KR20000052235A - High effective Apparatus and Method for sorting Signal searching result - Google Patents

Abstract

PURPOSE: A method for sorting high-performance signal search is provided to efficiently sort, without lowering a function of a code division multiple access(CDMA) signal searcher necessary for seeking an initial acquisition of CDMA signal and a multi-path signal, by sorting various energies of the multi-path according to sizes. CONSTITUTION: A method for sorting high-performance signal search, comprises the steps of: firstly comparing a present input value with an arbitrary pre-stored input value, and discriminating either variation or not of whether the present input value is increased according to the first comparison; deciding a point to sort the present input value with pre-inputted values according to the discrimination; storing the present input value, at the decided point; secondly comparing the stored present input value with an arbitrary value from the pre-input values; and sorting and storing the present input value and the pre-inputted values, according to the second comparison.

Description

High effective Apparatus and Method for sorting Signal searching result}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CDMA communication system, and more particularly, to a high performance signal search sorting device suitable for efficiently aligning a result of searching a CDMA signal and a signal search sorting method using the same.

In general, a CDMA communication system is capable of distinguishing multipath signals to provide excellent performance in urban environments.

In such a CDMA communication, a radio channel has a multi-path characteristic. In this radio channel, a radio path between a base station and a mobile station is a Rayleigh fading propagation component rather than a propagation component propagating through a line of sight. have.

Rayleigh fading is caused by a signal reflected from several features and a signal received at the same time with a slightly different delay time in various directions. When it cuts, it causes severe fading.

For this reason, in a CDMA communication system, signals received through multiple paths can be individually tracked by using a plurality of receivers called RAKE receivers.

The rake receiver receives signals from multiple paths at the same time, so that in the case of IS-95 CDMA, signals with delay times above 1 ms can be usefully combined.

As described above, a receiving apparatus of a CDMA communication system such as a rake receiver includes a CDMA signal searching apparatus so as to search pilot signals for initial acquisition and multipath signal searching of the CDMA signals.

At this time, each base station uses its own PN code as a pilot signal, and this PN code is used to distinguish several base station signals received at the mobile station.

The mobile station extracts the corresponding pilot signal by calculating a correlation between the signal received from the base station and the PN codes in order to search for the base station to which the mobile station belongs.

The CDMA signal retrieval apparatus constantly searches for other better path signals not only during the initial synchronization of the CDMA signal but also during normal signal reception.

Such a CDMA signal search apparatus requires a process of sorting a plurality of signal paths found by searching the CDMA signals by energy magnitude.

However, conventionally, a low performance signal alignment device using a simple hardware structure or a high performance alignment device using a complicated hardware structure is used.

In particular, it is necessary to use complex digital circuits to quickly align the search results of CDMA signals, and software algorithms using a computing device such as a processor may be used for the sorting process. There is a problem that is not suitable for use as a device for sorting.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a high performance signal search sorting device having a relatively simple structure and sorting the energy of the various paths that search the initial synchronization of the CDMA signal and the search result of the multipath signal and the signal using the same Its purpose is to provide a search sorting method.

A feature of the high performance signal search alignment device according to the present invention for achieving the above object is, comparing the current input value with any previously stored input value, and determining whether the current input value is increased or decreased accordingly. Wow; Determining an alignment point for aligning the current input value with a plurality of previous input values previously stored according to the determination result; At the determined alignment point, storing the current input value; Comparing the stored current input value with any previous input value that is first output among the plurality of previous input values; And sorting and storing the current input value and the plurality of previous input values according to the comparison result.

Preferably, the step of determining the alignment point determines the alignment point as a point where the current input value is compared with any previously stored input value, and then the current input value is determined to increase and decrease.

In addition, the storing after the sorting compares the stored current input value with any previous input value that is output first, and when the current input value is larger than the previous input value that is output first, the plurality of previous input values. The current input value is further stored after shifting another previous input value of the stored storage bank, and the previously outputted previous input value is stored separately for comparison with the next input value. On the contrary, when the current input value is smaller than the previous input value that is output first, shifting another previous input value of a storage bank in which the plurality of previous input values are stored and then recalling the previous output value which is output first. Stored in a different location in the storage bank, the current input value continues to be stored in the current storage location for comparison with the next input value.

In addition, the signal search alignment procedure is repeatedly performed at predetermined intervals.

In addition, a feature of the high performance signal search sorting method according to the present invention for achieving the above object is to output a current input value, and compare the current input value with any previously stored input value and then the current input value A local maximum retrieval unit for determining an alignment point for aligning the current input value and a plurality of previous input values stored in advance by determining whether the current value is increased or decreased; And a maximum value sorter for sorting and storing the input values according to a result of comparing the current input value with the plurality of previous input values at the determined alignment point.

Preferably, the local maximum retrieval unit stores a comparison unit for comparing the current input value with any previously stored input value, and the previously stored arbitrary input value, and stores the current input value. A detection register for outputting this current input value to the maximum value alignment portion as input, and a latch portion and logical product for outputting a signal indicating the determined alignment point to the maximum value alignment portion in accordance with a comparison result of the comparison portion. The maximum alignment unit includes a register bank for storing the plurality of previous input values, a temporary register for temporarily storing a current input value output from the local maximum search unit, and a register bank in the register bank. First, a comparison unit for comparing any previous input value outputted with the current input value with the comparison unit And the input value is provided with a plurality of multiple addition to output in accordance with the.

In addition, the register bank includes a plurality of registers, and according to the comparison result of the comparator, after shifting each previous input value stored in the plurality of registers, the input value is stored in the register having the lowest rank. The comparator starts comparing the input values according to the output signal of the AND gate output from the local maximum searcher.

1 is a block diagram showing the configuration of a signal retrieval apparatus using the high performance signal retrieval arrangement and method according to the present invention;

Figure 2 is a block diagram showing the configuration of a high-performance signal search sorting apparatus according to the present invention.

* Description of the symbols for the main parts of the drawings *

100: local maximum search unit 200: maximum value sorting unit

110: search register 210: first multiple part

120: first comparison 220: temporary register

130: latch portion 230: second multiple parts

240: second comparison unit 250: register bank

Hereinafter, a preferred embodiment of a high performance signal search alignment device and a signal search alignment method using the same according to the present invention will be described with reference to the accompanying drawings.

1 is a block diagram showing the configuration of a signal retrieval apparatus using the high performance signal retrieval arrangement and method according to the present invention.

Referring to FIG. 1, the sequence circulator 23 stores the PN code generated by the pilot PN code generator 22 in a register and repeatedly cycles the PN code to the despreader 13.

The despreader 13 despreads the output of the decimator 10 by QPSK using the PN code repeated in the sequence circulator 23.

Thereafter, each I-channel signal and Q-channel signal that are QPSK despread is accumulated by a coherent method.

Here, the despreader 13 and the accumulators 14 and 15 together act as correlators, each of which accumulates an adder (not shown) and a rotating register bank (not shown). The output values, i.e., correlation values, of the units 14 and 15 are input to the coherent register bank 16.

Thereafter, the energy calculator 17 calculates energy values, which are vector amplitudes of the I-channel signal and the Q-channel signal, from the signals sequentially stored and output in the coherent register bank 16, and these energy values are the third accumulated values. In section 18, it accumulates in a noncoherent manner.

The noncoherent register bank 19 stores the accumulated energy value, and the search result processor 20 uses the stored energy value to detect the presence or absence of a signal.

In order to realize the high-performance signal retrieval apparatus described so far, a process of sorting the accumulated energy values by size is required.

Figure 2 is a block diagram showing the configuration of a high performance signal search alignment device according to the present invention.

Referring to FIG. 2, the proposed high performance signal search sorting apparatus is used in the search result processor shown in FIG.

The illustrated high performance signal search sorting device is largely composed of a local maximum detector 100 and a maximum value sorting unit 200.

The local maximum search unit 100 may include a search register 110 for storing an input energy value, and a first comparison unit for comparing a current input energy value with a previous energy value stored in the search register 110. 120 is basically provided.

In the local maximum search unit 100 that obtains the local maximum value, the first comparison unit 120 compares the energy value previously input and stored in the search register 110 with the energy value currently input.

At this time, if the output of the first comparison unit 120 is positive ('0'), it indicates that the energy value input to the local maximum search unit 100 is increasing, and if it is negative ('1'), the current local Indicates that the energy value input to the maximum search unit 100 is decreasing.

Here, in order to find the local maximum value, it is necessary to find a point where the current input energy value increases and decreases. Therefore, the local maximum value is obtained at the point where the output of the first comparator 120 changes from '0' to '1'. A latch 130 and an AND gate are used for this purpose.

When the local maximum value is obtained from the local maximum search unit 100, the maximum value sorter 200 performs a sorting operation.

The maximum value sorter 200 compares the energy values input to the search register 110 of the local maximum search part 100 with the previous energy values already sorted and stored, and then temporarily registers 220 and the second necessary values. The comparator 240 is provided and has a register bank 250 that stores the newly sorted result.

Hereinafter, the operation of the maximum value alignment unit 200 will be described in more detail.

First, the previous local maximum values are stored in the register bank 250 after being sorted, and the current local maximum value obtained by the local maximum search unit 100 is temporarily stored through the first multi-unit (MUX1) 210. 220).

Thereafter, the second comparison unit 240 compares the current local maximum stored in the temporary register 220 with the previous local maximum stored in the first register of the register bank 250.

At this time, if the previous local maximum value of the first register is greater than the current local maximum value of the temporary register 220, the current local maximum value input from the search register 110 of the local maximum search unit 100 is It is stored in the temporary register 220 as it is, and the previous local maximum value of the first register is stored after being fed back to the fourth register of the register bank 250 through the second multiplier 230.

Accordingly, the previous local maximum values stored in the second register, the third register and the fourth register of the register bank 250 are shifted to the first register, the second register and the third register, respectively.

However, as a result of the comparison, if the current local maximum value of the temporary register 220 is greater than the previous local maximum value of the first register, the current local maximum value of the temporary register 220 is passed through the second multiple part 230. And stored in the fourth register of 250.

At this time, the previous local maximum values stored in the second register, the third register, and the fourth register of the register bank 250 are shifted to the first register, the second register, and the third register, respectively. The previous local maximum value stored in the one register is stored in the temporary register 220 through the first multiple part 210.

The operation of the high performance signal search sorting apparatus described so far is a sorting procedure performed for one period, and the sorting procedure is repeatedly performed.

As described above, according to the high-performance signal search sorting apparatus of the present invention and the signal search sorting method using the same, the effective sorting process can be performed quickly without degrading the performance of the CDMA signal searching apparatus required to find the initial synchronization and multipath signal of the CDMA signal. Can be done in time.

In addition, it has the effect of high performance while being implemented in a relatively simple hardware structure.

Claims (7)

Comparing the current input value with any previously stored input value, and determining whether the current input value increases or decreases accordingly; Determining an alignment point for aligning the current input value with a plurality of previous input values previously stored according to the determination result; At the determined alignment point, storing the current input value; Comparing the stored current input value with any previous input value that is first output among the plurality of previous input values; And sorting and storing the current input value and the plurality of previous input values according to the comparison result. The method of claim 1, wherein the determining of the alignment point comprises: determining, as the alignment point, a point at which the current input value is increased and decreased after comparing the current input value with any previously stored input value. High performance signal search sorting method, characterized in that. The method of claim 1, wherein the storing after the sorting comprises: comparing the stored current input value with any previous input value that is output first, when the current input value is larger than the previous input value that is output first. After shifting another previous input value of a storage bank in which a plurality of previous input values are stored, the current input value is further stored, and the previously outputted previous input value is stored separately for comparison with the next input value. High performance signal search sorting method. The method of claim 1, wherein the storing after the sorting comprises: comparing the stored current input value with any previous input value that is output first, when the current input value is smaller than the previous input value that is output first. Shifting another previous input value of a storage bank in which a plurality of previous input values are stored, and then storing the previously output previous input value in another location of the storage bank, and comparing the current input value with a next input value. High-performance signal retrieval sorting method, characterized in that is continuously stored in the current storage. Outputs a current input value, compares the current input value with any previously stored input value, determines whether the current input value is increased or decreased, and then stores the current input value and a plurality of previous input values previously stored; A local maximum search section for determining an alignment point for aligning; And a maximum value sorting unit for sorting and storing the input values according to a result of comparing the current input value and the plurality of previous input values at the determined alignment point. The method of claim 5, wherein the local maximum search unit, A comparison unit for comparing the current input value with any previously stored input value; A detection register for storing any input value previously stored, and outputting the current input value to the maximum value sorter as the current input value is input; And a latch unit and an AND gate for outputting a signal indicating the determined alignment point to the maximum value alignment unit according to a comparison result of the comparison unit. The method of claim 5, wherein the maximum value alignment unit, A register bank for storing the plurality of previous input values; A temporary register for temporarily storing a current input value output from the local maximum search unit; A comparison unit for comparing the current input value with any previous input value first outputted from the register bank; And a plurality of multiple parts configured to output corresponding input values according to the comparison result of the comparison unit.