KR100354414B1 - Apparatus and method for acquiring initial synchronous in correlator - Google Patents

Abstract

The present invention provides an apparatus and method for acquiring an initial synchronization of a correlator. The present invention includes a timing generator for generating a plurality of load signals with respect to a reference period of a received signal; A parallel PN code generator for receiving a plurality of load signals from the timing generator and generating a plurality of PN codes for a reference period; A pilot signal detector for receiving a plurality of PN codes generated by a parallel PN code generator, comparing the received signals with the received signals, and integrating the result by a predetermined integration period to detect energy of the received signal; A signal discriminating unit for determining whether synchronization has been acquired by comparing the energy of the received signal detected by the pilot signal detecting unit with a set expected value; Receiving the synchronization acquisition decision result of the signal determination unit, and controlling the timing generator, the parallel PN code generator, and the pilot signal detector, respectively, to generate a new PN code for synchronization acquisition when synchronization of the received signal is not achieved. When the control is performed and the synchronization is achieved, the processor unit aligns the energy magnitude and position information of the plurality of received signals detected in the repetitive synchronization state to find the position having the maximum energy. By doing so, you have a huge advantage over hardware complexity and performance.

Description

Apparatus and method for acquiring initial synchronous in correlator}

The present invention relates to an initial synchronization acquisition device and a method of the correlator, and in particular, the initial synchronization acquisition device of the correlator to enable a high-speed synchronization while using the correlator to have a significant advantage compared to the complexity and performance of the hardware and It's about how.

In general, a correlator is an apparatus used to separate weak information signals from noise by approximating a mathematical correlation function, and includes an autocorrelator, a cross correlator, and a serial correlator.

1 is a block diagram of an apparatus for acquiring an initial synchronization of a conventional correlator.

As shown therein, an analog / digital converter 1 for converting an input analog signal into digital; A matched filter unit (2) for receiving a signal output from the analog-to-digital converter (1) and a signal from the PN code control unit (4) to find a matching signal and detecting a pilot signal; A signal discriminating unit (3) for discriminating a signal output from the matched filter unit (2); A PN code control unit (4) for outputting a signal for controlling the PN code to find a matched signal in the matched filter unit (2); The processor 5 is configured to control the PN code control unit 4 and the matched filter unit 2 by receiving a signal from the signal discriminating unit 3.

The operation of the conventional apparatus configured as described above is as follows.

First, the conventional configuration basically includes a method of using a correlator that performs the same function and an initial synchronization acquisition using a matched filter.

So, the method using correlator is composed of hardware, but its configuration is simple, but it has one synchronization for a given integration length time, and as a result, it is difficult to obtain fast synchronization.

Synchronous acquisition using a matched filter also increases hardware complexity but has a significant advantage in high-speed synchronization acquisition, while increasing the complexity of hardware forces the use of a finite length filter for the entire received pilot signal. There have been many problems with its implementation and economics.

That is, in case of using a serial correlator, correlation energy is detected every 255 chips or 511 chips depending on how many chip sections energy is used for the signal. Therefore, the PN signal is loaded every 20ms so that the PN of another base station can be found after the next 20ms. You can configure this in parallel or mixed rather than using a slow serial correlator to reduce initial sync acquisition time, but it will take a relatively longer time than using a matched filter.

Therefore, the problem in the prior art eventually ends in time, and the time taken for initial synchronization acquisition is a factor indicating the performance of the receiver. From this point of view, it is difficult to obtain high-speed synchronization when using the conventional correlator. do.

Accordingly, the present invention has been proposed to solve the conventional problems as described above, and an object of the present invention is to enable a high-speed synchronization while using a correlator, so that the correlator can have a great advantage compared to hardware complexity and performance. An initial synchronization acquisition device and a method thereof are provided.

In order to achieve the above object, the initial synchronization acquisition device of the correlator according to an embodiment of the present invention,

A timing generator for generating a plurality of load signals with respect to a reference period of the received signal; A parallel PN code generator for receiving a plurality of load signals from the timing generator and generating a plurality of PN codes for a reference period; A pilot signal detector for receiving a plurality of PN codes generated by the parallel PN code generator, comparing the received signals with the received signals, and integrating the result by a predetermined integration period to detect energy of the received signal; A signal discriminating unit for determining whether synchronization has been acquired by comparing the energy of the received signal detected by the pilot signal detecting unit with a set expected value; Receiving the synchronization acquisition decision result of the signal determination unit, the timing generator, the parallel PN code generator and the pilot signal detector are controlled respectively to generate a new PN code for synchronization acquisition when synchronization of the received signal is not achieved. It is characterized in that the technical configuration consists of a processor for locating and having the maximum energy by aligning the energy magnitude and position information of a plurality of received signals detected in a repetitive synchronization state when synchronization is achieved.

Initial synchronization acquisition method of the correlator according to an embodiment of the present invention to achieve the above object,

A first step of initializing parameters and registers and setting an integration length for obtaining PN seed and correlation energy of each PN generator; A second step of comparing the received energy with one of a plurality of PN codes generated according to the load signal generated by the timing generator after initialization and calculating a correlation energy and then comparing it with a set expected value; Calculating a correlation energy between a new PN code generated according to a next load signal and the received signal if the calculated correlation energy is smaller than the expected value; A fourth step of informing the processor that the initial synchronization is in a state where the calculated correlation energy is larger than an expected value and holding the corresponding PN generator to perform repetitive synchronization on the same PN code; Collecting the energy and position information detected during the repeated synchronization for the held PN code a plurality of times, and finding a maximum value among the collected plurality of energy values and determining that the synchronization is obtained at the position of the corresponding energy; Performing the steps is characterized by its technical configuration.

1 is a block diagram of an initial synchronization acquisition device of a conventional correlator;

2 is a block diagram of an initial synchronization acquisition device of the correlator according to an embodiment of the present invention;

3 is a detailed configuration diagram of a parallel PN code generation unit in FIG. 2;

4 is a timing diagram of a timing generator in FIG. 2;

5 is a flowchart illustrating a method for initially obtaining synchronization of a correlator according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

10: timing generator 20: parallel PN code generator

30: pilot signal detection unit 40: signal determination unit

50: processor unit

Hereinafter, an embodiment according to the technical concept of the initial synchronization acquisition device and method of the present invention correlator as follows.

Figure 2 is a block diagram of an initial synchronization acquisition device of the correlator according to an embodiment of the present invention.

As shown therein, a timing generator 10 for generating a load signal of the PN code to be applied to the correlator; A parallel PN code generator 20 which receives a load signal from the timing generator 10 and generates a plurality of PN code signals for correlation with a pilot signal (or a received signal) to be searched for; A pilot signal detector (30) for receiving a PN code generated by the parallel PN code generator (20) and comparing the pilot signal with a pilot signal to detect correlation energy; A signal discriminating unit (40) for determining whether synchronization has been acquired by comparing the energy of the pilot signal detected by the pilot signal detecting unit (30) with an expected value; Receives the determination result of the signal discrimination unit 40, controls the timing generator 10, the parallel PN code generator 20, and the pilot signal detector 30 to synchronize and obtain the pilot signal. It is composed of a processor unit 50 for generating a new signal required, and collecting energy and position information in a repetitive synchronization state.

FIG. 3 is a detailed configuration diagram of the parallel PN code generation unit in FIG. 2.

As shown therein, a plurality of PN generators 21 to 24 for loading PN seeds to generate PN codes; A counter unit 25 for receiving a load signal of the timing generator 10 and a hold signal output from the processor unit 50 and outputting a switching control signal; The switch unit 26 selects the PN codes from the plurality of PN generators 21 to 24 according to the switching control signal of the counter unit 25 and transmits the PN codes to the pilot signal detector 30.

5 is a flowchart illustrating a method for initially obtaining synchronization of a correlator according to an embodiment of the present invention.

As shown therein, a first step (ST11) of initializing a parameter, setting a length for obtaining each PN Seed and correlation energy to be found in each PN generating unit, and initializing necessary registers; By performing the correlation with the received signal by the load signal generated by the timing generator 10 after the first step, the energy is integrated, and the energy and the expected value obtained during the energy integration are compared. Second steps ST12 to ST13; A third step (ST14) of obtaining a correlation energy between a PN signal of a next PN generator and a received signal by a next Load signal if the obtained energy is smaller than an expected value; A fourth step (ST15 to ST18) of notifying the initial synchronization state, generating a Hold signal to the PN generation unit, resetting the PN, and performing repetitive synchronization with respect to the set PN when the obtained energy is larger than the expected value; If the energy obtained by repeating the predetermined number of times for the same PN is larger than the expected value, the fifth step (ST19 ~ ST22) to determine the lock by notifying the position and energy, sorting the stored energy and position information to find the maximum value Perform

Referring to the accompanying drawings, the operation of the initial synchronization acquisition device and the method of the correlator according to the present invention configured as described in detail as follows.

First, a correlator (not shown) is composed of a signal for finding a received signal and a register for obtaining correlation energy.

The timing generator 10 generates a pilot signal PN in a high speed correlator, and the parallel PN code generator 20 receives a load signal of the timing generator 10 and receives a plurality of PN code signals for a pilot signal to be found. Is generated, and the pilot signal detector 30 receives the PN code generated by the parallel PN code generator 20 and detects a pilot signal to be searched for from the input signal.

The signal discrimination unit 40 compares the signal found by the pilot signal detection unit 30 with the desired signal, checks the result, and transmits the result to the processor unit 50. In the processor unit 50, the timing generator 10, The parallel PN code generation unit 20 and the pilot signal detection unit 30 are controlled to generate a new signal for verifying and verifying the pilot signal and to determine the magnitude of the signal.

In addition, the storage device (not shown) stores a basic PN code.

Referring to the operation of the present invention in more detail as follows.

First, in order to detect a pilot signal used in a wireless receiver, a correlation characteristic of a PN is usually used. In the present invention, a plurality of PNs are successively applied to a basic correlator using the correlation characteristic, so that a desired signal among the PNs of several base stations is rapidly generated. Acquire.

First, a load signal of a signal to be searched is generated using a reference square signal used in a wireless transceiver. In the present invention, a reference signal for an n-times effect is generated using this signal. This signal is also used as an interrupt signal of the parallel PN code generation unit 20 and the processor unit 50, thereby enabling high-speed initial synchronization of the present invention. In other words, if you want to find the pilot signal to search through the reference signal, you can integrate as many times as you want and check the result, and when the energy value is low compared to the reference energy, load a new PN to search a lot of pilot information within the same time. This results in n times performance compared to correlators having the same structure.

The basic PN of the signal to be searched when the reference signal is generated is controlled by the processor unit 50 and is simultaneously generated according to the reference signal delay. Accordingly, the basic PN to be newly searched can detect the correlation energy at the same time that the reference signal is applied. The searched parallel PN code generation unit 20 generates the next PN to maximize the effect of the parallel PN code generation unit 20.

When the searched energy of the correlator becomes higher than the reference value through the signal discriminator 40, the first search is basically determined to be completed, and the correlation energy is obtained again to verify and verify. In this way, the position of the signal that has been completed until the verification verification process is sent to the code tracker to perform the code synchronization acquisition procedure. In case of failure, the new PN is loaded to perform the initial synchronization acquisition procedure again.

The correlation section of the correlator can be set by the processor unit 50 by (coherent correlation length) * (noncoherent correlation length) within a reference signal.

On the other hand, the matched filter shown in the conventional configuration is similar to the pilot signal detection unit 30, but the complexity of the implementation is greatly increased, so that when producing an ASIC (Applicable Specific Integrated Circuit), a large area and power consumption Thus, the pilot signal detector 30 of the present embodiment uses a relatively simple serial correlator, and its internal structure is the same as that of a conventional serial correlator, but only a length for performing a serial correlation operation, that is, an integration length. ) Is shorter than the total length of the PN code used in conventional serial correlators.

The pilot signal detector 30 integrates the result of comparing the input signal with the PN code generated by the parallel PN code generator 20 by a given integration length and then supplies the energy to the signal discriminator 40. Will be sent. The signal discrimination unit 40 compares this energy with the expected value to perform a lock determination.

The parts different from the conventional configuration are the parallel PN code generator 20 and the timing generator 10.

Thus, when the timing generator 10 is described, conventionally, the load signal, which is to be generated once during the reference period, is generated at the programmed period.

For example, in order to detect the PN signal to be repeated in a 20 ms period, conventionally, the PN input of the serial correlator is input one PN signal over 20 ms. By dividing the N PN signals, different synchronization signals are checked several times at the same time. That is, there is an advantage that the initial synchronization acquisition time is shortened by N times or more at the same time. A timing diagram for this is shown in FIG.

As illustrated in FIG. 3, the PN code generator 20 uses a PN code through a control signal of a processor and a control signal through a counter that increases according to load signals generated from the n PN code generators and the timing generator. It is supposed to generate.

Each PN signal generator is initially seeded to generate a different PN signal and is continuously generated as time passes. In the first synchronization, the counter does not increase in the repetitive synchronization state, and the PN is reset by the Hold signal and PN is generated. At this time, each PN code generator generates the same PN, but spaced apart by the OFFSET known to the user.

In the repetitive synchronization state, the processor unit 50 internally collects information on the size and location of energy, repeats a predetermined number of times, and then sorts based on the result to find a location having the maximum energy.

5 is a flowchart illustrating a method for initially obtaining synchronization of a correlator according to an embodiment of the present invention.

Therefore, the control flow diagram for performing this setups the lengths L1 and L2 for finding the PN Seed and correlation energy to be found for each PN generation unit at the time of parameter initialization and initializes the necessary registers (ST11).

Energy is integrated by the correlator with the received signal by the load signal generated by the timing generator 10. This length is shown as L1. When the energy obtained during this L1 is small compared with the expected value, the correlation energy between the PN signal of the next PN generation unit and the received signal is obtained by the next Load signal (ST12 to ST14).

In this case, if the correlation energy is higher than a certain expected value, the processor reports the initial synchronization status and the PN generator generates a Hold signal, which resets the PN signal until another load signal is generated and starts the repetitive synchronization for the reset PN. do. At this time, reset PN code generator and initialize counter (ST15 ~ ST18).

A repeated number of times is repeated for the reset PN to report the position and energy to the processor for energy above expected values. After performing all the repetition times, the processor sorts the stored energy and position information to find the maximum value and determines the lock (ST19 to ST22).

As such, the present invention enables synchronization acquisition at high speed while using a correlator to have a great advantage compared to hardware complexity and performance.

Although the preferred embodiment of the present invention has been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

As described above, the initial synchronization acquisition device and method of the correlator according to the present invention by adding a generator for generating a control signal and a reference signal to the surroundings through the structure of the existing correlator to enable high-speed initial synchronization acquisition Comparing the difficulty and economicality of implementation, it is easier to manufacture custom semiconductors because it is possible to obtain high-speed initial synchronization while lowering the complexity of the circuit when constructing custom semiconductors due to the improved correlator performance. The saving of overall gate count and the simplification of circuits lead to lower power consumption, making it possible to produce economical custom semiconductors.

Claims (3)

A timing generator for generating a plurality of load signals with respect to a reference period of the received signal; A parallel PN code generator for receiving a plurality of load signals from the timing generator and generating a plurality of PN codes for a reference period; A pilot signal detector for receiving a plurality of PN codes generated by the parallel PN code generator, comparing the received signals with the received signals, and integrating the result by a predetermined integration period to detect energy of the received signal; A signal discriminating unit for determining whether synchronization has been acquired by comparing the energy of the received signal detected by the pilot signal detecting unit with a set expected value; Receiving the synchronization acquisition decision result of the signal determination unit, the timing generator, the parallel PN code generator and the pilot signal detector are controlled respectively to generate a new PN code for synchronization acquisition when synchronization of the received signal is not achieved. And a processor unit for locating a maximum energy level by aligning energy magnitude and position information of a plurality of received signals detected in a repetitive synchronization state when synchronization is achieved. Device. The method of claim 1, wherein the parallel PN code generation unit, A plurality of PN generators for generating PN codes according to PN seeds set differently from each other; A counter unit configured to receive a load signal of the timing generator and a hold signal output from the processor, and output a switching control signal; And a switch unit for selecting the PN codes generated by the plurality of PN generation units according to the switching control signals of the counter unit and transmitting the selected PN codes to the pilot signal detection unit. A first step of initializing parameters and registers and setting an integration length for obtaining PN seed and correlation energy of each PN generator; A second step of comparing the received energy with one of a plurality of PN codes generated according to the load signal generated by the timing generator after initialization and calculating a correlation energy and then comparing it with a set expected value; Calculating a correlation energy between a new PN code generated according to a next load signal and the received signal if the calculated correlation energy is smaller than the expected value; A fourth step of informing the processor that the initial synchronization is in a state where the calculated correlation energy is larger than an expected value and holding the corresponding PN generator to perform repetitive synchronization on the same PN code; Collecting the energy and position information detected during the repeated synchronization for the held PN code a plurality of times, and finding a maximum value among the collected plurality of energy values and determining that the synchronization is obtained at the position of the corresponding energy; Initial synchronization acquisition method of the correlator, characterized in that performing the step.