WO2008043291A1

WO2008043291A1 - Synchronization method and system in mobile communication

Info

Publication number: WO2008043291A1
Application number: PCT/CN2007/070753
Authority: WO
Inventors: Branislav Popovic; Fredrik Berggren
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2006-09-30
Filing date: 2007-09-21
Publication date: 2008-04-17
Also published as: CN101155021A

Abstract

A synchronization method in mobile communication is disclosed which predifines several weight factors and self-complementary sequences. The method includes the following steps: Commit weighted computing on one of the self-complementary sequences with said several weight factors, constitue the several weighted results into synchronization signal and send it to the receiver. The receiver commits efficient golay correlator matching on the received synchronization signal and synchronize with the transmitter with the synchronization signal. A synchronization system in mobile communication is also disclosed. The invention commits weighted computing on a self-complementary sequence with several weight factors and sends the weighted result as a synchronization signal to the receiver. Then the receiver commits efficient golay correlator matching and realizes synchronization with the transmitter according to the matching result.

Description

Synchronization method and synchronization system in mobile communication

Technical field

The present invention relates to mobile communication technologies, and more particularly to a synchronization method in mobile communication and a synchronization system in mobile communication. Background of the invention

In a mobile communication system such as an Orthogonal Frequency Division Multiplexing (OFDM) system or an Evolved Universal Terrestrial Radio Access (E-UTRA) system, the sender and the receiver are in time Synchronization with frequency is extremely important. The sender and the receiver can be network devices and terminals, respectively.

Taking the E-UTRA system as an example, according to the protocol, when synchronizing, the sender can send a P-SCH signal as a synchronization signal to the receiver through the primary synchronization channel (P-SCH), and the receiver can obtain and transmit through detection. Side synchronization. The P-SCH signal may be an OFDM signal or a time domain or a frequency domain signal.

Among various detection methods, the amount of calculation based on the copy-related sliding correlation method is large. If the sync signal is a periodic signal, it can be detected using a differential correlation method. However, the differential correlation method produces a wide correlation peak and is not suitable for accurate synchronization timing. In addition, synchronization between the receiver and the sender can also be achieved by a hybrid correlation method based on copy-based sliding correlation and differential correlation.

The key to implementing the above synchronization method is the P-SCH signal as a synchronization signal. However, there is currently no specific implementation of the synchronization signal in the E-UTRA protocol, and thus the synchronization between the receiver and the sender cannot be achieved. Summary of the invention

In view of this, the embodiments of the present invention provide a synchronization method in mobile communication, which can implement synchronization between a receiver and a sender.

The embodiment of the invention further provides a synchronization system in mobile communication, which can realize synchronization between the receiver and the sender.

In a synchronization method in mobile communication provided by an embodiment of the present invention, multiple weighting factors and complementary sequences are preset, including the following steps:

Performing a weighting operation on one of the complementary sequences by using the plurality of weighting factors, and combining the obtained plurality of weighting operation results to form a synchronization signal, and transmitting the result to the receiving side;

The receiver performs efficient Gray correlator matching on the received synchronization signal, and synchronizes with the sender according to the matching result.

The synchronization system in the mobile communication provided by the embodiment of the present invention includes: a sender and a receiver, where

The sender stores a plurality of preset weighting factors and complementary sequences; performing weighting operations on one of the complementary sequences by using the plurality of weighting factors, and tying the obtained plurality of weighting operation results to form a synchronization signal, and synchronizing The signal is sent to the receiver;

The receiving side receives the synchronization signal from the sender; performs the high-efficiency gray correlator matching on the synchronization signal, and synchronizes with the sender according to the matching result.

It can be seen from the above technical solutions that the technical solutions of the embodiments of the present invention have the following beneficial effects:

The weighting operation is performed on a complementary sequence by using a plurality of weighting factors, and the obtained sequence of the plurality of weighting operation results is cascaded as a synchronization signal, and sent to the receiver, and the receiver performs an efficient gray correlator on the synchronization signal (Efficient) Golay Correlator,

EGO matching, synchronization with the sender is achieved based on the matching result. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exemplary flowchart of a synchronization method in mobile communication according to an embodiment of the present invention. 2 is a structural diagram of a synchronization system in mobile communication according to an embodiment of the present invention.

FIG. 3 is a flowchart of a synchronization method in mobile communication according to an embodiment of the present invention. Mode for carrying out the invention

The present invention will be further described in detail below with reference to the accompanying drawings.

In the embodiment of the present invention, a complementary sequence is weighted by a plurality of weighting factors, and the obtained sequence of the plurality of weighted operation results is cascaded as a synchronization signal to the receiver; the receiver further implements and transmits according to the synchronization signal. Side synchronization.

The complementary sequence performing the weighting operation is a binary complementary sequence or a complex value complementary sequence in a pair of complementary sequences; the pair complementary sequence and the weighting factor are preset; and the synchronization between the receiver and the sender is time-frequency synchronization.

The synchronization system in the mobile communication in the embodiment of the present invention includes: a sender and a receiver, where

The sender stores a plurality of weighting factors and complementary sequences that are preset; and performs weighting operations on one of the preset complementary sequences by using a plurality of weighting factors set in advance, and cascades the obtained plurality of weighting operation results to form a synchronization signal, and Sending a synchronization signal to the receiver;

The receiving side receives the synchronization signal from the sender; performs the high efficiency Gray correlator matching on the synchronization signal, and synchronizes with the sender according to the matching result.

In the above system, the receiver performs efficient Gray correlator matching on the received synchronization signal according to the stored complementary sequence; the receiver further obtains a delay for implementing synchronization according to the efficient Gray correlator matching result and the stored weighting factor. The sender and the receiver can For network devices and terminals. The complementary sequence and the weighting factor stored by the receiver are the same as the complementary sequence and the weighting factor constituting the synchronization signal, respectively.

FIG. 1 is an exemplary flowchart of a synchronization method in mobile communication according to an embodiment of the present invention. As shown in FIG. 1, the synchronization method in mobile communication in the embodiment of the present invention includes the following steps:

Presetting multiple weighting factors and complementary sequences; wherein the preset complementary sequences may be a pair of complementary sequences;

Step 101: Perform weighting operation on one of the preset complementary sequences by using a plurality of weighting factors set in advance, and cascade the obtained plurality of weighting operation results to form a synchronization signal, and send the result to the receiving party;

Step 102: The receiver performs high-efficiency gray correlator matching on the received synchronization signal, and synchronizes with the sender according to the matching result.

In the above step 101, the process in which the sender cascades to form the synchronization signal may be expressed as: arbitrarily selecting a complementary sequence from the preset complementary sequence, copying the complementary sequence into multiples, and respectively generating the copy by multiple weighting factors After the plurality of identical complementary sequences are weighted, the plurality of weighted complementary sequences are sequentially arranged, that is, cascaded to form a sequence as a synchronization signal; the sender may send a sequence as a synchronization signal to the P-SCH. receiver.

In the above process, the receiver performs high-efficiency Gray correlator matching on the received synchronization signal according to one of the preset complementary sequences, and the complementary sequence for performing the efficient Gray correlator matching is the same as the complementary sequence in the synchronization signal.

The sequence used to achieve synchronization, that is, the synchronization signal, can be expressed as: Synchronization signal = [0^ A, CI X A, ··· ··· , CM-1 A] ,

Wherein A is a complementary sequence of length N in a pair of complementary sequences; CO, C1, ..., CM-1 are M weighting factors; the weighting factor and complementary sequence A are also stored at the receiving side. If A is a binary complementary sequence, that is, a Gray complementary sequence, the weighting factor is correspondingly binary 1 or -1, which enables the synchronization operation of the receiver and the sender.

The double-repetition structure of the synchronization signal (M=2) can maximize the frequency offset estimation range. Therefore, in order to effectively improve the detection at high Doppler frequencies, the segmentation of the synchronization signal can be continued with time domain repetition. Then, the resulting correlation values are non-coherently accumulated.

Hereinafter, the synchronization system in the mobile communication and the synchronization method in the mobile communication of the present invention will be described in detail with reference to specific embodiments.

In this embodiment, the mobile communication system is an E-UTRA system, the sender is a base station, the receiver is a terminal, and the synchronization signal is a P-SCH signal as an example.

2 is a structural diagram of a synchronization system in mobile communication according to an embodiment of the present invention. As shown in FIG. 2, the synchronization system in the mobile communication of the present invention includes: a base station 201 and a terminal 202.

The base station 201 further includes: a synchronization signal unit 211 and a modulation unit 212.

The synchronization signal unit 211 stores a plurality of weighting factors and complementary sequences that are preset. The weighting operation is performed on one of the preset complementary sequences by using a plurality of weighting factors set in advance, and the obtained plurality of weighting operation results are cascaded to form a P- The SCH signal, and transmits the P-SCH signal to the modulation unit 212.

The P-SCH signal may be: a sequence formed by a weighted operation of a complementary sequence by a plurality of weighting factors, and expressed as: [CO x A, CI A, ..., CM-1 A ] „ where A is a complementary sequence of length N in a pair of complementary sequences preset; C0, C1, ..., CM-1 are preset M weighting factors.

The modulating unit 212 performs modulation processing on the received P-SCH signal, and transmits the processed P-SCH signal to the terminal 202.

The terminal 202 includes: a demodulation unit 221, a high efficiency Gray correlation unit 222, and a synchronization control unit 223.

The demodulation unit 221 performs demodulation processing on the P-SCH signal from the base station 201, and demodulates The subsequent P-SCH signal is sent to the efficient Gray correlation unit 222.

The efficient Gray correlation unit 222 stores the complementary sequence A; performs EGC matching on the received P-SCH signal according to the pre-stored complementary sequence, and transmits the matching result to the synchronization control unit 223.

The complementary sequence pre-stored in the efficient Gray correlation unit 222 is the same as the complementary sequence A constituting the P-SCH signal; the matching result is a sequence of correlation values.

The synchronization control unit 223 stores a plurality of weighting factors set in advance; using the matching result from the efficient gray correlation unit 222 and the weighting factor stored in advance, the delay for realizing synchronization is obtained.

The weighting factors stored in advance are the same as the weighting factors C0~CM-1 constituting the P-SCH signal; the working principle of the synchronization control unit 223 can be the same as the existing principle of acquiring the synchronization delay.

In the above system, the base station 201 and the terminal 202 may further include other functional units for signal amplification, mixing, etc.; when the base station 201 is the receiver, the high-efficiency Gray correlation unit and the synchronization unit may also be included; the terminal 202 may also be sent as a transmission. The square may include a sync signal unit.

Hereinafter, the synchronization method in mobile communication in the embodiment of the present invention will be described in detail. FIG. 3 is a flowchart of a synchronization method in mobile communication according to an embodiment of the present invention. As shown in FIG. 3, the synchronization method in the mobile communication of the present invention includes the following steps:

Step 301: Perform weighting operation on one of the preset complementary sequences by using a plurality of weighting factors set in advance, and use the obtained sequence of the plurality of weighting operation results as a P-SCH signal.

Before this step, a plurality of weighting factors and complementary sequences are preset; the preset complementary sequence may be a pair of complementary sequences.

In the above step 301, a complementary sequence used for the weighting operation is a complementary sequence A, The process of forming a P-SCH may be: first copying M complementary sequences A, and then performing weighting operations on the M complementary sequences A and the weighting factors C0~CM-1 respectively, to obtain M weighting operation results, that is, CO x A CM-l x A, and then M weighting operation results are connected in series to form a sequence as a P-SCH signal.

Wherein, the P-SCH signal can be expressed as:

P-SCH=[C0 A, CI X A, ··· ··· , CM-1 A] ,

Wherein, Α is a complementary sequence of a pair of complementary sequences of length ;; CO, C1, ..., CM-1 are preset M weighting factors; the weighting factor and the complementary sequence A is also stored in the terminal.

Step 302: The base station performs processing such as modulation on the P-SCH signal, and then sends the P-SCH signal to the terminal. In this step, the base station sends a sequence as a synchronization signal to the terminal through the P-SCH. Step 303: The terminal performs demodulation and the like on the received P-SCH signal.

Step 304: The terminal performs EGC matching on the P-SCH signal according to the pre-stored complementary sequence A. The complementary sequence A is the same; the matching result obtained by EGC matching is the correlation value sequence.

Step 305: The terminal obtains a delay for synchronization according to the matching result and the pre-stored weighting factor.

In this step, the weighting factors stored in advance are the same as the weighting factors C0 to CM-1 constituting the P-SCH signal.

The foregoing step 304 to step 305 is a process for the terminal to obtain a delay for implementing synchronization, and the process of obtaining the delay may be the same as the existing acquisition delay process.

In this embodiment, the terminal may be the sender and the base station may be the receiver. In this case, the synchronization between the receiver and the sender may be implemented by the above procedure.

In this embodiment, the mobile communication system is an E-UTRA system, and the technical party of the present invention. The case is also applicable to other mobile communication systems such as OFDM systems and WCDMA systems.

The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A synchronization method in mobile communication, characterized in that a plurality of weighting factors and complementary sequences are set in advance, and the method comprises the following steps:

2. The method according to claim 1, wherein the preset complementary sequence is: a pair of mutually complementary sequences;

Performing a weighting operation, and merging the obtained plurality of weighting operation results into a synchronization signal is: arbitrarily selecting one complementary sequence from the pair of complementary sequences, copying the selected complementary sequence into multiple, and respectively passing multiple weighting factors The plurality of complementary sequences generated by the copy are weighted, and the weighted complementary sequences are sequentially arranged to form a sequence as a synchronization signal.

3. The method according to claim 1, wherein the receiving party performs high efficiency Gray correlator matching on the received synchronization signal to: perform efficient gray correlation on the received synchronization signal according to a pre-stored complementary sequence. The matching is performed, and the pre-stored complementary sequence is identical to the complementary sequence in the synchronization signal.

The method according to claim 1 or 3, wherein the matching result is: a sequence of correlation values obtained by performing high efficiency Gray correlator matching on the synchronization signal;

The synchronizing with the time-frequency obtained by the sender according to the matching result is: obtaining a delay for implementing synchronization by using a correlation value sequence obtained by matching the high-efficiency Gray correlator and a pre-stored weighting factor, the pre-stored weighting factor and synchronization The weighting factors in the signal are the same.

5. The method of claim 1, 2 or 3 wherein the complementary sequence is a binary complementary sequence.

6. The method of claim 5 wherein the weighting factor is a binary number.

7. The method according to claim 1, wherein the sender is a base station, and the receiver is a terminal.

A synchronization system in a mobile communication, comprising: a sender and a receiver, wherein

9. The system according to claim 8, wherein the receiving party comprises: an efficient Gray correlation unit and a synchronization unit, wherein

The efficient Gray correlation unit stores the preset complementary sequence; performs efficient Gray correlator matching on the received synchronization signal according to the stored complementary sequence, and sends the matching result to the synchronization unit, where the stored complementary sequence and the synchronization signal are complementary The sequence is the same;

The matching result is: a sequence of correlation values obtained by performing high efficiency Gray correlator matching on the synchronization signal;

The synchronization unit stores a plurality of preset weighting factors; obtaining a delay for implementing synchronization according to a correlation value sequence from the efficient Gray correlator and a stored weighting factor, the stored weighting factor being the same as the weighting factor in the synchronization signal .

The system according to claim 8 or 9, wherein the sender is a base station and the receiver is a terminal.