, the spreading code sequences of the preceding wave and the delayed wave are the same at the same timing. For this reason, the preceding wave and the delayed wave cause large intersymbol interference with each other.

  FIG. 6 is a diagram for explaining a code pattern when the spreading factor of the channelization code is four times. In this figure, the code patterns of the channelization codes are shown as 1 to 4, and the code patterns of the scrambling codes are shown as A to P. The code patterns obtained by multiplying the channelization code and the scrambling code are (1, A) to (4, D), (1, E) to (4, H), and (1, I) to ( 4, L) and 16 chips of (1, M) to (4, P). In this case, if a delay of one symbol occurs, the spreading factor of the channelization code is four times, so that the preceding wave and the delayed wave are shifted by 4 chips, and the spreading code sequences of the preceding wave and the delayed wave are the same. The spreading code is also different at the timing. For example, the spreading code (1, E) of the preceding wave and the delayed wave (1, A) have the same timing, and the interference between the preceding wave and the delayed wave is reduced. However, if a delay of 4 symbols occurs, the spreading code sequences of the preceding wave and the delayed wave are the same at the same timing. For this reason, the preceding wave and the delayed wave cause large intersymbol interference with each other.

  Thus, even if the spreading factors of the channelization codes are different, if there is a deviation of 16 chips (precisely 16 × N chips, where N is a positive number) between the preceding wave and the delayed wave, the preceding wave and the delayed wave Will be the same spreading code at the same timing and will have a large interference with each other. Even in such a case, the first data portion head and the second data portion tail will be subject to despreading to cause a large interference with each other. It can be avoided to fit.

  Next, the reason why the user window is divided into the preceding window and the rear window will be described. In general, the window width W = 32 is a practical window width for the user window, and as described above, there is a case where a deviation of 16 chips occurs in the preceding wave and the delayed wave in one user window. For this reason, by dividing the user window in half and using the preceding window and the rear window, the path of the preceding wave and the delayed wave having a deviation of 16 chips in the preceding window or the rear window does not appear. Then, the despreading target of the data part using the path position detected in the preceding window is set as one symbol at the head of the first data part, and the despreading target of the data part using the path position detected in the rear window is set to the second. By designating it as one symbol at the end of the data portion, it is possible to determine which despreading result uses which path position even if a 16-chip shift occurs between the preceding wave and the delayed wave.

  However, when the user window has window widths W = 32 and W = 64, the following problem must be dealt with. That is, since the user window is enlarged by t chips back and forth, when the user window has a window width W = 32, the window width of the preceding window (or rear window) is 16 + t, and when the user window has a window width W = 64, The window width of the preceding window (or the rear window) is 32 + t, and there is a possibility that both the preceding wave and the delayed wave having a deviation of 16 chips are detected in one window. For this reason, as shown in FIG. 7, areas for B chips are provided from the boundary between the preceding window and the rear window, and the path detected in this area is unconditionally determined to be a valid path. B is defined by the following equation.

B = (W−SFmax × 2) / 2 + t (2)
W represents the window width, and SFmax represents the spreading code length. Thus, when the window width W is 32 or 64, the path detected in the area of B chips from the boundary between the preceding window and the rear window to the respective windows is hardly a path beyond the window, and the user concerned Since it is considered to be a path of a signal transmitted from the user corresponding to the window, the path detected in this area may be unconditionally determined as an effective path.

  Next, the operation of the user determination unit 107 will be described. The delay profile generation unit 201 continuously obtains the sum of squares of the in-phase component and the quadrature component of the correlation value output from the correlation calculation unit 105 at a predetermined time interval, and generates a delay profile. The generated delay profile is output to the path position detection unit 202.

The path position detection unit 202 detects a peak of a predetermined value or more appearing in the preceding window and the rear window as a path of a signal transmitted from the user corresponding to the window. Here, the path detected in the preceding window is referred to as path P _th1, and the path detected in the rear window is referred to as path P _th2 .

When despreading is performed at the path position of the path P _th1 detected in the preceding window, the despreading unit 203 uses the channelization code assigned to the user corresponding to the user window included in the preceding window to generate the first data Despread one symbol at the head of the copy. On the other hand, when despreading is performed at the path position of the path P _th2 detected in the rear window, the channelization code assigned to the user corresponding to the user window included in the rear window is used to determine the end of the second data portion. One symbol is despread.

The power calculation unit 204 calculates the power Ps per chip from the despreading result for each symbol of the first data portion and the second data portion output from the despreading unit 203, and the power calculation unit 205 determines the path P The power Pd per chip is calculated by dividing the correlation value power of _th 1 and path P _th 2 by the basic midamble code length.

In the power ratio calculation unit 206, for the path P _th1 detected in the preceding window, the power ratio Ps / Pd of the despread power Ps of the first data part with respect to the power Pd per chip calculated from the correlation value power of the delay profile Is calculated. Further, for the path P _th2 detected in the rear window, the power ratio Ps / Pd of the despread power Ps of the second data part to the power Pd per chip calculated from the received power of the delay profile is calculated.

The validity determination unit 207 performs threshold determination between the power ratio Ps / Pd and the predetermined threshold Th for the path P _th1 output from the power ratio calculation unit 206. If Ps / Pd is equal to or greater than the threshold Th, the pass P _th1 is determined to be a path of a signal transmitted from the user M (effective path), and if Ps / Pd is less than the threshold Th, it is determined not to be a path of a signal transmitted from the user M (invalid path). To do. Similarly, it is determined whether or not the path is an effective path from the power ratio Ps / Pd for the path P _th2 output from the power ratio calculation unit 206. Here, the path P _th1 is a path of a signal transmitted from the user M, and the path P _th2 is a path of a signal transmitted from the user M + 1. That is, if the path P _th2 is not a delayed wave path, the path P _th1 is determined to be a valid path, and the path P _th2 is determined to be an invalid path. This is because the path P _th2 is a path of a signal transmitted from the user M + 1, so that even if the second data portion is despread with the channelization code of the user M using the path position of the path P _th2 , the second data This is because the correlation between the partial spreading code sequence and the channelization code of the user M is low, the power Ps after despreading is low, and the power ratio Ps / Pd is less than the threshold Th.

Since the path P _th2 is detected in an area obtained by enlarging the user window backward by t chips, the path P _th2 is detected in the preceding window of the adjacent user window M + 1, and the same process as the process performed for the user window M is performed. The path P _th2 is determined to be a path of a signal transmitted from the user M + 1 (effective path).

  As described above, according to the present embodiment, the user window obtained by dividing the delay profile by the unit midamble shift amount W is enlarged by a predetermined amount in the front and rear, and the front half of the enlarged window is the leading window and the rear half is the rear window. The second data part using the despreading result at the head of the first data part detected by detecting a peak of a predetermined value or more as a path and despreading at the path position detected by the preceding window and the path position detected by the rear window The last despreading result is expressed in power per unit according to the reception state, and by determining a predetermined threshold value and a threshold value, respectively, even when a plurality of paths with an interval of 16 chips are detected in one user window Therefore, the user determination of each path can be performed with high accuracy, and it can be determined whether the path is for the user to be determined by the user or the path beyond the window.

(Embodiment 2)
In the first embodiment, when performing user determination, the target to be despread at the path position detected in the preceding window is only one symbol at the head of the first data portion, and despread is performed at the path position detected in the rear window. Although the case where the target is only one symbol at the end of the second data part has been described, in the second embodiment of the present invention, the case where the target to be despread at the path position detected in each window is a plurality of symbols is described. To do.

  However, since the configuration of the base station apparatus according to Embodiment 2 of the present invention is the same as that of FIGS. 1 and 2 shown in Embodiment 1, FIG. 1 and FIG. 2 are used and detailed description thereof is omitted. .

  FIG. 8 is a schematic diagram showing the relationship between the path positions detected in the preceding window and the rear window and the data part to be despread. As shown in this figure, the despreading unit 203 despreads the first symbol of the first data portion and the first symbol of the second data portion using the path position detected in the preceding window. The despreading unit 203 despreads the last symbol of the first data part and the last symbol of the second data part using the path position detected in the rear window.

  Here, unlike the first embodiment, the addition of the first symbol at the head of the second data part for the object to be despread at the path position detected in the preceding window is that the delayed wave at the same timing as this symbol is It becomes the midamble part. Since the data part and the midamble part have low correlation, they do not interfere strongly with each other. Similarly, the reason why the last symbol of the first data portion is added as a target to be despread at the path position detected in the rear window is that the preceding wave at the same timing as this symbol becomes the midamble portion. It is.

  The power calculation unit 204 calculates the power per chip from the despreading result of each one symbol at the head of the first data portion and the head of the second data portion despread at the path position detected in the preceding window, and calculates the calculated power Add to get power Ps. Thereby, since the symbol gain is improved, noise can be reduced. As a result, effective path determination (user determination) can be performed with high accuracy.

  As described above, according to the present embodiment, the object to be despread at the path position detected in the preceding window is set to one symbol at the head of the first data portion and the head of the second data portion, and the path position detected at the rear window. Since the symbol to be despread in 1st each of the first data part and the second data part at the end of the user determination, the symbol gain can be improved and the noise can be reduced. It can be performed with high accuracy.

  It should be noted that whether or not the last symbol of the first data portion and the first symbol of the second data portion are to be despread is determined based on reception quality such as SIR indicating the accuracy of the symbol. Good.

(Embodiment 3)
In the first and second embodiments, the user determination is performed based on whether or not the power ratio in each path exceeds a predetermined threshold. However, in the third embodiment of the present invention, the user determination is performed according to the power ratio in each path. A case where the weight is expressed by the following will be described.

  FIG. 9 is a block diagram showing the configuration of the base station apparatus according to Embodiment 3 of the present invention. However, the parts in FIG. 9 that are the same as those in FIG. 1 are given the same reference numerals as those in FIG. 9 differs from FIG. 1 in that the user determination unit 107 is changed to a user determination unit 901, and the demodulation unit 108 is changed to a demodulation unit 902.

  The user determination unit 901 generates a delay profile based on the correlation value output from the correlation calculation unit 105, and detects a peak greater than a predetermined value from the delay profile divided by the unit midamble shift amount W as a path. Then, the user determination unit 901 uses the channelization code output from the channelization code generation unit 106 for the portion corresponding to the position where the peak appears in the data portion of the received BB signal output from the A / D conversion unit 103. Use despreading. Further, user determination section 901 calculates the power ratio between the power per chip of the signal after despreading and the power per peak peak in the delay profile, and outputs the calculated power ratio to demodulation section 902. The detected path position is also output to the demodulator 902.

  Demodulation section 902 adds a weight obtained by converting the power ratio output from user determination section 901 to the channel estimation value (correlation value) output from correlation calculation section 105. Also, the data portion of the received BB signal output from the A / D conversion unit 103 is despread using the path position output from the user determination unit 901 and the channelization code output from the channelization code generation unit 106. . Using the weighted channel estimation value, the despread data part is RAKE combined, JD (Joint Detection) calculation is performed, and the demodulation result is output.

  FIG. 10 is a block diagram showing an internal configuration of the user determination unit 901 according to Embodiment 3 of the present invention. However, the parts in FIG. 10 that are the same as those in FIG. 2 are given the same reference numerals as those in FIG. 10 is different from FIG. 2 in that the validity determination unit 207 is deleted.

  The power ratio calculation unit 206 outputs the power ratio Ps / Pd of the power Ps calculated by the power calculation unit 204 to the power Pd calculated by the power calculation unit 205 to the demodulation unit 902.

  FIG. 11 is a block diagram showing an internal configuration of demodulation section 902 according to Embodiment 3 of the present invention. In this figure, the weight conversion unit 1101 converts the power ratio output from the user determination unit 901 into a weight, and outputs the weight to the multiplication unit 1102. The weight conversion unit 1101 has a function defined in advance by a power ratio and a weight, and the power ratio is converted into a weight by this function.

  Multiplication section 1102 multiplies the channel estimation value output from correlation calculation section 105 by the weight output from weight conversion section 1101, and outputs the weighted channel estimation value to RAKE combining section 1104 and JD calculation section 1105. .

  Despreading section 1103 despreads the data part of the received BB signal using the channelization code at the path position output from user determination section 901, and outputs the despread signal to RAKE combining section 1104.

  The RAKE combining unit 1104 multiplies the weighted channel estimation value and the despread signal for each path, and RAKE combines the multiplication results. The RAKE synthesis result is output to the JD calculation unit 1105. A JD operation unit 1105 performs a predetermined matrix operation using a system matrix in which a path detection result for each mobile station and a convolution operation result of a channelization code are arranged in a matrix, and a data unit obtained by despreading the matrix operation result By multiplying by, the demodulation result from which interference is removed is output.

  Next, a function defined by the power ratio and weight of the weight conversion unit 1101 will be described. FIG. 12 is a diagram illustrating a function of the weight conversion unit 1101. In this figure, a weight of 1.0 corresponds to the effective path described in the first embodiment, and a weight of 0 indicates the first embodiment. This corresponds to the invalid path described in. FIG. 12A shows a function in which the power ratio and the weight are in a proportional relationship. That is, when the function shown in this figure is used, the value of the power ratio becomes the weight as it is. This is suitable when the reception state is good. FIG. 12B shows a function having a steep slope near the threshold. In this figure, the weight is approximately 1.0 from a power ratio of 1.0 to a threshold (for example, a power ratio of 0.8), and the weight is drastically decreased below the threshold. This is suitable when the reception state is poor. The weight converter 1101 may have either the function shown in FIG. 12A or the function shown in FIG. 12B, or may have any function and use any function. Good. Further, the two functions may be switched and used according to the reception state.

  When the window width W is equal to or greater than twice the spreading code length SFmax, as in the case of the window widths W = 32 and W = 64, the weight conversion unit 1101 is B chips worth from the boundary between the preceding window and the rear window. The path detected in this area is unconditionally given a weight of 1.0.

  As described above, according to the present embodiment, by representing the user determination by the weight according to the power ratio, the weighting value is increased for the path from the user corresponding to the user window targeted for the user determination. For the paths that have passed, the weighting value becomes smaller, and the demodulation accuracy can be improved by RAKE-combining the data part signals despread for each path reflecting these weightings.

  As shown in FIG. 13, the RAKE combining method weights the channel estimation value for each finger (for each path), multiplies the weighted channel estimation value by the despread value, and obtains fingers # 1 to # 1. As shown in FIG. 14, the despread value is multiplied by the channel estimation value for each finger, the multiplication result is weighted, and the fingers # 1 to #N are synthesized. Also good.

(Other embodiments)
The configuration of a base station apparatus according to another embodiment of the present invention is the same as that shown in FIGS. 1 and 2, and will be described with reference to FIGS. The path detected in the area for t chips before and after the boundary of the user window is determined for each user window, but the power ratio obtained for one user window and the other user window are obtained. If both of the power ratios are less than the predetermined threshold and are invalid paths, the validity determination unit 207 compares the power ratios and determines that the path is for the user with the larger power ratio.

  Thereby, there is a high possibility that the path detected in the vicinity of the boundary with the adjacent user window is a path beyond the window, but the user can be surely determined even if the path is beyond the window.

  In addition, without comparing the power ratio obtained for both user windows with a predetermined threshold, the power ratios of both are compared, and the path of the user with the larger power ratio is determined. Good.

  In each of the above-described embodiments, the case where the base station apparatus performs user determination has been described. However, the present invention is not limited to this, and the mobile station apparatus may perform user determination.

  The radio reception apparatus and radio reception method according to the present invention can be applied to a base station apparatus that removes an interference component from a received signal based on a path detection result.

The block diagram which shows the structure of the base station apparatus which concerns on Embodiment 1, 2 of this invention, and other embodiment. The block diagram which shows the internal structure of the user determination part which concerns on Embodiment 1, 2 and other embodiment of this invention. Schematic diagram showing the relationship between the path position detected in the preceding window and the rear window and the data part to be despread The figure which uses for the description of the code pattern in case the spreading factor of a channelization code is 16 times The figure which uses for the explanation of the code pattern when the spreading factor of the channelization code is 8 times The figure used for description of the code pattern when the spreading factor of the channelization code is 4 times The figure which shows the front window and back window when a window width becomes 2 times or more of the spreading code length of a data part Schematic diagram showing the relationship between the path position detected in the preceding window and the rear window and the data part to be despread The block diagram which shows the structure of the base station apparatus which concerns on Embodiment 3 of this invention. The block diagram which shows the internal structure of the user determination part which concerns on Embodiment 3 of this invention. The block diagram which shows the internal structure of the demodulation part which concerns on Embodiment 3 of this invention. The figure which shows the function which a weight conversion part has Diagram showing RAKE synthesis method Diagram showing RAKE synthesis method The figure which shows the mode of the mobile communication system containing the base station provided with the interference removal apparatus The figure which shows the structure of the frame format and slot format of a TD-SCDMA system Schematic diagram illustrating a method for generating a midamble code by the base station BS Diagram for explaining the delay profile and user window generated by the base station The figure which shows the delay profile after the path restriction | limiting produced | generated in a base station

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Antenna 102 Radio | wireless part 103 A / D conversion part 104 Pilot code sequence production | generation part 105 Correlation calculation part 106 Channelization code production | generation part 107,901 User determination part 108,902 Demodulation part 201 Delay profile generation part 202 Path position detection part 203, 1103 Despreading section 204, 205 Power calculation section 206 Power ratio calculation section 207 Validity determination section 1101 Weight conversion section 1102 Multiplication section 1104 RAKE combining section 1105 JD calculation section

Claims (14)

A radio that receives from the communication partner a signal in which the midamble part is multiplexed at the same time, with the midamble part unique to each mobile station formed by cyclically shifting the basic midamble code unique to the cell by the unit shift amount. A receiving device,
A delay profile generating means for generating a delay profile by taking a correlation while cyclically shifting the plurality of midamble parts included in a received signal and the basic midamble code unique to the cell prepared in advance;
The delay profile is divided by a user window having a window width corresponding to a unit shift amount of the basic midamble code, and a peak of a predetermined value or more appearing in each user window is used as a path of a signal transmitted from a communication partner. Path position detecting means for detecting the position of
Of the first data portion and the second data portion that are time-division multiplexed across the midamble portion, a predetermined portion corresponding to the path position that appears in the user window is assigned to the user corresponding to the user window. Despreading means for despreading at the path position using a channelization code,
A determination means for determining whether or not a path obtained by despreading the data portion is a valid path based on the power of the despread data symbol;
A wireless receiver characterized by comprising: The path position detecting means includes
The position of the path is detected as a path of a signal transmitted from a communication partner with a peak of a predetermined value or more appearing in a window obtained by enlarging the window width of each user window by a predetermined amount before and after. The wireless receiving device described. The path position detecting means includes
The front half of each user window is the leading window, the rear half is the rear window, and the peak of a predetermined value or more appearing in the preceding window and the rear window is detected as the path of the signal transmitted from the communication partner. The wireless reception device according to claim 1 or 2, wherein the wireless reception device is a wireless communication device. The despreading means includes
The target to be despread at the path position detected in the preceding window is the first data portion head, and the target to be despread at the path position detected in the rear window is the second data portion tail. The wireless receiver according to claim 3. The despreading means includes
The target to be despread at the path position detected in the preceding window is the first data portion head and the second data portion head, and the target to be despread at the path position detected in the rear window is the first data portion. The wireless reception device according to claim 3, wherein the last data and the second data part are the last data. Comprising reception quality measuring means for measuring the reception quality of the received signal;
The despreading means includes
If the reception quality is equal to or higher than a predetermined value, the object to be despread at the path position detected in the preceding window is the first data portion head, and the object to be despread at the path position detected in the rear window is the If the reception quality is less than a predetermined value at the end of the second data portion, the target to be despread at the path position detected in the preceding window is the first data portion start and the second data portion start, The radio reception apparatus according to claim 3, wherein targets to be despread at a path position detected by a rear window are the tail of the first data portion and the tail of the second data portion. Power ratio calculating means for calculating a power ratio between the power of the peak of the delay profile and the power of the despread data portion;
The determination means includes
The radio reception apparatus according to any one of claims 1 to 6, wherein if the power ratio is equal to or greater than a predetermined value, a path at a path position obtained by despreading the data portion is determined as an effective path. . The determination means includes
When the window width of the user window is more than twice the spreading code length of the data part, the path detected in a predetermined chip area before and after the boundary between the preceding window and the rear window is an unconditionally effective path. The wireless receiver according to claim 3, wherein the wireless receiver is determined. The determination means includes
Corresponding to the power of the data part despread using the channelization code assigned to the user corresponding to one user window at the path position detected near the boundary with the adjacent user window and the other user window The size of the despread data part power is compared using the channelization code assigned to the user, and the user's path from which the large power is obtained is determined to be valid. The radio reception apparatus according to any one of claims 8 to 9. The determination means includes
Power of the data part despread using the channelization code assigned to the user corresponding to one user window at the path position detected near the boundary of the adjacent user window, and the user corresponding to the other user window If the power of the data part despread using the channelization code assigned to is less than a predetermined value and the path is determined to be an invalid path, the power of both is compared and the large power is The radio reception apparatus according to claim 1, wherein the obtained user path is determined to be valid. The determination means includes
9. The path according to claim 1, wherein a path at a path position where the data part is despread is a valid path with a weight corresponding to the power of the despread data part. Wireless receiver.   A base station apparatus comprising the radio reception apparatus according to any one of claims 1 to 11.   A mobile station apparatus comprising the radio reception apparatus according to any one of claims 1 to 11. A radio that receives from the communication partner a signal in which the midamble part is multiplexed at the same time, with the midamble part unique to each mobile station formed by cyclically shifting the basic midamble code unique to the cell by the unit shift amount. A receiving method,
A delay profile generating step for generating a delay profile by taking a correlation while cyclically shifting the plurality of midamble parts included in the received signal and the basic midamble code unique to the cell prepared in advance;
The delay profile is divided by a user window having a window width corresponding to a unit shift amount of the basic midamble code, and a peak of a predetermined value or more appearing in each user window is used as a path of a signal transmitted from a communication partner. A path position detecting step for detecting the position of
Of the first data portion and the second data portion that are time-division multiplexed across the midamble portion, a predetermined portion corresponding to the path position that appears in the user window is assigned to the user corresponding to the user window. A despreading step of despreading at the pass position using a channelization code;
A determination step of determining whether or not a path obtained by despreading the data portion is a valid path based on the power of the despread data symbol;
A wireless reception method comprising:

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