WO2012151870A1

WO2012151870A1 - Peak search method and device

Info

Publication number: WO2012151870A1
Application number: PCT/CN2011/081295
Authority: WO
Inventors: 黎立煌; 戴冠新
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-05-06
Filing date: 2011-10-25
Publication date: 2012-11-15
Also published as: CN102769893A; CN102769893B

Abstract

Disclosed in the present invention is a peak search method comprising: a plurality of energy data is obtained and separately entered into multiple adders of a first comparator circuit; each adder of the first comparator circuit separately compares the entered energy data per se with energy data currently stored in a connected data register per se and updates said energy data stored in each data register; after having obtained and compared all the energy data to be searched, a second comparator circuit obtains the energy data stored in each data register within the first comparator circuit and compares said obtained energy data to get a peak value. Also provided in the present invention is a peak search device characterized by rapid peak searches, an ability to meet high throughput requirements of a vector processor, and simple and effective algorithms. In addition, the hardware is simple and easy to manufacture and the invention is small and low-cost.

Description

Peak search method and device

The present invention relates to a peak search technique, and more particularly to a peak search method and apparatus. Background technique

Peak search is often used in application scenarios such as cell search, multipath search, and slot synchronization. The speed requirement is relatively high. For example, in Long-Term Evolution (LTE), when a cell is initially searched, 15 4800 sequences are searched every 5 ms, and other processes require about 420 k clock cycles; when the neighbor search starts, 3 are performed every 5 ms. The 4800 sequence search may also have other tasks such as downlink reception, measurement, and neighborhood search.

The existing peak search circuit reads a single energy data each time, and compares the read energy data with the previously obtained maximum energy data until the energy data is read one by one to obtain the maximum energy data. Value, and need to perform forward and reverse scans repeatedly, find other maximum values. For example, Chinese patent application No. 200510098701.4 proposes a peak search in Wideband Code Division Multiple Access (WCDMA) system. The existing peak search method has low scanning efficiency and high power consumption, and cannot meet the requirements of a high amount of processor throughput. Summary of the invention

In view of the above, it is a primary object of the present invention to provide a peak search method and apparatus that can accommodate the high throughput requirements of vector processors.

In order to achieve the above object, the technical solution of the present invention is achieved as follows:

The present invention provides a peak search method, the method comprising:

Obtaining a plurality of energy data, respectively input into a plurality of adders of the first comparison circuit; Each adder of the first comparison circuit compares the energy data input to itself with the energy data currently stored in the data register connected to the first comparison circuit, and updates each data register in the first comparison circuit to save Energy data;

After performing the acquisition and comparison on all the energy data to be searched, the second comparison circuit acquires the energy data held by each data register in the first comparison circuit, and compares the acquired energy data to obtain a peak value.

In the above solution, before the obtaining the plurality of energy data, the method further includes: performing correlation operation processing and filtering operation processing on the acquired sampling data, and performing modulo operation processing, and the result of the modulo operation processing The real part is extracted, and the energy data is obtained and saved in a memory.

In the above solution, the memory stores a plurality of energy data per row;

The acquiring a plurality of energy data is: reading a row of energy data from the memory. In the above solution, the updating the energy data stored in each data register in the first comparison circuit includes:

When the adder compares the input energy data to the energy data currently stored in the data register to which it is connected, the adder replaces the input energy data with the energy data stored in the self-connected data register.

In the above solution, the method further includes:

When the adder compares and obtains that the input energy data is greater than the energy data currently stored in the register to which it is connected, the adder also replaces the address of the input energy data with the address register of the first comparison circuit connected to itself. The energy data address currently saved in .

In the above solution, before the obtaining the plurality of energy data, the method further comprises: clearing each of the data registers in the first comparison circuit and/or each address register in the first comparison circuit.

In the above solution, the second comparison circuit acquires each data in the first comparison circuit And storing the energy data, and comparing the obtained energy data to obtain a peak value, comprising: the adder in the second comparison circuit acquires energy data saved by each of the plurality of first comparison circuits, and The acquired energy data are compared with each other to obtain the largest energy data in the acquired energy data, and the obtained maximum energy data is taken as the peak value.

In the above solution, after the peak is obtained, the method further includes:

The adder in the second comparison circuit saves the obtained peak value to a data register in the second comparison circuit, and saves the address of the peak value to an address register in the second comparison circuit.

In the above solution, after the peak is obtained, the method further includes:

Verifying whether the number of peaks obtained reaches a preset peak number threshold, and if not, clearing the obtained peak value and one or more data of the left and right sides of the peak from all the energy data to be searched After zero, repeat the peak search; otherwise, end the current peak search.

The present invention also provides a peak search device, the device comprising: a read data control circuit, a first comparison circuit, and a second comparison circuit;

The first comparison circuit includes a plurality of adders, a plurality of data registers, the plurality of adders being connected to the plurality of data registers one by one; a data register for storing energy data; and an adder for inputting the own Comparing the energy data with the energy data currently stored in the data register to which it is connected, and updating the energy data stored in each of the data registers;

a read data control circuit, configured to acquire a plurality of energy data, and input to the plurality of adders of the first comparison circuit respectively;

a second comparison circuit, configured to acquire energy data saved by each data register in the first comparison circuit after performing the obtaining and comparing the energy data to be searched, and comparing the acquired energy data, Get the peak.

In the above solution, the device further includes: a memory and a vector processor, wherein the memory is configured to save all the energy data to be searched; a vector processor, configured to perform correlation operation processing and filtering operation processing on the acquired sampling data, perform modulo operation processing, extract a real part from a result of the modulo operation processing, obtain the energy data, and save the In memory.

In the above solution, the memory is further configured to store a plurality of energy data per row; and the read data control circuit is further configured to read a row of energy data from the memory. In the above solution, each adder of the first comparison circuit is further configured to replace the input energy data with the data connected by itself when the input energy data is greater than the energy data currently stored in the data register connected thereto. Energy data saved in the register.

In the above solution, the first comparison circuit further includes a plurality of address registers, configured to store addresses of the energy data, and are connected to the adder one by one;

The adder is further configured to replace the address of the input energy data with the energy data address saved in the address register to which it is connected when the input energy data is greater than the energy data currently stored in the register.

In the above solution, the second comparison circuit includes an adder and a data register, wherein the adder of the second comparison circuit is configured to obtain, after the obtaining, and comparing all the energy data to be searched, Energy data stored in each data register of the first comparison circuit, and comparing the acquired energy data to obtain a peak value, and saving the obtained peak value to a data register of the second comparison circuit;

The data register of the second comparison circuit is configured to save the peak.

In the above solution, the second comparison circuit further includes an address register for storing the address obtained to the peak value;

The adder of the second comparison circuit is further configured to save the address of the obtained peak value to an address register of the second comparison circuit.

In the above solution, the device further includes: a loop control circuit and a clear control circuit, wherein the loop control circuit is configured to verify whether the number of peaks obtained by the second comparison circuit reaches Go to a preset peak number threshold, if not, notify the clear control circuit to clear, and activate the read data control circuit, the first comparison circuit, and the second comparison circuit to repeat the peak search; otherwise, End the current peak search;

And a clear control circuit, configured to: when receiving the notification of the loop control circuit, clear a peak obtained by the second comparison circuit and one or more data of the left and right sides of the peak from the memory.

In the above solution, the clear control circuit is further configured to clear each address register in the first comparison circuit and/or each address register in the first comparison circuit.

The peak search method and device provided by the present invention reads a plurality of energy data every clock cycle, compares the read multiple energy data in parallel, and compares all the energy data in parallel, and compares them in parallel. The energy data is then compared to obtain the peak value, only the forward search is performed, and the forward and reverse directions are not required to be alternately performed, the pause is not required in the middle, the peak search speed is fast, and the vector processor high throughput rate can be applied, and The present invention finds one maximum value per scan, and finds n maximum values to cycle n times. The algorithm is relatively simple and effective, and the control is simple and effective; in addition, the peak search device of the present invention only needs an adder and a register to implement Simple and easy to implement, small in size and low in cost. DRAWINGS

1 is a flow chart showing the implementation of the peak search method of the present invention;

1 is a schematic structural diagram of a peak search system of the present invention;

3 is a schematic structural diagram of a data storage device in a peak search device according to an embodiment of the present invention; FIG. 4 is a schematic structural view of each column of a data memory in a peak search device according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a peak search module in a peak search device according to an embodiment of the present invention; FIG.

6 is a structural diagram of a first comparison circuit of a peak search module according to an embodiment of the present invention; Schematic. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic idea of the present invention is: acquiring a plurality of energy data each time, and comparing by a plurality of adders, and updating the saved energy data according to the comparison result; until all the energy data are acquired and compared, The stored energy data are further compared to obtain a peak value. Thus, the plurality of energy data are compared in parallel, the speed is fast, the peak search efficiency is high, and the vector processor high throughput rate can be adapted.

The peak search method of the present invention, as shown in FIG. 1 , may mainly include the following steps: Step 101: Acquire a plurality of energy data, which are respectively input into a plurality of adders of the first comparison circuit;

Step 102: Each adder of the first comparison circuit compares energy data input to itself with energy data currently stored in a data register connected to itself, and updates energy data stored in each data register;

Step 103: After performing the obtaining and comparing the energy data to be searched, the second comparison circuit acquires energy data saved by each data register in the first comparison circuit, and compares the acquired energy data. Get the peak.

Specifically, before acquiring the plurality of energy data in step 101, the method may further include: performing correlation operation processing and filtering operation processing on the acquired sampling data, and performing modulo operation processing, from the modulo operation processing The real part is extracted from the result, and the energy data is obtained and saved to the memory.

The memory can store a plurality of energy data in each row, and the plurality of energy data is obtained in step 101, specifically: reading a row of energy data from the memory.

Specifically, in step 102, each adder compares the input energy data with the energy data currently stored in the data register connected to the adder, and compares the input energy data with the self-connected Energy data currently stored in the data register When the adder replaces the input energy data with the energy data stored in the self-connected data register; when the adder compares that the input energy data is not greater than the energy data currently stored in the data register to which it is connected, Keep the energy data in the data register unchanged.

Here, when the adder compares that the input energy data is greater than the energy data currently stored in the register to which it is connected, the adder also replaces the address of the input energy data with the energy currently stored in the address register connected to itself. Data address.

In practical applications, each energy data has a corresponding address. For example, the energy data is stored at the address 0~999. When the energy data is read, the read address is generated. If one row stores 8 energy data, p=8, the first time the energy data at the address 0 is read. The second time is read from the energy data at address 8, the third time from the energy data at address 16, and so on, so when reading the energy data, the read energy data can be obtained. the address of.

Here, before acquiring the energy data, the method may further include: clearing each of the data registers in the first comparison circuit, and/or each address register in the first comparison circuit.

Specifically, in step 103, the adder in the second comparison circuit acquires energy data stored in each data register in the first comparison circuit, and compares the acquired energy data with each other to obtain the acquired energy data. The largest energy data in the middle, the maximum energy data obtained is taken as the peak value.

Here, after step 103, the method may further include: the adder in the second comparison circuit saves the obtained peak value to a data register of the second comparison circuit, and saves the address of the peak to the location Said in the address register of the second comparison circuit.

After the peak is obtained, the method may further include: verifying whether the number of peaks obtained reaches a preset peak number threshold, and if not, obtaining the peak value and one or more of the left and right sides of the peak The data is cleared from all the energy data to be searched, that is, from the memory of all the energy data to be subjected to the peak search processing, and then the above steps 101-103 are repeated until the number of peaks obtained reaches the preset peak value. Number threshold; otherwise, end Pre-peak search.

Correspondingly, the present invention further provides a peak search device, the device comprising: a read data control circuit, a first comparison circuit and a second comparison circuit; wherein the first comparison circuit comprises a plurality of adders, a plurality of data registers The plurality of adders are connected to the plurality of data registers one by one; the data register is configured to store energy data; and the adder is configured to input the energy data of the input data and the energy data currently saved by the data register connected thereto Comparing and updating the energy data stored in each of the data registers;

The device may further include: a memory and a vector processor, wherein the memory is configured to save all the energy data to be searched; and the vector processor is configured to perform correlation operation processing and filtering operation processing on the acquired sampling data. And performing a modulo operation process, extracting a real part from a result of the modulo operation process, and obtaining the energy data and storing the energy data in the memory;

Here, the memory is further configured to store a plurality of energy data per row; the read data control circuit is further configured to read a row of energy data from the memory.

The adders of the first comparison circuit are further configured to replace the input energy data with the data register connected to the data register when the input energy data is greater than the energy data currently stored in the data register connected to the data. Energy data.

Here, the first comparison circuit further includes a plurality of address registers for storing an address of the energy data, connected to the adder, and the adder is further configured to input the energy data larger than When the energy data currently stored in the register is described, the address of the input energy data is replaced with the energy data address stored in the address register to which it is connected. Specifically, the second comparison circuit includes an adder and a data register, where the adder of the second comparison circuit is configured to acquire the obtained after performing the obtaining and comparing all the energy data to be searched. Energy data stored in each data register of the first comparison circuit, and comparing the acquired energy data to obtain a peak value, and storing the obtained peak value in a data register of the second comparison circuit; A data register of the circuit for holding the peak.

Here, the second comparison circuit may further include an address register for storing an address of the obtained peak value; the adder of the second comparison circuit may further be configured to save the address of the obtained peak value to the second comparison The address register of the circuit.

In an actual application, the first comparison circuit may be divided into a plurality of comparison units, each comparison unit includes an adder, a data register and an address register, wherein the adder in each comparison unit determines that the input energy data is greater than the When the energy data currently stored in the data register in the unit is compared, the energy data currently stored in the data register is updated to the input energy data, and the energy data address currently stored in the address register in the comparison unit is updated to Enter the address of the energy data. Similarly, the second comparison circuit can include a comparison unit including an adder, a data register, and an address register, and the adder saves the address of the obtained peak value to the address register of the comparison unit, and the obtained The peak value is saved to the data register of the comparison unit.

The device may further include: a loop control circuit and a clear control circuit, wherein the loop control circuit is configured to verify whether the number of peaks obtained by the second comparison circuit has reached a preset peak number threshold, If not, notifying the clear control circuit to clear, and starting the read data control circuit, the adder, the register, and the second comparison circuit, repeating the peak search; otherwise, ending the current peak search; clearing the control circuit And, when receiving the notification of the loop control circuit, clearing a peak obtained by the second comparison circuit and one or more data of the left and right sides of the peak from the memory. In practical applications, the loop control circuit may include a register for recording the number of peaks currently obtained.

Here, the clear control circuit may be further configured to clear each address register in the first comparison circuit and/or each address register in the first comparison circuit.

Embodiment 1

In practical applications, the pre-peak search task is performed by a vector processor, and the peak search process can be implemented by a hardware accelerator.

As shown in FIG. 1, the peak search device may include: a radio frequency receiving module, a data memory, a vector processor, and a peak search module, wherein the radio frequency receiving module is configured to receive data sampled by the ADC, and store the obtained adoption data to a data processor; a vector processor, configured to read sample data from the data memory, process the read sample data, obtain energy data, and save the obtained energy data to a data memory; a peak search module, Used to read energy data from the data memory, perform peak search processing, find the required peaks, save the found peaks, and return to the vector processor.

Specifically, the radio frequency receiving module receives the data sampled by the ADC in the radio frequency chip, and stores the sampled data into the data memory, and the vector processor reads the sampled data from the data memory, and performs related operations and filtering operations on the sampled data. After the modulo operation process, the real part is extracted, energy data is obtained, and the obtained energy data is saved in the data memory; after the vector processor sets the parameter of the peak search module, the peak search module reads from the data memory. Take energy data, perform peak search processing, find peaks, and return to the vector processor.

In practical applications, the process of processing the sampled data by the vector processor may include: the vector processor reads the sampled data from the data memory in a pipeline manner, and performs the operations of correlating and filtering the downlink sampled data with the primary synchronization sequence (PSS). And storing the obtained operation result (including the correlation of the I channel, the filtered result, and the Q channel correlation, the filtered result) into the data memory, and performing the modulo operation processing, and then reading the correlation from the data memory And after filtering As a result, the modulo operation processing is performed, and then the real part is extracted from the result of the modulo operation processing to obtain energy data, and the obtained energy data is written in the data memory.

Wherein, after the vector processor performs the modulo operation processing according to the formula (1), the real part of the obtained result is energy data, and is stored in the lower 16 bits of the data memory, and the imaginary part of the obtained result is 0, and is stored in the data memory. The high 16 bits.

\r \= r · ?* = Re ² + Im ² ( 1 ) where, represents a complex signal, Re is the real part, Im is? The imaginary part. Originally, each bank stores p/2 data. After performing the compression processing of the real part, the vacancy of the imaginary part of the data is removed, and a bank of the data memory stores p energy data, thus not only compressing/saving data. The memory storage space, and in the subsequent peak search, the efficiency of reading energy data will be doubled, and the throughput of parallel search can be doubled. In practical applications, the vector processor can perform the above-described processing of the extracted real part by an instruction to extract the real part.

Specifically, in order to adapt to the throughput of the vector processor, the data memory has the following structural features: The data storage format is a complex energy ^{F = Re Im} , and a 32-bit unit is used to store a complex energy data, wherein the lower 16 bits are real Part, the upper 16 bits are imaginary parts; as shown in Figure 3, the memory width (width) is 16*P*4 bits (P is an even number greater than 0), divided into 4 warehouses (banks), each bank has P /2 32-bit memory cells, the vector processor can read one column of data of the memory at a time, that is, P*2 energy data. If the vector processor only performs operations such as correlation operations, filtering operations, etc., and does not extract the real part, and then writes the result back to the memory, then the result is still a column of memory with P*2 energy data, but each A 32-bit memory cell will hold the modulus of the complex energy, with the upper 16 bits being 0 and the lower 16 bits being the real part (not 0). In fact, the peak search contains the operation of extracting the real part, ie in correlation. After the operation and the filtering operation, the operation of extracting the real part is performed by extracting the instruction of the real part, and then the result is written back to the memory, then one column of the memory is stored (16*P*4)/16=P*4 energy data. , that is, one A 32-bit unit stores two energy data, and a bank can store P energy data, as shown in FIG.

The foregoing describes that the vector processor can access the same column of data of four banks of the memory at a time, and the peak search module can access one column of a bank of the memory at a time, that is, 16*P bits of data, that is, P energy data. (If the vector processor has not performed the operation of extracting the real part, then each time it is read or written is P/2 data).

In practical applications, the data memory may be a synchronous static memory (SSRAM). The vector processor is further configured to perform parameter setting on the peak search module. The peak search module performs peak search processing on the read energy data according to the parameter settings of the vector processor.

The peak search module can be implemented by a hardware accelerator, and can access the data memory, and each time 16*p bits of energy data is read out from the data memory, that is, p energy data is read, and each time, in a pipeline manner, The read energy data is subjected to a peak search. Finally, the results of each peak search are compared to find a peak, and in this cycle, n maximum values to be searched are found in the energy data, where n is an integer greater than zero.

Specifically, as shown in FIG. 5, the peak search module may mainly include: a software interface, a read data control circuit, a first comparison circuit, a second comparison circuit, a clear control circuit, and a loop control circuit.

Wherein, the vector processor writes the parameters to be configured into the software interface to configure parameters to the peak search module. The software interface can be one or more registers for holding the configured parameters.

The read data control circuit sends a read request and a read address signal to the data memory according to the data memory read/write sequence (protocol), and after receiving the p energy data returned by the data memory, respectively inputting the p energy data to the first Compare the p adders in the circuit.

As shown in FIG. 6, the first comparison circuit may include p adders, p data registers, and p address registers, wherein an adder is respectively connected to a data register, and an address The register, the adder and the data register are in one-to-one correspondence, the adder and the address register are in one-to-one correspondence, the data register and the address register are in one-to-one correspondence, and each adder compares the energy data sent by the read data control circuit with the data register connected to the data register The energy data in the comparison is compared, and based on the comparison result, it is determined whether to update the energy data in the data register and the address in the address register.

In practical applications, if a bank in the data memory stores p energy data, where p is an integer greater than 0, p energy data is read into the first comparison circuit at a time, in order to achieve parallel comparison, the first comparison circuit needs Contains p adders. It is also possible to adjust the number of adders in the first comparison circuit in accordance with the amount of energy data that is actually processed in parallel.

After the first comparison circuit compares all the energy data, the second comparison circuit is configured to acquire p energy data from p data registers in the first comparison circuit, and obtain the p data from the p address registers. The address of the energy data, compares the obtained p energy data, finds the peak, finds the address corresponding to the peak, and saves the found peak and the address of the peak.

The second comparison circuit may include an adder, a data register, and an address register, wherein the adder is configured to acquire p energy data and an address of the p energy data from the first comparison circuit, and The acquired p energy data is compared to find a peak; the data register is used to store the peak found by the adder, and the address register is used to store the address of the found peak.

Clearing a control circuit, configured to perform a clear operation on the data memory according to a result obtained by the second comparison circuit, specifically, to obtain a currently found peak, and m energy data of the left and right sides of the peak from the data memory Cleared in the middle.

The loop control circuit is configured to control the above-mentioned read data control circuit, the first comparison circuit, the second comparison circuit, and the clear control circuit to work cyclically to find a plurality of peaks.

The peak search module performs the process of peak search, and the specific process is as follows:

Step 0: The vector processor writes the peak search to be configured in the software interface of the peak search module. Cable parameters, configuring peak search parameters for the peak search module;

Specifically, the peak search parameter configured by the vector processor may include: a source data address src_data_addr indicating an energy data address to be read, a data length data_len to read the energy data, a peak number threshold n, The number of data to be cleared/masked on the left and right sides of the peak, the address dest_data_addr in the data memory for storing the maximum value, the parameter dest-sel for indicating whether it is stored in the register or the data memory.

In practical applications, the number of data to be cleared/shielded on the left and right sides of the peak is the empirical parameter. If the filtering effect is good or the signal-to-noise ratio of the RF signal is high, a smaller value can be set.

Step 1: At startup, the clear control circuit clears the p data registers in the first compare circuit and the p address registers.

Step 2: The read data control circuit verifies whether there is still unread energy data in the data memory. If yes, the p energy data is read from the data memory storing the energy data every clock cycle, and respectively input to In the p adders in the first comparison circuit, otherwise, proceed to step 4;

Specifically, the read data control circuit can verify whether the current read data cycle has reached data_len/p cycles, and if so, all energy data in the data memory has been read, otherwise, there is still no read. Energy data.

Step 3: p adders respectively compare the energy data received by themselves with the energy data currently stored in the data register to which they are connected, and if the received energy data is greater than the energy data in the data register, The received energy data replaces the energy data currently stored in the data register, and stores the address of the received energy data in an address register to which it is connected; if the received energy data is not greater than the data The energy data currently stored in the register is kept unchanged by the data currently stored in the data register connected thereto, and the address currently stored in the address register is kept unchanged, and the process returns to step 2;

Step 4: The second comparison circuit reads energy from p data registers in the first comparison circuit Data, obtaining an address of each read energy data from p address registers in the first comparison circuit; then, the second comparison circuit compares the read p energy data, and the p energy data The largest energy data is determined as a peak, the peak is found, and the address of the peak is found. Finally, the found peak and the address of the peak are saved to a specified position, such as saving the peak to the data for storing the peak. Register, save the peak address to the address register for storing the peak address, or save the found peak value and the address of the peak to the result area in the data memory for saving the peak, so that one round of scanning ends, Found 1 peak;

In practical applications, if the number of peaks to be searched is large, the searched peaks can be stored in the data memory. If the number of peaks to be searched is small, the searched peaks can be stored in the accessible result register. .

Step 5: Accumulate 1 and find the number of peaks found;

Here, the peak search module described above may further include: a register for holding a state parameter indicating a peak search process, and a register for saving the number of peaks found.

Each time the second comparison circuit finds a peak, the register holding the state parameter indicating the peak search process increments the number of peaks it holds. In practical applications, the register for saving the number of peaks found will accumulate the number of peaks saved by one after each cycle.

Step 6: The loop control circuit determines whether the saved peak number reaches the pre-configured "peak number threshold n", and if so, ends the current flow, otherwise proceeds to step 7;

Specifically, the loop control circuit obtains the number of peaks currently found from the register for saving the number of found peaks, and determines whether the number of peaks found reaches a preset peak number threshold, and if so, The peak search is ended, otherwise, the read data control circuit, the first comparison circuit, the second comparison circuit, and the clear control circuit are controlled to continue searching for the peak value.

Step 7: Clear the control circuit to the peak in the data memory, and the m on both sides of the peak The energy data is cleared and returns to step 1 to repeat the above process.

In the above process, the reading and comparison of the energy data is performed in a pipeline manner, and the p energy data are compared in columns and in parallel, without stopping in the middle, and the speed is fast; and, the main part of the peak search module is a plurality of adders, and more Data registers and multiple address registers, the circuit is simple, easy to implement, and takes up a small area.

Embodiment 2

In this embodiment, a process of performing cell search by applying the peak search method and apparatus provided by the present invention is described in detail.

In practical applications, in the field of spread spectrum communication, the mobile terminal needs to synchronize with the base station through cell search, and the synchronization refers to aligning the local scrambling code of the mobile terminal with the scrambling code of the received signal, and thus, moving The terminal can demodulate the data from the received signal.

Based on the peak search method of Embodiment 1, the process of performing cell search in WCDMA may include the following steps:

Step 1: The vector processor of the peak search device performs correlation operation and filtering on the PSC and the downlink sample data (that is, cumulatively averaging the correlation operations of a plurality of slots) to obtain energy values of a series of correlation operations. Storing the energy value of the correlation operation in a data memory of the peak search device, the peak search module of the peak search device reading the energy value of the correlation operation from the data memory, and finding the energy value of the correlation operation The peak in the middle, finally, the slot boundary is determined based on the found peak.

Step 2: The vector processor performs a correlation operation on the secondary synchronization sequence (SSC) and the downlink sampling data, and performs filtering (that is, cumulatively averaging the correlation operations of the plurality of frames) to obtain an energy value of the correlation operation, The energy value of the correlation operation is stored in the data memory, and the peak search module reads the energy value of the correlation operation from the data memory to find a peak value in the energy value of the correlation operation. Determine the frame boundary and scrambling code group according to the slot boundary determined in step 1, and the peak found in this step and the position of the peak. Group ).

Here, since the frame structure of WCDMA includes 15 time slots, each slot of the PSC is repeated once, and the SSC of each slot is different. Therefore, step 2 needs to be repeated 15 times, and each possible SSC (SSCo - SSC) ₁₄ ) Perform correlation operations with the downsampled data, and perform peak search on the energy values of the obtained correlation operations. According to the slot boundary determined in step 1, and the downlink sampling data and SSC in this step. - A sequence in the SSC ₁₄ is found after the correlation operation and the position of the peak, determining the frame boundary and the scrambling code group.

Here, the process of finding the peak from the result is the same as the process of performing the peak search in the first embodiment, and will not be described again.

Step 3: The vector processor uses a spread code of a common pilot channel (CPICH, Common Pilot Channel) and the determined scrambling code group, and each possible scrambling code and downlink in the scrambling code group The sampled signal is further correlated and filtered to obtain a series of energy values of the correlation operation, and the energy value of the correlation operation is stored in the data memory, and the peak search module reads the correlation operation from the data memory. The energy value, the peak value is found, the specific scrambling code and the phase of the scrambling code are determined, and thus the cell search in WCDMA is completed.

Here, the specific implementation process of searching for the peak value in each step is the same as the process of performing the peak search in the first embodiment, and details are not described herein again.

The process of performing cell search in LTE may include the following steps:

Step 1: The vector processor performs a sliding correlation operation and filtering on the PSC and the downlink sampling data to obtain a sequence of energy values of the correlation operation, and stores the energy value sequence of the correlation operation in the data memory, and the peak search module reads the correlation. The energy value of the operation, finds the peak value in the energy value of the correlation operation, and determines the slot boundary and the used PSC based on the found peak value.

Here, since there are 3 PSC sequences, which PSC is used specifically, it is necessary to repeat step 1 three times to determine.

Step 2: The vector processor will sequence each of the 168 SSCs (chip length is 62) Multiplying and summing the corresponding points of the 62 subcarrier data specified in the protocol, obtaining 168 results, storing the 168 results in the data memory, and the peak search module reading the 168 results to find the 168 The peak in the result. Based on the location of the peak found in this step and the used SSC, and the PSC used in step 1, the ID of the cell in which the mobile terminal is located is determined, and the scrambling code used by the cell is confirmed by the cell ID. At this point, the cell search process ends.

The above is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention.

Claims

Claim

A peak search method, the method comprising:

Obtaining a plurality of energy data, respectively input into a plurality of adders of the first comparison circuit; each adder of the first comparison circuit respectively inputs the energy data of the input and the energy data currently stored in the data register connected to itself Comparing and updating the energy data saved in each of the data registers;

2. The peak search method according to claim 1, wherein before the obtaining the plurality of energy data, the method further comprises:

After performing the correlation operation processing and the filter operation processing on the acquired sample data, the modulo operation processing is performed, and the real part is extracted from the result of the modulo operation processing, and the energy data is obtained and stored in the memory.

3. The peak search method according to claim 2, wherein

The memory stores a plurality of energy data per row;

The acquiring a plurality of energy data is: reading a row of energy data from the memory.

4. The peak search method according to claim 1, wherein updating the energy data stored in each of the data registers comprises:

The peak search method according to claim 4, wherein the method further comprises: adding, when the adder compares that the input energy data is greater than energy data currently stored by a register connected thereto, the adder The address of the input energy data is also replaced by the number A comparison circuit stores the energy data address currently stored in its own address register.

The peak search method according to claim 5, wherein before the obtaining the plurality of energy data, the method further comprises:

Each of the data registers in the first comparison circuit and/or each address register in the first comparison circuit is cleared.

7. The peak search method according to claim 1, wherein the second comparison circuit acquires energy data stored in each data register in the first comparison circuit, and compares the acquired energy data to obtain a peak value. , including:

The adder in the second comparison circuit acquires energy data stored in each of the plurality of first comparison circuits, and compares the acquired energy data with each other to obtain maximum energy data in the acquired energy data. The largest energy data is obtained as the peak.

The peak search method according to claim 7, wherein after the peak is obtained, the method further comprises:

The peak search method according to any one of claims 1 to 8, wherein after the peak is obtained, the method further comprises:

10. A peak search device, the device comprising: a read data control circuit, a first comparison circuit, and a second comparison circuit;

The first comparison circuit includes a plurality of adders, a plurality of data registers, the plurality of adders being connected to the plurality of data registers one by one; a data register for storing energy data; an adder, For comparing the energy data of the input itself with the energy data currently saved by the data register connected thereto, and updating the energy data stored in the data registers;

The peak search device according to claim 10, wherein the device further comprises: a memory and a vector processor, wherein

a memory, configured to save all the energy data to be searched;

a vector processor, configured to perform correlation operation processing and filtering operation processing on the acquired sampling data, perform modulo operation processing, extract a real part from a result of the modulo operation processing, obtain the energy data, and save the In memory.

12. The peak search device according to claim 10, wherein:

The memory is further configured to store a plurality of energy data per row;

The read data control circuit is further configured to read a row of energy data from the memory.

The peak search device according to claim 10, wherein each adder of the first comparison circuit is further configured to: when the input energy data is greater than energy data currently stored in a data register connected thereto, The input energy data replaces the energy data stored in the data register to which it is connected.

The peak search device according to claim 13, wherein the first comparison circuit further comprises a plurality of address registers for storing an address of the energy data, and being connected to the adder one by one;

The adder is further configured to replace the address of the input energy data with the address register of the connected address when the input energy data is greater than the energy data currently saved by the register. The stored energy data address.

The peak search device according to claim 10, wherein the second comparison circuit comprises an adder and a data register, wherein

An adder of the second comparison circuit, configured to acquire energy data saved by each data register in the first comparison circuit after performing the obtaining and comparing the energy data to be searched, and acquiring the acquired The energy data is compared to obtain a peak value, and the obtained peak value is saved in a data register of the second comparison circuit;

The peak search device according to claim 10, wherein the second comparison circuit further comprises an address register for storing an address of the obtained peak value;

The peak search device according to any one of claims 10 to 16, wherein the device further comprises: a loop control circuit and a clear control circuit, wherein

a loop control circuit, configured to verify whether the number of peaks obtained by the second comparison circuit reaches a preset peak number threshold, and if not, notify the clear control circuit to clear, and start the read data The control circuit, the first comparison circuit, and the second comparison circuit repeat the peak search; otherwise, the current peak search is ended;

The peak search device according to claim 17, wherein the clear control circuit is further configured to clear each address register in the first comparison circuit and/or each address register in the first comparison circuit. zero.