WO2013079028A1

WO2013079028A1 - General method for implementing synchronous transmission and reception of wireless communication test platform

Info

Publication number: WO2013079028A1
Application number: PCT/CN2012/085708
Authority: WO
Inventors: 魏坤; 葛晓光; 王浩文; 徐珏; 杨旸; 杨馨; 刘立刚; 熊勇
Original assignee: 上海无线通信研究中心
Priority date: 2011-12-02
Filing date: 2012-12-01
Publication date: 2013-06-06
Also published as: CN103139126A

Abstract

The present invention provides a general method for implementing synchronous transmission and reception of a wireless communication test platform. The method comprises: generating a ZC sequence of a trigger synchronization signal at a transmitter; adding the ZC sequence to the beginning of a data sequence to be transmitted, and transmitting the ZC sequence, together with data sequence to be transmitted, to a receiver; the receiver removing a synchronization header of the received signal to obtain the data sequence to be transmitted, the process of removing the synchronization header being: performing autocorrelation processing on the received signal to obtain an autocorrelation peak position, and performing cross-correlation on the received signal, with a starting position being the autocorrelation peak position, and the ZC sequence, to obtain a cross-correlation peak position, the cross-correlation peak position being the initial position of the trigger synchronization signal. In the present invention, the trigger signal is not transmitted inside a trigger line, but arrives near to data, and therefore the synchronization effect is less affected by the transmission distance and transmission interference; the judgment is not only based on the trigger level, thereby achieving high accuracy; no hardware setting is required, thereby achieving high universal applicability.

Description

General method for realizing transmission and reception synchronization of wireless communication test platform

The present invention relates to the field of wireless communication technologies, and relates to a synchronization method, and in particular to a general method for implementing synchronization of transmission and reception of a wireless communication test platform. Background technique

Forming and perfecting mobile communication standards is a complex process. First of all, a lot of research on the corresponding technology is needed to extract the corresponding theory. Secondly, technical simulation is carried out on the corresponding theory to verify the feasibility of theory and technology in the real environment; then the corresponding technology is real. test. In this process, a large number of research institutions and companies will participate in the exchange, discussion, and finally a set of complete standards will be formed by authoritative standards-setting bodies. In the process of forming mobile communication standards, simulation plays a very important role. At present, domestic simulation of key technologies for wireless communication is mostly realized by pure computer software. Although software simulation can reflect certain problems, it can not accurately reflect the real communication environment, and the actual results are still far from each other. The problem is to build a hardware simulation platform.

The hardware emulation platform uses hardware devices to perform more accurate simulations of transmitters, channels, and receivers, resulting in more realistic results. For the transmitter and receiver, modules that can generate true analog signals, such as the E4438c signal generator, the 89600 vector signal analyzer, etc., can be used. For the channel, the corresponding mathematical formula is used to approximate the electromagnetic signal to propagate in the real physical environment. With the advancement of technology, real channel emulators (such as EB's C8, F8, Spirent's SR5500, etc.) have been widely used at home and abroad. The simulation of the soft and hard combination using the channel simulator enables a more accurate approximation of the real physical environment with higher reliability.

In summary, it can be seen that the hardware simulation platform plays an important role in the testing process. However, in the process of building the hardware simulation platform, the channel emulator and the feeder are passed between the transmitting end and the receiving end, so the problem of unsynchronized transmission and reception is generated, which does not occur during the computer software simulation process. Consider the issue. In communication systems, different communication protocols have their own unique synchronization methods. For a multi-standard universal test platform, the workload of setting up synchronization modules for different standard communication systems is very large.

Now the synchronization of the transceiver is mainly implemented by hardware triggering and software processing of the reference signal. Hardware triggering means that the equipment provider connects each meter with a trigger line, and synchronizes between the instruments by trigger level transmission and reception. This synchronization method has the following disadvantages: 1) Since the trigger signal also passes through the trigger line transmission, there will still be an offset of individual digits after the trigger signal synchronization in high-speed data transmission, which will have a certain impact on the simulation results of the communication system with high synchronization requirements. ;

2) There are certain differences in the trigger synchronization of instruments of different test standards. Even if the trigger settings provided by different test equipment vendors under the same standard are not exactly the same, the setting of the trigger is a complicated task;

3) In the air interface test of the external field, due to the trigger line, the distance between the transceiver and the device is limited, which brings difficulties to the long-distance distance test.

Each communication standard has its own synchronization method. Generally, the position of the synchronization header is obtained by inserting a specified reference signal in the transmission sequence and performing correlation processing at the receiving end. However, the method of generating the reference signal of different communication systems and the insertion position and the processing method at the receiving end are quite different, which brings inconvenience to the multi-standard test platform. Therefore, there is an urgent need for a simple and versatile synchronization method that can implement a multi-standard test platform. Summary of the invention

In view of the above disadvantages of the prior art, an object of the present invention is to provide a general method for realizing transmission and reception synchronization of a wireless communication test platform, which is used to implement transmission and reception synchronization of various communication standard hardware simulation platforms.

To achieve the above and other related objects, the present invention provides a general method for implementing transmission and reception synchronization of a wireless communication test platform.

A general method for realizing transmission and reception synchronization of a wireless communication test platform, comprising:

Step 1: generating a trigger synchronization signal at the transmitting end, where the trigger synchronization signal is a ZC sequence; the ZC sequence is located at a front end of the data sequence to be transmitted, and is transmitted to the receiving end together with the data sequence to be transmitted;

Step 2: Perform desynchronization header processing on the received signal at the receiving end to obtain the to-be-transmitted data sequence. The process of the desynchronization header processing is:

Performing autocorrelation processing on the received signal to obtain an autocorrelation peak position;

The received signal with the autocorrelation peak position as a starting position is cross-correlated with the ZC sequence to obtain a cross-correlation peak position; the cross-correlation peak position is an initial position of the trigger synchronization signal.

As a preferred solution of the present invention, in step 1, the trigger synchronization signal further includes a zero sequence, and the zero sequence is located between the ZC sequence and the data sequence to be transmitted.

As another preferred solution of the present invention, after the zero sequence is added to the front end of the data sequence to be transmitted, the oversampling process is performed, and the ZC sequence is added to the front end of the oversampled sequence to form the trigger synchronization signal.

As a further preferred solution of the present invention, the sequence after the desynchronization header processing described in step 2 is subjected to down sampling. Have to wait for the data sequence.

In a second preferred embodiment of the present invention, in the second step, the autocorrelation process is: shifting the received signal; multiplying the shifted received signal by the received signal before shifting, and Sum in a window of preset width; slide the window back from the start end to a preset range to obtain a window corresponding to different sliding positions, that is, an autocorrelation result of the synchronization signal.

As a further preferred solution of the present invention, the general method for implementing transmission and reception synchronization of the wireless communication test platform further includes: performing phase correction on the initial phase deviation of the autocorrelation peak position according to an initial phase of the data being 0. As described above, the general method for realizing the transmission and reception synchronization of the wireless communication test platform according to the present invention has the following beneficial effects:

1) Since the general method described in the present invention is no longer simply relying on the trigger level for simple judgment, but using the correlation processing of the trigger signal (ZC sequence) for synchronization, the performance ratio of the synchronization method according to the present invention is triggered. The synchronization effect achieved by the level mode is better. The offset position is within one bit, which is smaller than the offset of the trigger level mode.

2) Since the trigger signal is not transmitted separately in the trigger line but arrives adjacent to the data, the effect of the synchronization is less affected by the transmission distance and the transmission interference.

3) Compared with the trigger mode and the synchronization mode of different standards, the advantage of the invention using the trigger signal for synchronization is that the operation is simple, and only the synchronization module needs to be added at the transmitting end of the algorithm test, and the receiving end can be implemented by adding the desynchronization module. It does not require complicated settings triggered by hardware, and is implemented independently of the equipment of the test platform, and has versatility and high practical value. DRAWINGS

FIG. 1 is a schematic flowchart diagram of a general method for implementing transmission and reception synchronization of a wireless communication test platform according to the present invention.

FIG. 2 is a schematic diagram of a specific process for generating a trigger synchronization signal according to Embodiment 2.

FIG. 3 is a schematic flowchart of a specific process of de-triggering a synchronization signal according to Embodiment 2.

Detailed ways

The embodiments of the present invention are described below by way of specific examples, and those skilled in the art can readily understand other advantages and effects of the present invention from the disclosure of the present disclosure. The invention may also be embodied or applied by other different embodiments, and the details in the specification may also be based on different viewpoints and applications without departing from the essence of the invention. God makes various modifications or changes. Please refer to the attached picture. It should be noted that the illustrations provided in this embodiment merely illustrate the basic concept of the present invention in a schematic manner, and only the components related to the present invention are shown in the drawings, instead of the number and shape of components in actual implementation. Dimensional drawing, the actual type of implementation of each component's type, number and proportion can be a random change, and its component layout can be more complicated.

In the wireless communication system, the test result of the hardware simulation platform is an important indicator that the algorithm module is applied to the real system. The hardware simulation platform can simulate the communication environment more realistically, and the simulation result is more convincing. However, due to the transmission line and various intermediate instruments in the hardware simulation implementation process, the synchronization of the transceiver is a problem that many hardware simulation platforms often encounter during the construction process. Therefore, in the use of the hardware simulation platform, it is necessary to use different communication. Different methods of standard implementation to achieve synchronization, the scope of the hardware simulation platform test and the efficiency of hardware simulation bring great losses, so the present invention proposes a general method for realizing the transmission and reception synchronization of the wireless communication test platform, the general method The problem of difficulty in transmitting and receiving synchronization of the hardware simulation platform is effectively solved, and the use range of the hardware test platform and the test efficiency of the hardware test system are increased. The invention conveniently realizes the synchronization of the transceiver end in the hardware test of the communication system of different standards.

The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings. Embodiment 1 This embodiment provides a general method for implementing transmission and reception synchronization of a wireless communication test platform. As shown in FIG. 1, the method includes the following steps:

Step 1: A trigger synchronization signal is generated at the transmitting end, where the trigger synchronization signal is a ZC sequence; the ZC sequence is located at a front end of the data sequence to be transmitted, and is transmitted to the receiving end together with the data sequence to be transmitted.

Further, the trigger synchronization signal may further include a zero sequence, the zero sequence being located between the ZC sequence and the to-be-transmitted data sequence.

Further, an oversampling process may be performed after adding a zero sequence at the front end of the data sequence to be transmitted, and a ZC sequence is added to the front end of the sequence after the oversampling process to constitute a transmission signal.

Step 2: Perform desynchronization header processing on the received signal at the receiving end to obtain the to-be-transmitted data sequence. The synchronization header refers to a zero sequence and a zc sequence added at the front end of the data sequence to be transmitted.

The process of the desynchronization header processing is:

Coarse synchronization positioning: performing autocorrelation processing on the received signal to obtain an autocorrelation peak position; the autocorrelation processing process is: shifting a received signal; and transmitting the shifted received signal and the received signal before shifting Perform corresponding multiplication and sum in a window of preset width; slide the window back from the starting end to a preset range to obtain a window corresponding to different sliding positions Port and, that is, the autocorrelation result of the received signal. According to the characteristic that the initial phase of the data is 0, the phase correction of the initial phase deviation of the autocorrelation peak position can also be performed.

Fine synchronization positioning: cross-correlating the received signal with the autocorrelation peak position as a starting position and the ZC sequence to obtain a cross-correlation peak position; the cross-correlation peak position is an initial position of the trigger synchronization signal . According to the characteristic that the initial phase of the data is 0, the phase correction of the initial phase deviation of the cross-correlation peak position can be performed.

The sequence of the data to be transmitted can be obtained by downsampling the sequence processed by the desynchronization header. The universal method for realizing the transmission and reception synchronization of the wireless communication test platform is applicable to the hardware simulation test platform of the wireless communication system, and conveniently solves various communication standards and various test instruments in the wireless communication system hardware simulation platform test process. Side synchronization issue.

The central idea of the present invention is to add a newly generated trigger signal before the hardware needs to transmit data. Unlike the conventional trigger level, the trigger signal is a ZC sequence, and the trigger signal is processed at the receiving end to finally find the data. Start bit. The general method for realizing the transmission and reception synchronization of the wireless communication test platform according to the present invention has the following beneficial effects:

3) Compared with the trigger mode and the synchronization mode of different standards, one advantage of the invention for using the trigger signal for synchronization is that the operation is simple, and only the synchronization module needs to be added at the transmitting end of the algorithm test, and the receiving end can be implemented by adding the desynchronization module. It does not require complicated settings triggered by hardware, and is implemented independently of the equipment of the test platform, and has versatility and high practical value. Embodiment 2

This embodiment provides a general method for implementing transmission and reception synchronization of a wireless communication test platform. Since the ZC sequence has a good autocorrelation, in the present embodiment, the trigger signal uses a 2048-point ZC sequence and is copied once to make a shift autocorrelation at the receiving end. The specific steps of the general method for realizing the transmission and reception synchronization of the wireless communication test platform according to the present invention are as follows:

At the transmitting end, a specific process for generating a trigger synchronization signal is shown in FIG. 2: In order to prevent inter-code interference caused to the transmission sequence after the added ZC sequence passes through the channel, the embodiment is to transmit a sequence (also referred to as data to be transmitted). Front end added 64 bit Zero, a 2048-point ZC sequence is added to the front end of the 64-bit zero, and the entire data sequence is represented as s(fc), which is transmitted from the transmitting end after amplitude adjustment.

s(k) is received at the receiving end by a channel emulator or wireless transmission, and the data received by the receiving end is represented as r(k). At the receiving end, the specific process of triggering the synchronization signal is shown in Figure 3. First, the received sequence r(fc) is shifted by 2048 bits to obtain r'(fc)=r(fc + 2048), and then r'( Fc) correspondingly multiplied with the unshifted receiving sequence r(fc) and at a width of

The window is summed in the window of 2048. The window slides from the starting end to the preset sliding range, that is, the initial search range is 40000, and the window corresponding to the different sliding positions is obtained, that is, the autocorrelation result of the receiving sequence is:

00∞

R(k)= ^r(k+i+2 )-r(k+i)

i=0

Since the ZC sequence described in this embodiment is data having a length of 2048 at both ends, after the autocorrelation, the previous ZC and the latter ZC overlap each other, so the maximum value of R(fc) is the initial obtained by the coarse synchronization. Position P _:

P = Position{Max{R(k)}} The initial position P is the position of the first data bit in the ZC sequence, and the result of the coarse synchronization positioning is obtained based on this position. In addition, the initial phase of the position of the first data bit can be obtained. Since the initial phase of the data should be 0, phase correction can be performed based on the initial phase deviation.

After the coarse synchronization is completed, the window range of the fine synchronization is set. In this embodiment, the coarse synchronization sequence (referring to the S(fc) starting with the initial position P) is set to 32 bits before and after the slide, and the sequence in the search window is marked as _r ^ff. ( ), cross-correlate _r ^ff ( ) with the local training sequence ZC to obtain relevant results:

64 4095

h = ∑ ∑ ZC (i) - r"(i + j)

j = i =

Since the number of ZC points is large, the performance of the cross-correlation is very good. After cross-correlation, a very significant correlation peak is obtained, and the exact initial position of the transmission sequence can be found based on the cross-correlation peak. As with coarse synchronization, phase correction can be performed based on the initial phase of the data. After performing the above operations, four times downsampling is performed to recover the required received data, and the transceiver is synchronized.

If the synchronization algorithm is not added, it only depends on the trigger synchronization. Due to the influence of the wires, there will be some deviation, resulting in poor results, which cannot achieve the purpose of testing. After observing the data of the receiving end, after adding the synchronization algorithm module, the transmitting and receiving end can be synchronously positioned within one bit, and a better result can be achieved. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value. The above-described embodiments are merely illustrative of the principles of the invention and its advantages, and are not intended to limit the invention. Modifications or variations of the above-described embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and scope of the invention will be covered by the appended claims.

Claims

A general method for implementing transmission and reception synchronization of a wireless communication test platform, wherein the general method for implementing transmission and reception synchronization of a wireless communication test platform includes:

Step 1: generating a trigger synchronization signal at the transmitting end, where the trigger synchronization signal is a ZC sequence; the ZC sequence is located at a front end of the data sequence to be transmitted, and is transmitted to the receiving end together with the data sequence to be transmitted; Step 2, at the receiving end Receiving a signal for performing desynchronization header processing to obtain the to-be-transmitted data sequence; the process of the desynchronization header processing is:

The received signal with the autocorrelation peak position as a starting position is cross-correlated with the ZC sequence to obtain a cross-correlation peak position; the cross-correlation peak position is an initial position of the trigger synchronization signal. The method for implementing the wireless communication test platform for transmitting and receiving synchronization according to claim 1, wherein: in step 1, the trigger synchronization signal further includes a zero sequence, and the zero sequence is located in the ZC sequence and the data to be transmitted. Between sequences. The general method for implementing the transmission and reception synchronization of the wireless communication test platform according to claim 2, wherein: the sampling sequence is added after the zero sequence is added to the front end of the data sequence to be transmitted, and the front end of the sequence after the oversampling process is increased. The ZC sequence constitutes the trigger synchronization signal. The general method for implementing the transmission and reception synchronization of the wireless communication test platform according to claim 3, wherein: the sequence after the desynchronization header processing described in step 2 performs downsampling to obtain a data sequence to be transmitted.

The general method for implementing the synchronization of the wireless communication test platform according to claim 1, wherein: in the second step, the process of the autocorrelation process is:

Shifting the received signal;

Multiplying the shifted received signal by the received signal before shifting, and at a preset width The window is summed; the window is slid from the beginning end to the preset range, and the window corresponding to the different sliding positions is obtained, that is, the autocorrelation result of the received signal. The general method for implementing the wireless communication test platform for transmitting and receiving synchronization according to claim 1, wherein: the general method for implementing the wireless communication test platform for transmitting and receiving synchronization further comprises:: according to the initial phase of the data is 0, Phase correction is performed on the initial phase deviation of the relevant peak position. The general method for implementing the wireless communication test platform for transmitting and receiving synchronization according to claim 1, wherein: the general method for implementing the wireless communication test platform for transmitting and receiving synchronization further comprises:: according to the initial phase of the data being 0, the mutual Phase correction is performed on the initial phase deviation of the relevant peak position.