JP2005303952A - Geometry measuring method, radio receiving device and mobile station device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing, under a propagation environment where multipaths are formed, simply and easily a geometry for facilitating determining which is better to perform RAKE reception for reception signals or to perform adaptive reception by using an adaptive equalizer, an interference canceller or the like. <P>SOLUTION: Interference signal electric power contained in the receiving signal is measured for each path and the interference signal electric power measured for each path is totalized for N paths thereof. Further, interference signal electric power other than that of the paths contained in the receiving signals is measured and its own cell interference signal electric power is calculated by subtracting a total value determined by totalizing the interference signal electric powers of each path for the N paths from a value determined by multiplying the interference signal electric power other than that of the paths by N. Furthermore, a total electric power value of the other cell interference signals and noises is calculated by subtracting aforementioned its own cell interference signal electric power from the interference signal electric power other than that of the paths, thus calculating the geometry by dividing the its own cell interference signal electric power by the total electric power value of the other cell interference signals and noises. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a radio reception apparatus and a mobile station apparatus in a cellular radio communication system using HSDPA (High Speed Downlink Packet Access) and the like, and a geometry measurement method used in these apparatuses.

  As an access method in a mobile communication system, a W-CDMA (Wideband-Code Division Multiple Access) method has been standardized. In the W-CDMA system, introduction of HSDPA is being studied for the purpose of speeding up the downlink. In HSDPA, adaptive modulation is used in which the base station apparatus adaptively adjusts the modulation scheme and coding rate of the transmission signal according to the reception quality in the mobile station apparatus.

  In this adaptive modulation, when the reception quality in the mobile station apparatus is good, for example, the modulation method is 16QAM (Quadrature Amplitude Modulation) and the coding rate is ½, and the throughput is improved. In a poor case, for example, the modulation scheme is QPSK (Quadrature Phase Shift Keying) and the coding rate is 1/3, and the reception error rate is improved in exchange for a reduction in throughput. Thus, in order to improve throughput in adaptive modulation, a modulation scheme with a short distance between signals and a coding rate with low redundancy are used, so that the throughput is affected by interference signals and noise. It becomes easy to appear. Therefore, introduction of an adaptive equalizer and an interference canceller has been studied in adaptive modulation. The adaptive equalizer reduces the influence of the interference signal in the received signal by estimating the propagation path characteristics and equalizing the received signal by forming the inverse characteristics of the estimated propagation path characteristics in the received signal by the adaptive filter. To do. The interference canceller estimates the signal component that becomes an interference source and subtracts the component (interference signal) to reduce the influence of the interference signal in the received signal.

  In adaptive modulation, a desired signal power to interference power ratio, that is, a SIR (Signal to Interference Ratio) in a received signal is generally used as a measure for improving reception quality. As SIR measurement methods, there are an SIR measurement method after RAKE synthesis and an SIR measurement method before RAKE synthesis. In these methods, SIR is measured using a known symbol included in a received signal. Specifically, in the SIR measurement method after RAKE combining, the power of a known symbol included in the received signal after RAKE combining is measured, and the measured power of the known symbol is averaged to obtain a desired signal power (RSCP: Received Signal). Code Power) is calculated, variance is calculated from the desired signal power and the power of each known symbol, and this is used as interference signal power (ISCP), and the ratio of RSCP to ISCP is SIR. On the other hand, in the SIR measurement method before RAKE combining, a known symbol before RAKE combining is despread to obtain the despread value, and the average of the despread values and the variance of the despread values are calculated for each path. The sum of the despread average values for each path is set as desired signal power (RSCP), the calculated average value of dispersion for each path is set as interference signal power (ISCP), and the ratio of RSCP to ISCP is set as SIR.

Hereinafter, the SIR measurement method after RAKE synthesis will be described using mathematical expressions. First, the known symbols included in the received signal are despread to perform synchronous detection and RAKE combining. At this time, the synchronous detection coefficients h [p] .i and h [p] .q for each path are obtained by performing quadrant correction on the despread value for each symbol as shown in the following equations (1) and (2). Desired.

The components Rx [n] .i and Rx [n] .q of the power of the known symbol after RAKE combining are obtained by the following equations (3) and (4).

Next, RSCP is calculated. The RSCP measurement result rscp for each slot is obtained by the following formulas (5) and (6) as the average power of known symbols after RAKE combining.

Thereby, the measurement result of RSCP is calculated | required by following formula (7).

Next, ISCP is measured. The components Icp of iscp [n] .i and iscp [n] .q are obtained from Equation (8) and Equation (9) from the difference between the power of the known symbol after RAKE combining and the average for each slot. .

Thereby, ISCP for every slot is calculated | required by following formula (10).

Finally, SIR is calculated. SIR is calculated | required by following formula (11) and Formula (12) using RSCP and ISCP by Formula (7) and Formula (10).

Next, the SIR measurement method before RAKE synthesis will be described using mathematical expressions. Despread processing is performed on the known symbols included in the received signal, and quadrant correction is performed on the power of the known symbols after the despread processing. The components Sx [n] [p] .i and Sx [n] [p] .q (n = 1 to N) of the power of the known symbol after the quadrant correction of each path are expressed by the following equations (13) and ( 14).

Next, the RSCP is measured for the known symbol after quadrant correction. For the known symbol after quadrant correction, rscp [p] .i and rscp [p] .q, which are the average of each component of the power, are obtained by the following equations (15) and (16).

Thereby, RSCP for every path | pass is calculated | required by following formula (17).

And the whole RSCP is calculated | required by adding RSCP measurement electric power for every path | pass like following formula (18).

On the other hand, each component of the ISCP is obtained from the difference between the power of the known symbol after quadrant correction and the average for each slot (RSCP for each path). That is, iscp [n] [p] .i and iscp [n] [p] .q which are each component of the ISCP are obtained by the following equations (19) and (20).

Then, the ISCP for each path is obtained by averaging over a plurality of slots as in the following equation (21).

Further, as shown in the following formula (22), the total ISCP is obtained by dividing the total ISCP including the ISCP for each path by the number of paths.

  Finally, SIR is calculated. The SIR is obtained by the above formula (11) and formula (12) using the entire RSCP and the entire ISCP.

By the way, in the cellular radio communication system, the ratio of the desired signal power and the interference signal power included in the received signal differs depending on the position of the radio receiving apparatus such as a mobile station apparatus. Such a parameter that changes in accordance with the position of the wireless reception apparatus is sometimes called a geometry in the W-CDMA system (see Non-Patent Document 1). Note that the power of noise contained in the received signal is almost stable regardless of the position of the radio receiving apparatus.
Supervised by Keiji Tachikawa, “W-CDMA mobile communication system”, published by Maruzensha, June 25, 2001, p. 192-193

  However, when an adaptive equalizer or interference canceller is introduced, the interference reduction effect is generally large when the own cell interference is large. On the other hand, when interference or noise from other cells is large, a channel estimation error or interference signal In some cases, the estimation error is increased and the reception performance deteriorates. Therefore, it is preferable to perform reception using an adaptive equalizer or interference canceller when the own cell interference is large, and to perform conventional RAKE reception when interference or noise from other cells is large. However, in the conventional SIR measurement method, for example, when the ISCP is large and the reception quality is low, whether the ISCP is due to interference from the own cell (multipath interference), interference from other cells, noise (thermal noise), etc. It is not possible to distinguish between the two. That is, in the conventional SIR measurement method, there is a problem that it is not possible to determine whether it is better to perform RAKE reception or to use an adaptive equalizer or an interference canceller.

  In addition, in HSDPA in the W-CDMA system, in order to perform adaptive modulation, the mobile station apparatus needs to report reception quality (SIR equivalent value, for example, CQI: Channel Quality Indicator) to the base station apparatus in advance. However, there is a difference in reception performance between the case where the conventional RAKE reception is performed and the case where the adaptive equalizer and the interference canceller are used, so that the reception quality (SIR equivalent value) is also different. Become. Therefore, when the reception method is changed according to the propagation environment as described above, that is, when the RAKE reception and the adaptive equalizer or interference canceller are switched, the reception quality by the RAKE reception and the adaptive equalizer or interference canceller are used. It is not possible to determine from the SIR measurement result which transmission quality is preferred to be transmitted. Therefore, adaptive modulation may not function effectively in the HSDPA in the conventional W-CDMA system.

  Therefore, even when the mobile station apparatus always uses reception quality that assumes RAKE reception, that is, an adaptive equalizer or the like, it is conceivable to transmit reception quality that has undergone adaptive reception after RAKE combining to the base station apparatus. However, in that case, the reception quality transmitted to the base station apparatus becomes excessive quality. When such excessive quality reception quality is transmitted from the mobile station device to the base station device, system resources such as the transmission power of the base station device are excessively consumed, and the system capacity is adversely affected. The mobile station apparatus is obligated to report necessary and sufficient reception quality to the base station apparatus. In addition, even if it can be determined which reception quality the mobile station apparatus should transmit to the base station apparatus, the mobile station apparatus can use an adaptive equalizer or the like for reception quality report to the base station apparatus. There is a problem that power consumption of the mobile station apparatus increases because it is necessary to operate separately.

  The present invention has been made in view of the above points, and in a radio reception apparatus, it is better to perform RAKE reception on a received signal, or adaptive reception is performed using an adaptive equalizer, an interference canceller, or the like. A parameter for facilitating the determination, that is, a geometry measurement method that can easily generate a geometry in a propagation environment where multipaths are formed, and a radio with low power consumption that can effectively function adaptive modulation It is an object to provide a receiving apparatus and a mobile station apparatus.

  A geometry measurement method according to the present invention is a geometry measurement method used by a radio reception apparatus in a cellular radio communication system, and measures an interference signal power measurement step for measuring the power of an interference signal included in a reception signal for each path. A step of adding the measured interference signal power for each path for N paths, a step of measuring the interference signal power level other than the path for measuring the power of the interference signal other than the path included in the received signal, An own cell interference signal power calculating step of calculating own cell interference signal power by subtracting a summation result in the summing step from a value obtained by multiplying interference signal power other than the path by N, and a measured interference signal other than the path By subtracting the own cell interference signal power calculated from the power, the sum of the power of other cell interference signals and noise Geometry calculation for calculating a geometry by dividing the calculated other cell interference signal / noise power and calculating the own cell interference signal power by the calculated power of the other cell interference signal and noise. Steps.

  According to this method, since the geometry is calculated based only on the power measurement value of the received signal, the geometry can be easily generated even in a propagation environment where a multipath is formed.

  A radio receiving apparatus according to the present invention is a radio receiving apparatus in a cellular radio communication system, measures the power of an interference signal included in a received signal for each path, and measures the measured interference signal power for each path to N. The sum of the paths is obtained by measuring the power of the interference signal other than the path included in the received signal, and adding the interference signal power for each path by the N path from the value obtained by multiplying the interference signal power other than the path by N. Subtracting the self-cell interference signal power, subtracting the self-cell interference signal power from the interference signal power other than the path to calculate the sum of the power of the other-cell interference signal and noise, A configuration is adopted that includes geometry calculation means for calculating the geometry by dividing the interference signal power by the sum of the power of the interference signal of the other cells and the noise.

  According to this configuration, since the geometry calculation means for generating the geometry based only on the power measurement value of the received signal is provided, the power from the own cell is separated from the power and noise from other cells with a simple configuration. be able to.

  The radio reception apparatus according to the present invention is the radio reception apparatus according to the present invention, wherein in the invention, a reception method determination unit that determines a reception method for the received signal based on the geometry calculated by the geometry calculation unit, and a reception determined by the reception method determination unit And a received signal processing means for processing the received signal in a system.

  According to this configuration, in addition to the effect of the invention, since the reception method of the received signal is determined based on the calculated geometry, it is possible to select the optimal reception method regardless of the propagation environment, Reception quality can be improved.

  The radio reception apparatus according to the present invention further comprises estimation means for estimating a ratio of desired signal power occupying the total transmission power of the base station in the invention, wherein the reception method determination means includes the estimation result by the estimation means and the estimation result A configuration is adopted in which a receiving method for the received signal is determined based on the geometry calculated by the geometry calculating means.

  According to this configuration, in addition to the effect of the present invention, since the estimation unit that estimates the ratio of the desired signal power to the total transmission power of the base station is provided, the optimum signal is obtained regardless of the absolute amount of the transmission power of the desired signal. A proper reception method can be selected, and the reception quality can be improved.

  The radio reception apparatus according to the present invention includes, in the above invention, a reception quality measurement unit that measures reception quality of the reception signal, an interference amount calculation unit that calculates a multipath interference amount in the reception signal, and the geometry calculation unit. According to the calculated geometry and the calculated multipath interference amount, a configuration is provided that includes conversion means for converting the measured reception quality into reception quality after adaptive reception.

  According to this configuration, in addition to the effects of the present invention, the reception quality of the received signal after RAKE combining is converted into the reception quality after adaptive reception according to the propagation environment by the conversion means. It is not necessary to separately operate an adaptive equalizer or the like for reporting, and highly accurate reception quality reporting can be performed while suppressing power consumption.

  The mobile station apparatus according to the present invention employs a configuration including the radio receiving apparatus according to the present invention.

  According to this configuration, in addition to the effects of the present invention, an optimal reception scheme can be selected with a simple configuration regardless of the propagation environment, so that reception quality can be improved while suppressing power consumption.

  According to the present invention, since the geometry is calculated based only on the power measurement value of the received signal, the power from the own cell and the power and noise from other cells can be separated with a simple configuration, and as a result, Regardless of the propagation environment, it is possible to improve the reception quality while suppressing the power consumption in the wireless receiver.

  The essence of the present invention is to estimate the effect of adaptive reception by an adaptive equalizer, interference canceller, etc. by calculating a geometry based only on the power measurement value of a received signal in a propagation environment where a multipath is formed. It is.

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

(Embodiment 1)
FIG. 1 shows an example of a received signal delay profile in a cellular radio communication system. It is assumed that N paths are formed in this received signal. In FIG. 1, the path formed in the received signal is represented as a peak of the delay profile. FIG. 1 also shows desired signal powers RSCP ₁ to ₃ and interference signal powers ISCP ₁ to 3 that constitute three characteristic peaks 1 to 3 of the delay profile. Since FIG. 1 is represented by a delay profile, noise is not included in the components of the peaks 1 to 3 of the delay profile. Further, the timing of ISCP _{N +} 1 in FIG. 1 corresponds to a phase other than the path of the received signal.

  Hereinafter, the geometry measurement method according to the present invention will be described using mathematical expressions, taking as an example the case where the delay profile of the received signal is FIG. In this embodiment, it is assumed that wireless communication by the W-CDMA method is performed.

When the total received power of the i-th path in the received signal is Pi, components included in ISCP are expressed as follows. Note that iscp [i] is the ISCP for each path obtained by the equation (21). SF indicates the diffusion rate.
iscp [1] = (1 / SF) x {sum of other cell interference + noise + (sum of own cell interference-P1)}
iscp [2] = (1 / SF) x {sum of other cell interference + noise + (sum of own cell interference-P2)}
...
iscp [N] = (1 / SF) x {sum of other cell interference + noise + (sum of own cell interference-PN)}

Assuming that the total of these N paths is ISCP _all , ISCP _all is expressed as follows.
ISCP _all = (N / SF) x (sum of other cell interference + noise) + (N / SF) x sum of own cell interference-(Pl + P2… + PN)
= (N / SF) x (sum of other cell interference + noise) + {(N-1) / SF} x sum of own cell interference

On the other hand, the ISCP measured at a phase other than the path is expressed as follows.
ISCP _{N + 1} = (1 / SF) x (sum of other cell interference + noise + sum of own cell interference)

By using these calculation results as follows, the total sum of the own cell interference power can be obtained.
N ・ ISCP _{N + 1} -ISCP _all = (1 / SF) x Sum of own cell interference Sum of own cell interference = SF (N ・ ISCP _{N + 1} -ISCP _all )

Therefore, (other cell interference + noise) can also be obtained as follows.
ISCP _{N + 1} -1 / SF · total sum of own cell interference = 1 / SF · (sum of other cell interference + noise)
(Sum of other cell interference + Noise) = SF / ISCP _{N + 1-} Sum of own cell interference
= SF ・ {ISCP _all + (N-1) ISCP _{N + 1} }

As a result, the geometry is expressed by the following equation.
Geometry = total cell interference / (total other cell interference + noise)
= (N ・ ISCP _{N + 1} -ISCP _all ) / {ISCP _all + (N-1) ISCP _{N + 1} }

  Moreover, the measurement timing of each ISCP and RSCP must be aligned. This is because if the measurement timing is different, the transmission power of the own cell and other cells changes, and ISCP and RSCP cannot be obtained correctly.

Instead of ISCP _{N + 1} , the total received power measured at the input terminal of the wireless reception device may be used. In this case, it is not necessary to multiply ISCP _{N + 1} by the number of paths (N) in order to obtain the sum of the own cell interference.

  FIG. 2 is a block diagram showing a configuration of radio receiving apparatus 200 according to the present embodiment. The wireless reception device 200 is mounted and used in a mobile station device such as a mobile phone in a cellular wireless communication system.

  The wireless reception device 200 includes an antenna 201, a wireless reception unit 202, a path search unit 203, a plurality of despreading units 204, a geometry calculation unit 205, a reception method determination unit 206, a demodulation unit 207, and a decoding unit 208.

  Radio reception section 202 performs normal radio reception processing such as down-conversion on the signal received by antenna 201, and inputs the received signal after radio reception processing to path search section 203 and a plurality of despreading sections 204, respectively.

  The path search unit 203 creates a delay profile from the received signal input from the wireless reception unit 202, and selects the timing for despreading by detecting the peak of the delay profile. Then, the path search unit 203 notifies the plurality of despreading units 204 of the selected timings.

  The despreading unit 204 is provided for the number N of received signal paths, and operates when receiving a notification from the path search unit 203. The despreading unit 204 despreads the reception signal input from the wireless reception unit 202 at the timing notified from the path search unit 203, and the received signal after despreading is subjected to a geometry calculation unit 205 and a demodulation unit. Input to 207 respectively.

  The geometry calculation unit 205 calculates the geometry by performing the calculations shown in the above formulas (1) to (22) on the received signal input from the despreading unit 204. Then, the geometry calculation unit 205 inputs the calculated geometry to the reception method determination unit 206.

  The reception method determination unit 206 determines a reception method to be executed by the demodulation unit 207 by comparing the geometry input from the geometry calculation unit 205 with a predetermined threshold, and notifies the demodulation unit 207 of the determination result. . Specifically, if the geometry is equal to or greater than a predetermined threshold, the reception method determination unit 206 determines that the received signal does not contain much noise, and performs adaptive modulation by an adaptive equalizer or the like on the received signal. Instruct to do. On the other hand, if the geometry is less than the predetermined threshold, the reception method determination unit 206 determines that the received signal contains a lot of noise, and performs adaptive modulation by an adaptive equalizer or the like on the received signal. Instruct not to.

  The demodulating unit 207 includes a plurality of receiving circuits such as a RAKE receiver and an adaptive equalizer, and receives a received signal input from the despreading unit 204 according to an instruction from the receiving method determining unit 206. Input to the circuit. Demodulation section 207 demodulates the reception signal processed by the reception circuit, and then inputs the demodulated reception signal to decoding section 208. Therefore, the demodulator 207 functions as a received signal processing unit according to the present invention.

  The decoding unit 208 generates reception data by decoding the reception signal input from the demodulation unit 207, and inputs the generated reception data to a baseband unit (not shown).

  As described above, according to the present embodiment, since the geometry is calculated based only on the power measurement value of the received signal, the geometry can be easily generated even in a propagation environment where a multipath is formed.

  Further, according to radio receiving apparatus 200 according to the present embodiment, geometry calculation unit 205 generates a geometry based only on the power measurement value of the received signal, so that power from the own cell and other cells can be obtained with a simple configuration. Power and noise can be separated.

  In addition, according to radio receiving apparatus 200 according to the present embodiment, reception method for the received signal is determined by reception method determination unit 206 based on the geometry calculated by geometry calculation unit 205, and therefore, depending on the propagation environment. Instead, the optimum reception method can be selected, and the reception quality can be improved.

  Also, according to the mobile station apparatus according to the present embodiment, the optimal reception scheme can be selected by radio reception apparatus 200 having a simple configuration regardless of the propagation environment, so that reception quality can be reduced while suppressing power consumption. Can be improved.

  The present embodiment may be modified or applied as follows. In the present embodiment, by using the total received power of the own cell (total sum of own cell interference) and RSCP obtained by the conventional SIR measurement method, the ratio (Ec / Ior). Then, the reception method determination unit 206 may determine the reception method in the demodulation unit 207 based on this Ec / Ior. For example, if Ec / Ior is less than or equal to a predetermined threshold, the interference canceller is turned off and RAKE reception is performed.

  Further, in the present embodiment, the reception method determination unit 206 may determine the reception method in the demodulation unit 207 by comparing the sum of Ec / Ior and geometry with a predetermined threshold value. In this way, an optimal reception method can be selected regardless of the absolute amount of transmission power of the desired signal, and reception quality can be improved.

  Further, in radio receiving apparatus 200 according to the present embodiment, despreading section 204 and demodulating section 207 are provided separately, but these may be combined and configured with one receiving circuit.

(Embodiment 2)
FIG. 3 is a block diagram showing a configuration of radio receiving apparatus 300 according to Embodiment 2 of the present invention. The radio reception apparatus 300 is mounted on the mobile station apparatus similarly to the radio reception apparatus 200, and generates reception quality information for adaptive modulation and transmits it to the base station apparatus. The wireless reception device 300 further includes a quality measurement unit 311, a multipath (MP) interference amount calculation unit 312, and a conversion unit 313 in addition to the components in the wireless reception device 200. Accordingly, since the wireless reception device 300 includes many components that perform the same functions as the components of the wireless reception device 200, the components that perform the same function are the same as those of the wireless reception device 200. The same reference numerals as those of the constituent parts are attached and the description thereof is omitted.

  The quality measurement unit 311 calculates the SIR by RAKE combining the received signal input from the despreading unit 204 by the conventional SIR measurement method, and inputs the calculated SIR to the conversion unit 313.

The MP interference amount calculation unit 312 measures the multipath interference amount in the reception signal input from the despreading unit 204. Specifically, the MP interference amount calculation unit 312 calculates the multipath interference amount by performing the calculation according to the following equation (23) using, for example, “signal power to multipath interference power ratio” as an index of the multipath interference amount. calculate. Then, the MP interference amount calculation unit 312 inputs the calculated multipath interference amount to the conversion unit 313.

  The conversion unit 313 holds a table or a conversion formula that evaluates the difference in reception quality between the case where RAKE combining is performed on the received signal and the case where adaptive reception is performed in association with the propagation environment and the geometry. Then, the conversion unit 313 refers to a table held based on the geometry input from the geometry calculation unit 205 and the multipath interference amount input from the MP interference amount calculation unit 312. Alternatively, by applying these to the stored conversion formula, reception quality information (SIR) in the case of adaptive reception from the SIR input from the quality measurement unit 311 is generated. Then, the conversion unit 313 inputs the generated reception quality information to a baseband unit (not shown) or the like. Thereafter, this reception quality information is transmitted to the base station apparatus and used for adaptive modulation.

FIG. 4 shows an example of a table held in the conversion unit 313. An example of a conversion formula held in the conversion unit 313 is shown below. In this conversion formula, α and β are predetermined constants.
SIR = RAKE reception SIR + β (multipath interference amount × α · Geometry)

  Therefore, according to the present embodiment, reception quality after RAKE combining is converted into reception quality after adaptive reception by an adaptive equalizer or the like according to the propagation environment by conversion section 313. It is not necessary to separately operate an adaptive equalizer or the like for reporting, power consumption in the mobile station apparatus can be suppressed, and high-accuracy reception quality information can be reported to the base station apparatus.

  The present embodiment may be modified or applied as follows. In other words, when Expression (23) is used, the SIR becomes infinite when the propagation environment is improved to be one path. Therefore, the conversion unit 313 may generate the reciprocal number of Expression (23) as reception quality information.

  Further, in radio reception apparatus 300 according to the present embodiment, reception method determination unit 206 in radio reception apparatus 200 is not clearly shown, but reception method determination unit 206 may be provided.

  Further, the quality measuring unit 311 may obtain the power of each path from the delay profile of the received signal in order to reduce the signal processing load.

  Further, the table held in the quality measuring unit 311 may indicate an improvement amount from the SIR by the RAKE reception, or may indicate an absolute value of the converted SIR.

  The geometry measuring method, the radio receiving apparatus and the mobile station apparatus according to the present invention can separate the power from the own cell and the power and noise from other cells with a simple configuration, and can move regardless of the propagation environment. It has the effect of improving the reception quality while suppressing the power consumption of the station apparatus, and is useful as a mobile phone or the like used in a cellular radio communication system.

The figure which shows an example of the delay profile of the received signal which concerns on Embodiment 1 of this invention. FIG. 2 is a block diagram showing a configuration of a radio reception apparatus according to Embodiment 1 of the present invention. The block diagram which shows the structure of the radio | wireless receiver which concerns on Embodiment 2 of this invention. The figure which shows an example of the table hold | maintained at the conversion part in Embodiment 2 of this invention.

Explanation of symbols

200, 300 Radio reception apparatus 201 Antenna 202 Radio reception unit 203 Path search unit 204 Despreading unit 205 Geometry calculation unit 206 Reception method determination unit 207 Demodulation unit 208 Decoding unit 311 Quality measurement unit 312 Multipath (MP) interference amount calculation unit 313 Conversion unit

Claims (6)

A geometry measurement method used by a radio receiver in a cellular radio communication system, comprising:
An interference signal power measurement step for measuring the power of the interference signal included in the received signal for each path;
A summing step of summing the measured interference signal power for each path for N paths;
A non-path interference signal power level measuring step for measuring power of an interference signal other than a path included in the received signal; and
A self-cell interference signal power calculating step of calculating the self-cell interference signal power by subtracting the summed result in the summing step from a value obtained by multiplying the measured interference signal power other than the path by N;
Other cell interference signal / noise power calculation step of calculating a sum of power of other cell interference signal and noise by subtracting the own cell interference signal power calculated from the measured interference signal power other than the path,
A geometry calculating step of calculating a geometry by dividing the calculated own cell interference signal power by the calculated power of the other cell interference signal and noise;
The geometry measuring method characterized by comprising. A wireless receiver in a cellular wireless communication system,
Measure the power of the interference signal included in the received signal for each path, add the measured interference signal power for each path for N paths, measure the power of the interference signal other than the path included in the received signal, The self-cell interference signal power is calculated by subtracting the sum of the interference signal power for each path from the value obtained by multiplying the interference signal power for each path by N times from the value obtained by multiplying the interference signal power for other paths by N, and the self-cell interference signal power is calculated from the interference signal power for other paths. A sum of powers of other cell interference signals and noise is calculated by subtracting the cell interference signal power, and the self-cell interference signal power is divided by a sum of powers of the other cell interference signals and noise. Geometry calculation means for calculating
A wireless receiver characterized by comprising: A receiving method determining unit that determines a receiving method for the received signal based on the geometry calculated by the geometry calculating unit;
Received signal processing means for processing the received signal in the receiving method determined by the receiving method determining means;
The wireless receiver according to claim 2, further comprising: Further comprising estimation means for estimating the ratio of desired signal power to the total transmission power of the base station,
The reception method determination unit determines a reception method for the reception signal based on an estimation result by the estimation unit and a geometry calculated by the geometry calculation unit.
The wireless receiver according to claim 3. Reception quality measuring means for measuring the reception quality of the received signal;
Interference amount calculating means for calculating the amount of multipath interference in the received signal;
Conversion means for converting the measured reception quality into reception quality after adaptive reception according to the geometry calculated by the geometry calculation means and the calculated multipath interference amount;
The wireless receiver according to claim 2, further comprising:   A mobile station apparatus comprising the radio reception apparatus according to claim 3.

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