JPH08251654A - Communication synchronization method between multiple stations - Google Patents

Abstract

(57) [Abstract] [Purpose] For example, when switching the other party's communication station to continue wireless communication such as mobile communication, the conventional method takes a short time to newly obtain phase synchronization, and communication is temporarily interrupted. Such phenomenon occurs. The purpose is to solve this. [Structure] A time signal from GNSS is used as a synchronization clock common to a plurality of stations.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication synchronization method between a plurality of stations, for example, a communication synchronization method between a plurality of stations when communication is continued between the stations while moving in mobile communication.

[0002]

2. Description of the Related Art FIG. 1 is an explanatory diagram for explaining an operation of changing a base station in mobile communication. In mobile communication, as shown in FIG. 1, service area 1 of base station 1
When the mobile station 3 that is in communication 0 and moves to the service area 20 of the base station 2, the base station change point 4 switches the communication base station from the base station 1 to the base station 2. Therefore, the mobile station 3 and the base station 2 are the base station change points 4
Therefore, it is necessary to synchronize the phase of the transmission / reception code. Conventionally, the phase synchronization method in such a case includes a method of pulling in the clock of the own station by a synchronization signal sent from the partner station, a method of synchronizing using the transmission data from the partner station, and the like. However, in both cases, synchronization takes a long time, and during that time, a phenomenon occurs in which communication is temporarily interrupted.

3A and 3B are explanatory views for explaining the operation of receiving a synchronization signal and pulling in the clock of the local station. FIG. 3A is a phase waveform of the transmission signal of the other station, and FIG. Points, (c) shows the clock of its own station, and (d) shows its rising point. Detects each bit of the synchronization signal received from the partner station and the rising or falling point of each frame to perform the phase correction operation of the own station's clock (c). Because of the need to pull in completely uncorrelated signals at the beginning, a rough pull-in operation is generally performed first, followed by a precise correction operation. For this reason, the pull-in operation is performed while switching the correction width. In this operation, the signal waveform (b) is detected by the receiver, the waveform (b) is compared with the waveform (d), and the phase difference is detected. This is performed by inserting and removing the pulse of the upper division cycle of the clock (c) so that this phase difference approaches zero. That is, when it is desired to advance the phase of the clock (c), it is performed by inserting an extra pulse in the pulse train having a constant cycle, and when it is desired to delay the phase, the pulse is removed from the pulse train having the constant cycle.

[0004]

In the conventional communication synchronization system between a plurality of stations as described above, since the phases of the transmission codes of the stations are different and there is no correlation, the communication station from the other station changes each time the communication destination station changes. Normal communication cannot be performed until a new synchronization signal is transmitted. In addition, in the system that synchronizes with the data transmitted from the partner station instead of the synchronization signal, due to the nature of data decoding, it takes more time to pull in than the system using a synchronization signal, and it takes several times to pull in. There was a point.

The present invention has been made in order to solve such a problem, and provides a communication synchronization system between a plurality of stations in which communication is not interrupted by eliminating or extremely reducing the time required for pulling in. It is an object.

[0006]

A communication synchronization system between a plurality of stations according to the present invention comprises means for wirelessly receiving a common time signal for each communication station, and a communication synchronization clock is commonly used by this time signal. It is characterized by having done. Specifically, G
The clock for communication synchronization is made common by the time signal synchronized from the world standard time received from NSS (Global Navigation Satellite System).

[0007]

Embodiments of the present invention will be described below with reference to the drawings. According to the present invention, a plurality of stations are provided with a unit for wirelessly receiving a common time signal for each of the communication stations on the basis of a time reference for synchronization, and the communication signal is shared by the time signals. Specifically, GNSS (Global Navigation Satellite)
It uses a time signal synchronized with the universal standard time received from the (ite system). That is, since each station is provided with a GNSS receiver, a clock within an error of 1 μS can be obtained. Therefore, if this clock is commonly used as a synchronization clock for each station, a bit width of 3 μS or more (communication speed 333.3 Kb
If the communication speed is less than or equal to ps, communication can be started immediately between stations without the need for pull-in operation, and the bit width is 3μ.
Even in the case of S or less (communication speed 333.3 Kbps or more), the communication can be started in a very short time by using the synchronous pull-in operation together. For example, PHS (Persona
(Handy-Phone System) has a transmission speed of 384 Kbps, which is close to the above-mentioned communication speed, so that the synchronization pull-in operation only requires fine adjustment and instantaneous synchronization can be achieved.

FIG. 2 is a block diagram showing a configuration example of an apparatus for explaining the present invention. FIG. 2A is a configuration example of a transmitter, 100 is a GNSS receiver, 101 is a transmission clock generation unit, Reference numeral 102 is a data processing unit, 103 is a data modulation unit, 104 is a frequency conversion unit, and 105 is a high frequency amplification unit. 2B is a configuration example of a receiver, in which 200 is a high frequency amplification unit, 201 is a frequency conversion unit, 202 is a data demodulation unit, 203 is a data reproduction unit, 204 is a GNSS receiver, and 205 is a synchronization clock. The generation unit is shown.

At the transmitter, the time signal from the GNSS is G
The GNSS receiver 100 receives the NSS receiver 100.
From this, a time synchronization signal PPS (Pulse For Second) is input to the transmission clock generation unit 101, where the transmission clock is generated and input to the data processing unit 102. on the other hand,
Digitally processed transmission data (eg, digitally encoded data in PHS) is input to the data processing unit 102, the bit and frame phases of this data are aligned with the transmission clock, and the data modulation unit 1 is used as a serial transmission code.
03, and the frequency converter 104 and the high frequency amplifier 1
Sent via 05. The transmission clock is GN
The clock is a clock in which the time difference between the time when the SS receiver 100 receives the data and the time when the data is actually transmitted from the antenna is corrected.

On the other hand, the receiver also has the same GN as the transmitter.
The SS receiver 204 receives the time signal from the GNSS and outputs the time synchronization signal PPS to the synchronization clock generation unit 205.
The synchronization clock generation unit 205 generates a bit synchronization clock and a frame synchronization clock based on the world time, in which the time delay from the radio wave input from the antenna to the generation unit 205 is corrected. And output to the data reproducing unit 203. On the other hand, the radio signal input from the antenna receives the high frequency amplification unit 200 and the frequency conversion unit 201.
After the signal is demodulated by the data demodulation unit 202 to obtain a baseband signal, the data reproduction unit 203 performs reception processing using the clock generated by the synchronization clock generation unit 205 and performs analog processing ( In PHS, it is output after being converted into voice data. Note that, in general, the transmitter shown in FIG. 2A and the receiver shown in FIG. 2B are built in each wireless station, and therefore, GNSS receivers and the like commonly used for transmission and reception are used. Needless to say.

Further, as shown in FIG. 1, the base stations are installed at different points, and the mobile station 3 moves appropriately. Therefore, even when the time signal from the GNSS is used as a common synchronization clock as described above. The data transmission time varies due to the change of the communication distance. Therefore, the configuration is such that this variation in communication distance is corrected. That is, it is known that position information can be obtained from the GNSS in addition to the time signal. Therefore, an arbitrary point common to each communication station is determined on the coordinate, and each communication station is configured to correct the time delay due to the distance from the point on the coordinate to the own station position in advance in the synchronous clock. By doing this, each communication station can receive the electromagnetic waves as well as being located at the common point, can correct the delay of the electromagnetic waves due to the distance between the communication stations, and the communication distance in the communication between the stations. It is possible to correct the phase shift caused by the.

[0012]

As described above, according to the present invention, a synchronization clock common to a plurality of stations is created by a time signal from the GNSS, so that it is not necessary to newly synchronize even when switching a plurality of stations and continuing communication. It is possible to obtain a communication synchronization method between a plurality of stations that can continue communication and that is not interrupted. Further, by using the position information from the GNSS together, it is possible to easily correct the delay of the electromagnetic wave due to the communication distance, and it is possible to more accurately match the synchronization clocks at each station.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a base station change in mobile communication.

FIG. 2 is a block diagram showing a device configuration example of the present invention.

FIG. 3 is a diagram for explaining a pull-in operation.

[Explanation of symbols]

 100 GNSS receiver 101 transmission clock generation unit 102 data processing unit 203 data reproduction unit 204 GNSS receiver 205 synchronization clock generation unit

Claims (4)

[Claims] 1. In a communication synchronization method between a plurality of stations when switching a destination communication station to continue wireless communication, each communication station includes means for wirelessly receiving a common time signal, and communication is performed using this time signal. A communication synchronization method between multiple stations characterized by using a common synchronization clock. 2. A common time signal wirelessly received by each communication station is a GNSS (Global Navigation Satellite).
2. The communication synchronization system between a plurality of stations according to claim 1, wherein the time signal is a time signal which is synchronized with the world standard time received from the System). 3. A GNS is provided to each communication station in order to receive a time signal synchronized with the universal standard time from the GNSS.
The communication synchronization method between a plurality of stations according to claim 2, further comprising an S receiver. 4. Assuming an arbitrary point common to each communication station on the coordinates, each communication station receives the position information of its own station from the GNSS, and arrives by the coordinate distance between the above point and the own station position. A means for correcting the time delay of the incoming radio wave due to the distance in the communication between the communication stations by calculating the time delay of the radio wave and correcting the communication synchronization clocks respectively. Communication synchronization method between multiple stations described in paragraphs 2 and 3.