CN1983839A

CN1983839A - Method, device and PAKE receiver of each radial weighted value of computer

Info

Publication number: CN1983839A
Application number: CNA2006100785426A
Authority: CN
Inventors: 许海红; 赵治林; 余志坚
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2006-05-10
Filing date: 2006-05-10
Publication date: 2007-06-20
Anticipated expiration: 2026-05-10
Also published as: WO2007128184A1; CN100578954C

Abstract

The invention discloses a method for calculating the weighted value of each path. The method is used in a RAKE receiver or a general RAKE (G-RAKE) receiver, and the multiple access interference function R _MUI obtained through calculation and the interference of background thermal noise function R _n to obtain the noise correlation matrix R _u ; according to the obtained fading function h of each path and the noise correlation matrix R _u , the weighted value ω of each path is calculated. The invention also discloses a device for calculating the weighted value of each path according to the above method, and a RAKE receiver for calculating the weighted value of each path by using the above method. By applying the scheme of the invention, the calculation amount for calculating the combination weight of each path can be effectively reduced under the premise that the performance of the G-RAKE receiver is hardly affected. Moreover, the calculation of the weight value of each path has nothing to do with the spreading factor, and users with different spreading factors can share one RAKE receiver without additionally increasing the number of RAKE receivers for users with different spreading factors.

Description

Method and device for calculating weighted value of each path and RAKE receiver

Technical Field

The present invention relates to wireless communication signal receiving technology, and in particular, to a method and an apparatus for calculating weighted values of each path, and a RAKE receiver.

Background

In Code Division Multiplexed (CDMA) spread spectrum systems, the channel bandwidth is much larger than the flat fading bandwidth of the channel. Unlike conventional modulation techniques that require an equalization algorithm to cancel intersymbol interference between adjacent symbols, CDMA spreading codes require good autocorrelation properties in selecting the signal. Thus, the delay spread occurring in the radio channel can be regarded as simply a retransmission of the transmitted signal. Multipath signals may be considered to be uncorrelated if they are delayed relative to each other by more than one chip period.

Since the multipath signals contain available information, the receiver can improve the signal-to-noise ratio of the received signals by combining the multipath signals, and the receiver adopting such signal processing is called a RAKE receiver. Fig. 1 is a schematic structural diagram of a RAKE receiver, which specifically includes the following modules:

a multipath searching and distributing module 110, configured to receive a signal, complete multipath delay capturing and multipath delay distributing on the received signal, and output the processed delay information of each multipath to the descrambling and despreading module 120, the channel estimation module 130, and the weighted value calculation module 140;

a descrambling and despreading module 120, configured to complete descrambling and despreading operations on the chip-level received signal according to the input multipath delay information and scrambling code and spreading code information in the received signal, and output a descrambled and despread symbol-level received signal y to each path merging module 150;

the channel estimation module 130 estimates the channel fading condition of each time delay according to the input multipath time delay information, and outputs the channel fading information corresponding to each multipath time delay to the weighted value calculation module 140 of each path;

the weighted value calculating module 140 of each path calculates the system Gaussian noise power N according to the input multipath delay information, the channel fading information of each path and other external parameters₀And receiving the chip level energy E of the user_iCalculating a weighting factor ω of each path, and outputting the calculated weighting factor ω to each path merging module 150;

the path merging module 150 uses the formula Y ═ ω for the descrambled and despread path data Y according to the input path weighting factor ω^HThe xy is combined, and the signal Y obtained after the combination is output to the demodulation decoding module 160; wherein]^HRepresenting a conjugate transpose;

the demodulation decoding module 160 performs corresponding demodulation and decoding operations on the received signal Y, and outputs a signal after demodulation decoding.

In order to meet the increasing rate requirements of users, various technologies with higher and higher peak rates, such as High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA), are introduced into the existing wireless communication system. The introduction of these new techniques presents significant challenges to conventional RAKE reception techniques. On one hand, the traditional RAKE receiver technology cannot meet the throughput requirement of high-speed service; on the other hand, due to the self-interference characteristic of the CDMA system, it is required that the interference generated by the high-rate service user to other users should be as small as possible, that is, the required signal-to-noise ratio (SNR) of the high-rate service user is reduced as much as possible on the premise of meeting the performance index of the high-rate service. Therefore, it is highly desirable to introduce advanced reception techniques with performance superior to conventional RAKE receivers.

Receivers with superior performance over conventional RAKE receivers include the following:

the enhanced RAKE receiver is improved on the basis of the traditional RAKE receiving technology, and the performance improvement is very limited;

the receiver can theoretically completely eliminate intersymbol interference (ISI) caused by multipath and multiple access interference (MUI) between different users so as to obtain good performance, but has great impact on the existing receiver structure due to great difference between the structure of the receiver and the traditional RAKE receiver;

the general RAKE (G-RAKE) receiver fundamentally considers the dominant factors limiting the performance of the traditional RAKE receiver, not only can achieve the same performance as the equalization receiver, but also has a similar implementation structure as the traditional RAKE receiver.

The structure of the G-RAKE receiver is similar to that of the conventional RAKE receiver shown in fig. 1, except that the specific calculation process of each of the path weight value calculation blocks 140 is different from that of the conventional RAKE receiver.

The calculation of each path weight value of the G-RAKE receiver requires calculation

Wherein,

h is the quantity related to each path fading information, a unified Chinese name is not available in the field at present, and h is called each path fading function for convenience of description;

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+ N_{0} R_{p} (d_{1} - d_{2}) .

in the formula (2) or (3), E₀Symbol level energy for the target user, E_ISymbol level energy, N, for interfering users₀The single-sided power spectral density of the system white gaussian noise, the symbol-level energy and the single-sided power spectral density of the system white gaussian noise can be estimated according to a related algorithm, and in a receiver system, the quantities are used as known parameters; n is the spreading factor of the target user, R_ISIAs a function of intersymbol interference, R_MUIAs a function of multiple access interference, T_cFor the duration of one spreading chip, T ═ NT_c，g_l、g_qChannel fading factors, τ, for the l-th and q-th paths, respectively_l、τ_qIs the multipath propagation delay of the L-th path and the q-th path, L is the total number of effective paths, R_pObtaining an autocorrelation function of a transmit pulse shaping filter in advance according to a computational expression of a shaping filter used by a system; d. d₁And d₂To solve the multipath delay corresponding to the diameter expansion.

According to the above calculation method, the calculation of each path weight value of the G-RAKE receiver as shown in fig. 2 includes the following steps:

step 201: according to the input path fading factor g_lMultipath position τ_lAnd symbol level energy E of target user₀H is calculated by using the formula (2);

step 202: finding R_ISI: as can be seen from equation (3):

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the step is based on the input fading factors g of each path_lMultipath position tau_lMultipath time delays d, d corresponding to the solution of the hole enlargement₁And d₂Andequation (4) calculates the intersymbol interference function R_ISI；

Step 203: finding R_MUI: as can be seen from equation (3):

the step is based on the input fading factors g of each path_lMultipath position tau_lMultipath time delay d, d corresponding to diameter expanding₁And d₂And equation (4) calculating a multiple access interference function R_MUI；

Step 204: finding R_n′: as can be seen from equation (3):

R_n′＝R_p(d₁-d₂) (6)

this step is based on the autocorrelation function R of the shaping filter_pInput multipath time delay d₁And d₂Calculating the interference function R of the background thermal noise by using the formula (6)_n′；

Step 205: according to the input spreading factor N of the target user and the symbol level energy E of the target user₀Symbol level energy E of interfering users_ISingle-sided power spectral density N of system Gaussian white noise₀And the calculation results of step 202 to step 204, calculating to obtain a noise correlation matrix R_u；

Step 206: according to the noise correlation matrix R obtained in step 205_uAnd h obtained in step 201, to obtain the path combining weighting factors of the G-RAKE receiver.

However, compared with the conventional RAKE receiver, the processing method for calculating the weighted values of each path adopted by the G-RAKE receiver requires a large amount of calculation overhead, and thus the implementation complexity and cost are high.

Disclosure of Invention

In view of the above, the present invention provides a method for calculating a weighted value of each path, which can effectively reduce the computation of the combining weighted value of each path. The method comprises the following steps:

A. calculating each path fading function h according to the input each path fading factor, the multipath position information and the symbol level energy of the target user;

B. according to the input fading factors of all paths, the multi-path position information and the multi-path time delay corresponding to the de-expanding, the multi-address interference function R is calculated_MUI；

C. According to the autocorrelation function R of the shaping filter_pInput multipath time delay, and calculating the interference function R of the background thermal noise_n′；

D. Based on the sum E of the inputted chip-level energies of all users independent of the spreading factor_{c_T}Single-sided power spectral density N of system Gaussian white noise₀And the calculation results of the step B and the step C are calculated to obtain a noise correlation matrix R_u；

E. According to the fading functions h of all paths obtained in the step A and the noise correlation matrix R obtained in the step D_uAnd calculating to obtain the weighted value omega of each diameter.

Step A, calculating each path fading function h as:

according to the formula

Calculating each path fading function h, wherein E₀Symbol level energy, g, for the target user_lIs the channel fading factor, R, of the l path_pIs the autocorrelation function of the transmit pulse shaping filter, d is the multipath time delay corresponding to the de-expansion, τ_lIs the multipath propagation delay of the l-th path.

Step B calculating multiple access interference function R_MUIComprises the following steps:

according to the formula

Calculating a multiple access interference function R_MUI(ii) a Where N is the spreading factor of the target user, l and q are the labels of the paths, g_lAnd g_qFor each path fading factor, τ_lAnd τ_qIs the multipath location information, L is the total number of effective paths, d₁And d₂To solve the multipath delay corresponding to the diameter expansion.

C, calculating the interference function R of the background thermal noise_n′Comprises the following steps: according to the formula R_n′＝R_p(d₁-d₂) Calculating the interference function R of the background thermal noise_n′Wherein R is_pFor the autocorrelation function of the transmit pulse shaping filter, d₁And d₂To solve the multipath delay corresponding to the diameter expansion.

Step D calculating the noise correlation matrix R_uComprises the following steps:

according to the formula

Computing a noise correlation matrix R_u(ii) a Where N is the spreading factor of the target user, l and q are the labels of the paths, g_lAnd g_qFor each path fading factor, τ_lAnd τ_qIs the multipath location information, L is the total number of effective paths, d₁And d₂To solve the multipath delay corresponding to the expansion, E_{c_T}Is the sum of all user chip-level energies, R (n), independent of the spreading factor₁，n₂) Is n₁And n₂Of (2), wherein

N_OVSIs the sampling rate.

And E, calculating to obtain the weighted value omega of each diameter as follows: according to the formula

The weighted value ω of each path is obtained.

Another objective of the present invention is to provide an apparatus for calculating weighted values of each path in a RAKE receiver system, which specifically includes:

each path fading function calculating unit is used for receiving the target user symbol level energy from a descrambling and despreading module of the RAKE receiver, calculating each path fading function h by the multipath fading factor and the multipath position information of the channel estimation module, and inputting each path fading function h obtained by calculation into the weighted value synthesizing unit;

a multiple access interference function calculation unit for receiving multipath fading factor and multipath position information from the channel estimation module of the RAKE receiverAnd calculating a multiple access interference function R from the multipath search assignment module multipath time delays_MUIAnd calculating the multiple access interference function R_MUIAn input noise correlation matrix calculation unit;

a thermal noise interference function calculation unit for receiving multipath time delay of multipath search distribution module of RAKE receiver, and autocorrelation function of shaping filter, calculating interference function R of background thermal noise_n′And calculating the interference function R of the background thermal noise_n′An input noise correlation matrix calculation unit;

a noise correlation matrix calculation unit for calculating a multiple access interference function R from the multiple access interference function_MUIInterference function R of background thermal noise of thermal noise interference function calculation unit_n′Sum of all user chip-level energies of the receiver system E_{c_T}And single-sided power spectral density N of system Gaussian white noise₀And calculating to obtain a noise correlation matrix R_uAnd correlating the resulting noise correlation matrix R_uAn input weight value synthesizing unit;

a weight value synthesis unit for synthesizing the weighted values according to the received path fading functions h and the noise correlation matrix R_uThe weighted values ω of the respective paths are synthesized and the synthesized weighted values ω of the respective paths are output to the respective path merging modules.

The noise correlation matrix calculation unit calculates to obtain a noise correlation matrix R_uThe method comprises the following steps: let the intersymbol interference function be a multiple access interference function R_ISIEqual to the multiple access interference function R_MUIAnd according to an intersymbol interference function R_ISIMultiple access interference function R_MUIBackground thermal noise interference function R_n′Sum of all user chip-level energies of the receiver system E_{c_T}And single-sided power spectral density N of system Gaussian white noise₀And calculating to obtain a noise correlation matrix R_u。

The RAKE receiver is a generalized RAKE receiver.

Another objective of the present invention is to provide a RAKE receiver for calculating each path weight value by using the above method, which includes a multipath searching and distributing module, a descrambling and despreading module, a channel estimation module, a path weight value calculating module, a path combining module and a demodulation and decoding module, wherein the path weight value calculating module includes:

each path fading function calculating unit is used for receiving the target user symbol level energy from the descrambling and despreading module, the multipath fading factor and the multipath position information of the channel estimation module, calculating each path fading function h, and inputting each path fading function h obtained by calculation into the weighted value synthesizing unit;

a multiple access interference function calculation unit for receiving the multipath fading factor and multipath position information from the channel estimation module, and the multipath time delay from the multipath search distribution module and calculating the multiple access interference function R_MUIAnd calculating the multiple access interference function R_MUIAn input noise correlation matrix calculation unit;

a thermal noise interference function calculation unit for receiving the multipath time delay of the multipath search distribution module, and the autocorrelation function of the shaping filter, and calculating the interference function R of the bottom thermal noise_n′And calculating the interference function R of the background thermal noise_n′An input noise correlation matrix calculation unit;

a weight value synthesis unit for synthesizing the weighted values according to the received path fading functions h and the noise correlation matrix R_uSynthesizing the weighted value omega of each path and outputting to the merging modules of each pathThe combined radial weights ω.

The RAKE receiver is a generalized RAKE receiver.

It can be seen from the above technical solutions that, in the process of calculating the weighted value of each path, the method of the present invention does not need to calculate the inter-symbol interference function, so that compared with the G-RAKE receiver, the method of the present invention can effectively reduce the computation of the combining weights of each path, and the quality of the output signal is hardly affected; moreover, the calculation of each radial weighting value is independent of the spreading factor, and users with different spreading factors can share one RAKE receiver without increasing the number of RAKE receivers for users with different spreading factors. By adopting the scheme of the invention, the calculation overhead and the realization complexity can be greatly reduced and the cost can be saved on the premise of outputting the signals with the same quality as the G-RAKE receiver.

Drawings

FIG. 1 is a schematic diagram of a RAKE receiver or G-RAKE receiver architecture;

FIG. 2 is a flow diagram of a prior art implementation of the path weight calculation modules of a G-RAKE receiver;

FIG. 3 is a flow chart of the implementation of the path weight calculation modules of the RAKE receiver according to the present invention;

fig. 4 is a block diagram of the calculation module of each radial weight value of the RAKE receiver according to the embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings.

According to the simplified formula (7) proposed by the prior art for the calculation method of the respective path weight values of the G-RAKE receiver:

= R (n_{1}, n_{2}),

equation (3) can be reduced to:

+ N_{0} R_{p} (d_{1} - d_{2}),

wherein R (n)₁，n₂) Is n₁And n₂The correlation function of (a) is determined,

N_OVSis the sampling rate of the G-RAKE receiver module.

From equation (3) one can see the matrix R_uIn the constituent elements of (1), R_ISIAnd R_MUIThe expression of (c) differs only in the summation of i: the former reduces the summation operation when i is 0 than the latter. Is due to R_ISIAnd R_MUIThis difference in (c) results in a simplified pair R in equation (8)_ISIThe calculation of (2) involves a summation operation of the products of the 2N-1 terms. If R is considered in the implementation of G-RAKE_ISI＝R_MUIThen equation (8) can be further simplified to:

+ N_{0} R_{p} (d_{1} - d_{2})

wherein E_T＝E₀+E_IAnd is the symbol level energy. Table 1 shows the computation amount of each time slot of the G-RAKE receiver, where M is the number of iterations for obtaining the weighted value ω, and is generally 1-3; j is the total number of fingers of the G-RAKE receiver,the value is generally J ≈ 2L.

TABLE 1

As can be seen from the data in Table 1, R is determined_ISIAnd R_MUIOccupies a considerable weight in the total computation of G-RAKE, and therefore R is considered in the G-RAKE implementation process_ISI＝R_MUIThe operation amount of the G-RAKE receiver is effectively reduced, and the implementation complexity is reduced.

According to the formula (8), since R_ISI＝R_MUICalculating R_uTime and energy E₀、E_IThe matrices multiplied are equal, so that only the total symbol level energy E needs to be known_TWithout distinguishing E therefrom₀、E_IFurther, the number of parameters required by the G-RAKE receiver can be reduced, and the implementation complexity of the G-RAKE receiver is further reduced.

Further, as can be seen from the formulas (4) and (5), R_MUISpreading factor ofCan be extracted, so equation (8) can be rewritten as:

namely R_MUIFrom E energy weighting factor_TBecome into

\frac{E_{T}}{N} = E_{c_T},

I.e., the sum of all user chip-level energies independent of the spreading factor, so R_uIs independent of the spreading factor. Therefore if R is considered in the G-RAKE implementation_ISI＝R_MUIAll users can share the calculation result of one G-RAKE receiver as long as the transmission environment of the users carrying out G-RAKE reception is the same, namely multipath delay and channel fading are the same.

Based on the above analysis, the G-RAKE receiver according to the embodiment of the present invention adopts the structure shown in fig. 1, that is, the structure of the existing G-RAKE receiver or the existing RAKE receiver, except that the implementation process of each radial weight value calculation module in the G-RAKE receiver or the existing RAKE receiver adopts the scheme of the present invention, as specifically shown in fig. 3, the G-RAKE receiver includes the following steps:

step 301: according to the input path fading factor g_lMultipath position τ_lAnd symbol level energy E of target user₀Calculating each path fading function h by using a formula (2); the step is the same as step 201 in the implementation process of the weight calculation module of the existing G-RAKE receiver;

step 302: finding R_MUI: from the formula (12), it can be seen that

The step is based on the input fading factors g of each path_lMultipath position tau_lMultipath time delay d, d corresponding to diameter expanding₁And d₂And equation (13) calculating a multiple access interference function R_MUI；

Step 303: finding R_n′: from the formula (12), it can be seen that

R_n′＝R_p(d₁-d₂) (14)

This step is based on the autocorrelation function R of the shaping filter_pInput multipath time delay d₁And d₂Calculating an interference function R of the background thermal noise according to the formula (14)_n′(ii) a Equation (14) is the same as equation (6), so this step is the same as step 204 in the implementation process of the weight calculation module of the existing G-RAKE receiver;

step 304: based on the sum E of the inputted chip-level energies of all users independent of the spreading factor_{c_T}Single-sided power spectral density N of system Gaussian white noise₀And the calculation results of the step 302 and the step 303 are calculated according to the formula (12) to obtain the noise correlation matrix R_u；

Step 305: according to the path fading functions h obtained in step 301 and the noise correlation matrix R obtained in step 304_uThe weighted value ω of each path of the G-RAKE receiver is calculated by equation (1).

To implement the above method, the structure and connection relationship of each part of the weighted value calculation module 140 of the RAKE receiver according to the embodiment of the present invention is shown in fig. 4, which specifically includes the following steps:

each path fading function calculating unit 141 for receiving the target user symbol level energy E from the descrambling and despreading module 120₀And a multipath fading factor g of the channel estimation module 130_lAnd multipath position information tau_lCalculating each path fading function h according to formula (2) using the received parameters, and inputting each calculated path fading function h to the weighted value synthesizing unit 145;

a multiple access interference function calculation unit 142 for receiving the multipath fading factor g from the channel estimation module 130_lAnd multipath position information tau_lAnd multipath delays d, d of the multipath search assignment module 110₁And d₂Calculating a multiple access interference function R according to equation (13) using the received parameters_MUIAnd calculating the multiple access interference function R_MUIAn input noise correlation matrix calculation unit 144;

a thermal noise interference function calculating unit 143 for receiving the multipath time delay d of the multipath search allocating module 110₁And d₂And the autocorrelation function R of the shaping filter_pCalculating the interference function R of the noise floor according to equation (14) using the received parameters_n′And calculating the interference function R of the background thermal noise_n′An input noise correlation matrix calculation unit 144;

a noise correlation matrix calculation unit 144 for calculating a multiple access interference function R according to the multiple access interference function from the multiple access interference function calculation unit 142_MUIInterference function R of background thermal noise of thermal noise interference function calculation unit 143_n′Sum of all user chip-level energies of the receiver system E_{c_T}And single-sided power spectral density N of system Gaussian white noise₀Calculating to obtain a noise correlation matrix R according to the formula (12)_uAnd correlating the resulting noise correlation matrix R_uAn input weight value synthesizing unit 145;

a weighted value synthesizing unit 145 for synthesizing the weighted values according to the received path fading functions h and the noise correlation matrix R_uThe weighted values ω are synthesized by the formula (1), and the synthesized weighted values ω are output to the path merging modules 150.

Figure 4 shows an embodiment of the invention in which the path weight value calculation blocks have a reduced number of intersymbol interference function calculation units and associated input-output connections compared to prior art G-RAKE receiver path weight value calculation blocks; in the processing method, the expense for calculating the intersymbol interference function is correspondingly saved.

The path weight value calculation module shown in fig. 4 is used as the path weight value calculation module 140 of the RAKE receiver shown in fig. 1, and the connection relationship between the structure and each part of the RAKE receiver shown in fig. 1 is the connection relationship between the structure and each part of the RAKE receiver of the present invention.

Simulation analysis of the G-RAKE receiver proposed by the scheme of the invention shows that R is considered in the implementation process of the G-RAKE receiver_ISI＝R_MUIHardly affecting the output result of the G-RAKE receiver. Therefore, R is considered in the implementation of the G-RAKE receiver_ISI＝R_MUIOn the premise of not influencing the quality of output signals, the operation amount of the G-RAKE receiver can be effectively reduced, the number of parameters required by the G-RAKE receiver is reduced, and the implementation complexity of the G-RAKE receiver is further reduced; and makes the calculation of the G-RAKE weighted value independent of the spreading factor, users with different spreading factors can share one G-RAKE receiver without adding the number of G-RAKE receivers for users with different spreading factors.

Those skilled in the art should recognize that, since the structural difference between the G-RAKE receiver and the RAKE receiver is mainly due to the difference between the respective radial weight value calculation modules, the method for calculating the respective radial weight values and the apparatus for implementing the calculation method proposed by the present invention can be applied not only to the G-RAKE receiver but also to the RAKE receiver having the same or similar structure.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A method of calculating a weighted value for each path, the method comprising the steps of:

C. According to the autocorrelation function R of the shaping filter_pInput multipath time delay, calculation bookInterference function R of bottom thermal noise_n′；

2. The method of claim 1, wherein the step a of calculating each radial fading function h is:

according to the formula

3. Method according to claim 1, characterized in that said calculation of the multiple access interference function R of step B is carried out_MUIComprises the following steps:

according to the formula

Calculating a multiple access interference function R_MUI(ii) a Where N is the spreading factor of the target user, l and q are the labels of the paths, g_lAnd g_qFor each path fading factor, τ_lAnd τ_qIs the multipath location information, L is the total number of effective paths, d₁And d₂To solve g_qAnd multipath time delay corresponding to the path.

4. The method according to claim 1, wherein the step C of calculating the interference function R of the background thermal noise_n′Comprises the following steps: according to the formula R_n′＝R_p(d₁-d₂) Calculating the interference function R of the background thermal noise_n′Wherein R is_pFor the autocorrelation function of the transmit pulse shaping filter, d₁And d₂To solve the multipath delay corresponding to the diameter expansion.

5. The method of claim 1, wherein step D comprises computing a noise correlation matrix R_uComprises the following steps:

according to the formula

，N_OVSIs the sampling rate.

6. The method according to any one of claims 1 to 5, wherein the calculation of step E yields a respective radial weighting value ω of: according to the formula

The weighted value ω of each path is obtained.

7. An apparatus for calculating weight values for paths in a RAKE receiver system, the apparatus comprising:

each path fading function calculating unit, which is used to receive the target user symbol level energy from the descrambling and despreading module of the RAKE receiver, the multipath fading factor and the multipath position information of the channel estimation module, calculate each path fading function h, and input the calculated each path fading function h into the weighted value synthesizing unit;

a multiple access interference function calculation unit for receiving the multipath fading factor and multipath position information from the channel estimation module of the RAKE receiver, and the multipath time delay from the multipath search distribution module and calculating the multiple access interference function R_MUIAnd calculating the multiple access interference function R_MUIAn input noise correlation matrix calculation unit;

8. The apparatus according to claim 7, wherein the noise correlation matrix calculation unit calculates a noise correlation matrix R_uThe method comprises the following steps: let the intersymbol interference function be a multiple access interference function R_ISIEqual to the multiple access interference function R_MUIAnd according to an intersymbol interference function R_ISIMultiple access interference function R_MUIBackground thermal noise interference function R_n′Sum of all user chip-level energies of the receiver system E_{c_T}And single-sided power spectral density N of system Gaussian white noise₀And calculating to obtain a noise correlation matrix R_u。

9. The apparatus of claim 7 or 8, wherein the RAKE receiver is a generalized RAKE receiver.

10. A RAKE receiver for calculating weighted value of each path includes multipath searching distribution module, descrambling and despreading module, channel estimation module, weighted value calculation module of each path, combining module of each path and demodulation decoding module, the weighted value calculation module of each path includes:

each path fading function calculating unit is used for receiving the target user symbol level energy from the descrambling and despreading module, calculating each path fading function h by the multipath fading factor and the multipath position information of the channel estimation module, and inputting each path fading function h obtained by calculation into the weighted value synthesizing unit;

11. The RAKE receiver of claim 10,the noise correlation matrix calculation unit calculates to obtain a noise correlation matrix R_uThe method comprises the following steps: let the intersymbol interference function be a multiple access interference function R_ISIEqual to the multiple access interference function R_MUIAnd according to an intersymbol interference function R_ISIMultiple access interference function R_MUIBackground thermal noise interference function R_n′Sum of all user chip-level energies of the receiver system E_{c_T}And single-sided power spectral density N of system Gaussian white noise₀And calculating to obtain a noise correlation matrix R_u。

12. The RAKE receiver of claim 10 or 11, wherein the RAKE receiver is a generalized RAKE receiver.