WO2011088685A1

WO2011088685A1 - Method and apparatus for bit-interception of baseband signal

Info

Publication number: WO2011088685A1
Application number: PCT/CN2010/077063
Authority: WO
Inventors: 赵天虹; 官华伯; 闫晓伟
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-01-20
Filing date: 2010-09-17
Publication date: 2011-07-28
Also published as: CN102130863B; CN102130863A

Abstract

The present invention discloses a method and an apparatus for bit-interception of baseband signals. The method includes that: signal processing is performed to the baseband signals and an amplitude delay profile (ADP) set is obtained; the maximum of energy paths is adopted as a bit-interception parameter, wherein the maximum is obtained by utilizing last threshold detection, and total 8-12 bits, which include the bit where the maximum of energy paths of the ADP set is located and the download bits thereof, are intercepted as sampling data; or, a noise mean which is obtained by utilizing last threshold detection is adopted as the bit-interception parameter, and total 8-12 bits, which include the bit where the noise mean of the ADP set is located and the upload bits thereof, are intercepted as the sampling data. The present invention can reduce the bit width of the signals, and the effect that the chip memory space and power consumption are reduced can be achieved, and the chip cost is saved. If one of the sampling data is intercepted to 8 bits, the memory space is half of the original memory space wherein 12-16 bits are stored into two 8-bit-RAMs.

Description

Method and device for intercepting baseband signal

The present invention relates to a wideband code division multiple access communication system, and more particularly to a method and apparatus for intercepting a baseband signal.

Background technique

In the Wide Code Division Multiple Access (WCDMA) communication system, the base station needs to perform search synchronization on the uplink signal, and the terminal needs to perform search synchronization on the downlink signal, and the radio frequency module of the base station and the terminal receives the radio frequency signal, and the signal is received. Demodulation is performed to obtain baseband information. The baseband processor performs descrambling and despreading on the baseband signal, and the data after descrambling and despreading is subjected to coherent accumulation and non-coherent accumulation, and the amplitude obtained by coherent accumulation and non-coherent accumulation is obtained. The Amplitude Delay Profile (ADP) collection is truncated.

The current interception method is a fixed intercept method that cuts off the saturated portion of the high energy coherence and the noise portion of the low energy coherence. A series of operations such as filtering, threshold detection, and path selection after truncation.

The base station needs to store data of multiple radio links of each terminal, and the fixed truncation method uniformly processes the data, and the method is simple, but for different channels, the data interception obtained by the fixed truncation method has more redundant information. The base station generally searches for hundreds of terminal signals, and the RAM (random memory) space is relatively large, and the cost and power consumption of the baseband processor is a huge consumption.

Summary of the invention

The invention provides a method and a device for intercepting a baseband signal, which solves the problem of more data redundancy information obtained by the interception of the fixed intercept method, and realizes more effective interception of data to reduce the cost and work of the storage space and the baseband processor. Cost of consumption.

A method for intercepting a baseband signal according to the present invention includes:

Signal processing the baseband signal to obtain an amplitude delay profile (ADP) set; The maximum value of the energy path obtained by the previous threshold detection is used as the intercept parameter, and the maximum value of the energy path of the ADP set and the total 8~12 bits of the ADP set are taken as sampling data; or the previous gate P艮 detection is used. The noise mean value is used as the intercept parameter, and a total of 8~12 bits of the noise mean value of the ADP set and above are taken as sampling data.

The method may further include: after completing the truncation with the maximum value of the energy path or the mean value of the noise, and performing the truncation again, according to the maximum value of the energy path or the noise mean obtained by the last threshold detection, according to the previous intercepted sampling The highest and lowest bits of the data, the translation interception range, so that the previous bit of the highest bit of the obtained sampled data is a saturated bit, or the last bit of the lowest bit is a noise bit. The step of shifting the interception range may include: if the maximum value of the energy path obtained by the last threshold detection is between 192 and 256, the interception range is shifted to the left by one bit; if between 96 and 192, the interception range is unchanged; If it is between 48~%, it will shift to the right by one bit; if it is between 24~48, it will shift to the right by two digits; if it is between 12~24, it will shift to the right by three digits; if it is between 6~12 Between the two, the four bits are shifted to the right; if between 3 and 6, the five bits are shifted to the right; if between 1 and 3, the six bits are shifted to the right; if between 0 and 1, the Shift the right seven digits.

The step of translating the interception range may include: if the average value of the noise obtained by the last threshold detection is between 19 and 26, the interception range is shifted to the left by one bit; if between 10 and 19, the interception range is unchanged; if in the 5~ Between 10, shift one bit to the right; if it is between 2 and 5, shift to the right by two digits; if it is between 0 and 2, shift to three digits to the right.

The method may further include: when the initial truncation is performed, the 12^16 bits of the ADP set are intercepted by the fixed truncation method as sampling data, and the threshold value is used to obtain the maximum value of the energy path and the noise mean value.

The present invention also provides a clipping device for a baseband signal, comprising: a radio frequency module and a baseband processor, the baseband processor including a searcher, wherein:

The radio frequency module is configured to receive the radio frequency signal, demodulate the received radio frequency signal into a baseband signal, and send the signal to the searcher;

The searcher is set to: signal processing the received baseband signal to obtain an amplitude delay profile

(ADP) set; and, using the maximum value of the energy path obtained by the last threshold detection as the intercept parameter, intercepting the maximum value of the energy path of the ADP set and the following 8~12 bits as the sampling data; The average value of the noise obtained from the last threshold detection is used as the intercept parameter, and a total of 8 to 12 bits of the noise mean value of the ADP set and above are taken as the sample data. The searcher can also be set to: when the truncation is performed again by using the maximum value of the energy path or the mean value of the noise, the maximum value of the energy path or the mean value of the noise obtained according to the last threshold detection, according to the previous interception The highest and lowest bits of the sampled data are shifted by the interception range so that the previous bit of the highest bit of the obtained sampled data is a saturated bit, or the last bit of the lowest bit is a noise bit. The searcher can be set to translate the interception range as follows: If the maximum value of the energy path obtained by the last threshold detection is between 192 and 256, shift to the left by one bit; if between 96 and 192, the interception range is not If it is between 48 and 96, it will shift to the right by one bit; if it is between 24 and 48, it will shift to the right by two digits; if it is between 12 and 24, it will shift to the right by three digits; Between ~12, shift to four positions to the right; if between 3 and 6, shift to five digits to the right; if between 1 and 3, shift to six digits to the right; if between 0 and 1, Then pan seven positions to the right.

The searcher can be set to translate the interception range as follows: If the average value of the noise obtained by the last threshold detection is between 19 and 26, the interception range is shifted to the left by one bit; if between 10 and 19, the interception range is unchanged; If it is between 5 and 10, it will shift to the right by one bit; if it is between 2 and 5, it will shift to the right by two digits; if it is between 0 and 2, it will shift to the right by three digits.

The searcher can also be set to: At the initial truncation, intercept the ADP set with a fixed truncation

12-16 bits are used as sampling data, and threshold detection is performed to obtain the maximum value of the energy path and the noise mean.

In summary, the present invention uses the maximum value of the energy path obtained by the last threshold detection or the mean value of the noise to perform the truncation, thereby reducing the bit width of the signal, thereby reducing the chip storage space and power consumption, and saving the cost of the chip. If a sampled data is intercepted by 8 bits (bits), the storage of two 8-bit RAMs by the original 12~16 bits saves 1 times of storage space, and the bit error rate of the method of the present invention can reach 3GPP (3rd Generation Partnership Project) The performance of the product meets the functionality of the product.

Drawing fan

1 is a flow chart of a method for intercepting a baseband signal according to the present invention;

2 is a structural diagram of a clipping device for a baseband signal according to the present invention.

Preferred embodiment of the invention

The embodiment of the present invention adopts the maximum value of the energy path or the noise obtained in the last threshold detection. Value, dynamically truncating the high and low bits to the ADP set. For example, the ADP set uses the maximum value of the last energy path, preferably truncated to 8 bits, so that one ADP data can be stored in one 8-bit RAM, since 12~16 bits require 16-bit RAM storage, therefore, The original 12~16bit storage of two 8-bit RAMs saves 1x of storage space. Overall, the baseband processor of a base station supports hundreds of terminals, saving 1 times of RAM storage space, greatly reducing power consumption and area of the chip, saving cost, supporting more users, and ensuring performance.

Specific embodiments of the present invention will be described below with reference to the accompanying drawings.

When the searcher processes the baseband signal, the baseband signal is descrambled and despreaded, the despread symbol data is descrambled, the pilot symbol depolarization is performed, and then the processed data is coherently accumulated and non-transformed. For the coherent accumulation operation, the ADP set obtained by coherent and non-coherent accumulation is subjected to the truncation operation, and the truncated data is subjected to IIR (infinite impulse response) filtering and threshold detection, and the maximum value of the energy path and the noise can be detected in the threshold detection. Mean value and energy threshold for subsequent signal processing. In this embodiment, the maximum value of the energy path or the noise mean value is taken as the intercept parameter of the next truncation. The following takes the maximum value of the energy path as the intercept parameter as an example. As shown in 1, the method includes:

101: The searcher in the baseband processor performs related operations on the real part and the imaginary part of the baseband signal and the scrambling code to obtain descrambled data;

Step 102: The searcher performs correlation operation on the data descrambled by the baseband signal and the spreading code to obtain despread data.

103: The searcher performs a coherent accumulation operation on the data of the baseband signal descrambled and despread, and accumulates the real part and the imaginary part respectively;

104: The searcher performs modulo and accumulation operations on the coherently accumulated symbol data to obtain a non-coherent accumulated node, that is, an ADP set;

The above step 101 104 uses the method in the prior art to finally obtain an ADP set.

105: The searcher intercepts the ADP set, and the truncation parameter uses the maximum value of the energy path obtained by the previous threshold detection, and intercepts the maximum value of the energy path from the ADP set and the total 8~12 bits downward. As sampling data;

For the first sampled baseband signal, since the maximum value of the energy path has not been obtained, the fixed intercept method can be used to intercept 12~16 bits of data for storage, so as to facilitate signal search. And the door ^ ^ measured to get the maximum value of an energy path.

The ADP set obtained after coherent and non-coherent accumulation uses a fixed bit width of 16 bits. The dynamically intercepted 8-12 bits of sampled data are determined by the maximum value of the energy path, and the maximum value of the energy path is the highest bit of the sampled data.

106: After the searcher uses the maximum value of the energy path to complete a truncation, when truncating the subsequent ADP set, according to the maximum value of the previous energy path, according to the highest and lowest bits of the previously intercepted sample data. , the range of the interception is obtained, and the sampling data of the current time is obtained, so that the previous bit of the highest bit of the sampled data is a saturated bit;

The interception range refers to the highest and lowest bits of the sampled data intercepted and the intermediate bits. The translation of the interception range (ie, how to translate the range of values) can be optimally selected based on the simulation model based on the actual conditions of the system. In this embodiment, the interception range is translated as follows: When the maximum value of the previous energy path is between 192 and 256, the interception range is shifted to the left by one bit, that is, the sampled data of the current interception is relatively intercepted. The sampled data is shifted to the left by one bit as a whole.

When the maximum value of the previous energy path is between 96 and 192, the interception range does not change.

When the maximum value of the previous energy path is between 48 and 96, the interception range is shifted to the right by one bit. When the maximum value of the previous energy path is between 24 and 48, the interception range is shifted to the right by two. When the maximum value of the previous energy path is between 12 and 24, the interception range is shifted to the right by three positions. When the maximum value of the previous energy path is between 6 and 12, the interception range is shifted to the right by four positions. When the maximum value of the previous energy path is between 3 and 6, the interception range is shifted to the right by five digits. When the maximum value of the previous energy path is between 1 and 3, the interception range is shifted to the right by six bits. When the maximum value of the previous energy path is between 0 and 1, the interception range is shifted to the right by seven bits. In addition, the present invention can also use the noise mean value obtained from the previous threshold detection as the interception parameter, and intercept the total value of the noise average from the ADP set and the upward total of 8 to 12 bits, as sampling data, and complete the intercept using the noise mean value. After performing the truncation of the subsequent ADP set, according to the previous noise average value, according to the highest and lowest bits of the last intercepted sample data, the interception range is translated, and the adopted data is obtained, so that the lowest bit of the sampled data is the next one. The bit is the noise bit.

When the noise mean is used as the interception parameter, the translation rule of the intercept range can be based on the energy path. The magnitude relationship of the peak-to-average ratio of the maximum value and the noise mean is determined, and the ratio of the peak value of the maximum value of the energy path to the peak value of the noise mean is in the order of 10 orders of magnitude.

When the previous noise average is between 19 and 26, the interception range is shifted to the left by one.

When the previous noise average is between 10 and 19, the interception range does not change.

When the previous noise average is between 5 and 10, the interception range is shifted to the right by one bit.

When the previous noise average is between 2 and 5, the interception range is shifted to the right by two.

When the previous noise average is between 0 and 2, the interception range is shifted to the right by three digits.

2 is a block diagram of a baseband signal according to the present invention, comprising: a radio frequency module and a baseband processor, wherein the baseband processor includes a searcher;

The radio frequency module is configured to receive the radio frequency signal, demodulate the received radio frequency signal into a baseband signal, and send the signal to the baseband processor searcher;

The baseband processor searcher is configured to: perform signal processing on the baseband signal to obtain an ADP set; perform truncation on the ADP set, and use the maximum value of the energy path obtained from the last threshold detection, and the maximum from the energy path. The value is intercepted a total of 8~12 bits as the sampling data; after the maximum interception of the energy path is completed, when the subsequent ADP set is truncated, according to the maximum value of the previous energy path, according to the previous interception The highest and lowest bits of the sampled data are translated into the interception range, and the current sampled data is obtained, so that the previous bit of the highest bit of the sampled data is a saturated bit.

The searcher can also be configured to: use the noise mean value obtained from the previous threshold detection as the interception parameter, and intercept 8~12 bits from the beginning of the noise average value of the ADP set as the sampling data, and complete the truncation after using the noise average value. When performing the truncation of the subsequent ADP set, according to the previous noise average value, according to the highest and lowest bits of the last intercepted sample data, the interception range is translated, and the adopted data is obtained, so that the last bit of the lowest bit of the sampled data is obtained. It is a noise bit.

For specific functions and other functions implemented by the searcher in the apparatus of the present invention, please refer to the description of the method content.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention. Industrial applicability

Compared with the prior art, the present invention can reduce the bit width of the signal and save the cost of the chip; and, the bit error rate of the method of the present invention can achieve the performance of the 3GPP (3rd Generation Partnership Project) and satisfy the function of the product.

Claims

Claim

1. A method for intercepting a baseband signal, comprising:

Signal processing of the baseband signal to obtain an amplitude delay profile ADP set;

The maximum value of the energy path obtained by the previous threshold detection is used as the intercept parameter, and the maximum value of the energy path of the ADP set and the total 8~12 bits of the ADP set are taken as sampling data; or, the last threshold is used. The detected noise mean value is used as a truncation parameter, and a total of 8~2 bits of the noise mean value of the ADP set and above are taken as sampling data.

2. The method of claim 1 further comprising:

After the truncation is performed by using the maximum value of the energy path or the mean value of the noise, when the truncation is performed again, the maximum value of the energy path obtained from the previous threshold detection or the noise mean value is the highest bit of the sampled data that was intercepted last time. The lowest bit, the translation interception range, so that the previous bit of the highest bit of the obtained sampled data is a saturated bit, or the last bit of the lowest bit is a noise bit.

3. The method according to claim 2, wherein the step of translating the interception range comprises: if the maximum value of the energy path obtained by the last threshold detection is between 192 and 256, the interception range is shifted to the left by one Bit; if between 96 and 192, the interception range is unchanged; if between 48 and %, it is shifted to the right by one bit; if between 24 and 48, it is shifted to the right by two digits; Between 12 and 24, shift to the right three digits; if between 6 and 12, shift to the right four digits; if between 3 and 6, shift to the right five digits; if between 1 and 3 , shifts six digits to the right; if between 0 and 1, shifts seven digits to the right.

4. The method according to claim 2, wherein the step of translating the interception range comprises: if the average value of the noise obtained by the last gate measurement is between 19 and 26, the interception range is shifted to the left by one bit; Between 10 and 19, the interception range is unchanged; if it is between 5 and 10, it is shifted to the right by one bit; if it is between 2 and 5, it is shifted to the right by two digits; if it is between 0 and 2 In between, shift the three digits to the right.

5. The method of claim 1 further comprising:

At the initial truncation, 12 16 bits of the ADP set are intercepted by the fixed truncation method as sampling data, and threshold detection is performed to obtain the maximum value of the energy path and the noise mean value.

6. A baseband signal intercepting apparatus, comprising: a radio frequency module and a baseband processor, wherein the baseband processor includes a searcher, wherein:

The radio frequency module is configured to receive a radio frequency signal, demodulate the received radio frequency signal into a baseband signal, and send the signal to the searcher;

The searcher is set to:

Performing signal processing on the received baseband signal to obtain an amplitude delay profile ADP set; and using the maximum value of the energy path obtained by the last threshold detection as a truncation parameter, and intercepting the maximum value of the energy path of the ADP set And the following 8~12 bits are used as sampling data; or, the noise average obtained by the last threshold detection is used as a truncation parameter, and the noise average value of the ADP set is taken as a total of 8~12 bits as Sample data.

7. The apparatus according to claim 6, wherein

The searcher is further configured to: after performing the truncation by using the maximum value of the energy path or the noise mean value, when the truncation is performed again, according to the maximum value of the energy path or the noise mean value obtained by the last threshold detection, according to the former The highest and lowest bits of the data sample that are intercepted are shifted, and the interception range is shifted so that the previous bit of the highest bit of the obtained sampled data is a saturated bit, or the last bit of the lowest bit is a noise bit.

8. The apparatus according to claim 7, wherein

The searcher is configured to translate the interception range by: if the maximum value of the energy path obtained by the last threshold detection is between 192 and 256, the interception range is shifted to the left by one bit; Between 192, the interception range is unchanged; if it is between 48 and 96, it is shifted to the right by one bit; if it is between 24 and 48, it is shifted to the right by two digits; if between 12 and 24, then Shifts three digits to the right; if between 6 and 12, shifts four digits to the right; if between 3 and 6, shifts five digits to the right; if between 1 and 3, shifts six digits to the right ; If it is between 0~1, it will shift to the right by seven digits.

9. The apparatus according to claim 7, wherein

The searcher is configured to translate the interception range by: if the average value of the noise obtained by the last threshold detection is between 19 and 26, the translation range is shifted to the left by one bit; if it is between 10 and 19 If the interval is between 5 and 10, shift to the right; if between 2 and 5, shift to the right; if between 0 and 2, Shift right three digits.

10. The apparatus according to claim 6, wherein The searcher is further configured to: when the initial truncation is performed, intercept 12 12 bits of the ADP set as sampling data by using a fixed truncation method, and perform threshold detection to obtain a maximum value of the energy path and a noise mean value.