JPH118584A - Synchronism establishing method for digital mobile communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten time from a call connection to communication start and to improve efficiency in the utilization of a radio line by directly performing audio or data communication, while controlling communication channel transmission slot timing with the latest phase difference notified to a mobile station at the time of a call connection procedure. SOLUTION: When communicating with a certain mobile station 2-1 inside a relevant radio zone, a radio base station 1 receives an up control channel signal transmitted by the mobile station 2-1 through the call connection procedure, compares the reference timing of the radio base station 1 with the timing of a received radio slot, calculates the reception phase difference, adds a mobile station transmission timing controlled variable to the next down control channel and reports it to the mobile station. The mobile station 2-1 controls the transmission timing with the latest notified transmission timing controlled variable every time and transmits the up control channel. After the call connection procedure has been finished, the radio channel is moved to the communication channel so that audio or data communication can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for establishing synchronization between a radio base station and a mobile station, and more particularly to a method for establishing synchronization in a digital mobile communication system.

[0002]

2. Description of the Related Art Digital car telephone systems (RC)
In order to perform voice communication or data communication in RSTD-27), as shown in FIG. 4, a call is made between a radio base station and a mobile station of a communication partner in a corresponding radio zone using a physical communication channel for control. After the connection is established and the connection is completed, the control physical channel is shifted to the communication physical channel, four types of synchronization bursts SB1, SB2, SB3 and SB4 are transmitted and received, and synchronization of the communication physical channel is established. Only when synchronization is successfully established, voice or data communication is started. Further, when an out-of-synchronization is detected during communication, synchronization must be established again by transmitting and receiving a synchronization burst.

[0003]

However, in the conventional synchronization system of a mobile communication system, between the radio base station and the mobile station, when performing voice or data communication on a communication physical channel, each time. Since the communication channel must be synchronized rather than sending and receiving a synchronization burst,
There is a problem that it takes time from the call connection to the start of communication, and the utilization rate of the radio slot is reduced.

[0004] It is an object of the present invention to provide a method of establishing synchronization that improves the efficiency of wireless line utilization by shortening the time from call connection to starting communication without transmitting and receiving a synchronization burst.

[0005]

SUMMARY OF THE INVENTION The present invention mainly relates to a method for establishing synchronization in a mobile communication system comprising a radio base station and a plurality of mobile stations communicating with the radio base station in radio slots. A wireless slot transmitted from a mobile station in a call connection procedure for connecting a wireless line, having a control physical channel for connecting and disconnecting the line and a communication physical channel for transmitting and receiving voice or data. Measures the phase difference between the timing and the radio base station reference timing, notifies the corresponding mobile station of the phase difference at the time of the next downlink radio slot transmission, and the mobile station adjusts the transmission slot timing based on the notified phase difference. After completing the call connection procedure,
Switching to the communication physical channel, the mobile station performs voice or data communication directly while adjusting the communication channel transmission slot timing using the latest phase difference notified during the call connection procedure.

A synchronization method for a mobile communication system according to the present invention comprises:
After completing the call connection, the mobile terminal shifts directly to the communication channel and starts communication. For this reason, it is possible to shorten the time for starting communication and improve the efficiency of use of the wireless line.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a mobile communication system to which the synchronization establishing method of the present invention is applied. The mobile communication system illustrated in FIG. 1 includes a base station 1 and a plurality of mobile stations 2-1, 2-2, and ‥‥‥ 2-n in a wireless zone of the base station.

When communicating with a certain mobile station 2-1 in a corresponding radio zone, the radio base station 1 receives an uplink control channel signal transmitted by the mobile station 2-1 in a call connection procedure, and The mobile station compares the reference timing of the base station 1 with the timing of the received radio slot, calculates the reception phase difference, adds the mobile station transmission timing adjustment amount to the next downlink control channel, and notifies the mobile station.

The mobile station 2-1 adjusts the transmission timing with the notified latest transmission timing adjustment amount each time,
After transmitting the uplink control channel, after the call connection procedure is completed, the radio channel is shifted to the communication channel, voice or data communication is performed. The uplink transmission timing is adjusted by the timing adjustment amount notified by the station 1.

Next, the operation of the embodiment of the present invention will be described in detail with reference to the drawings. FIG. 2 is a sequence diagram from a call connection to the start of communication on a communication channel, and FIG. 3 is a diagram showing a format of a communication wireless channel.

As shown in FIG. 2, when performing communication, the mobile station first transmits a "call setup" message to the base station using a control physical channel.

When the base station receives the control channel message transmitted by the mobile station, the base station measures the reception phase difference between the received signal and the reference reception timing, and based on the measured reception phase difference, The next transmission timing adjustment amount is calculated, and the “call setting acceptance” message and the mobile station next transmission timing adjustment amount are transmitted on the control physical channel, and the “authentication request” message is also transmitted on the control physical channel. And the mobile station next transmission timing adjustment amount.

The mobile station adjusts the transmission timing of the “authentication response” signal message transmitted on the next control channel based on the received next transmission timing adjustment amount, and transmits the message to the base station.

[0015] After receiving the "authentication response" message transmitted by the mobile station, the base station newly measures the reception timing phase difference, calculates the next transmission timing adjustment amount of the mobile station, and uses the control channel for control. The "radio channel designation" message and the mobile station next transmission timing adjustment amount are transmitted.

When the mobile station receives the "radio channel designation" message and the next transmission timing adjustment amount, the mobile station switches the radio channel to the designated communication channel, and transmits the voice or data with the designated next transmission timing adjustment amount. Transmit the signal to the base station and start communication.

During communication on the communication channel, the base station
Each time an uplink communication channel transmitted by the mobile station is received, the phase difference of the reception channel is measured. If the measured phase difference of the reception channel is larger than a specified value, the communication channel pre-synchronization format shown in FIG. 3 is designated. If the measured phase difference of the reception channel is smaller than the specified value, the communication channel synchronization format shown in FIG. 3 is designated, the mobile station next transmission timing adjustment amount is calculated, and the mobile station next transmission timing adjustment amount is added to the downlink communication channel. Send to the station.

A mobile station always transmits a voice or data signal with a transmission timing adjustment amount specified by the base station and a communication channel transmission format.

[0019]

As described above, according to the present invention, there is no need to transmit and receive a synchronous burst after a call connection, so that it is possible to improve the use efficiency of a radio channel. As a result, when communication is performed using the same communication time and the same amount of data, the occupation time of the wireless line can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a mobile communication system.

FIG. 2 is a sequence diagram from a call connection to the start of communication on a communication channel.

FIG. 3 is a diagram showing a format of a communication channel.

FIG. 4 is a sequence diagram of synchronization establishment of a communication channel according to the related art.

[Explanation of symbols]

 1 base station 2-1 to 2-n mobile station

Claims (3)

[Claims] In a method for establishing synchronization of a mobile communication system comprising a radio base station and a plurality of mobile stations communicating with the radio base station in radio slots, control for mainly connecting and disconnecting a radio communication line is provided. And a communication physical channel for transmitting and receiving voice or data, and in a call connection procedure for connecting a radio line, a radio slot timing and a radio base station reference timing transmitted from a mobile station. When the next downlink radio slot is transmitted, the corresponding mobile station is notified of the phase difference, and the mobile station adjusts the transmission slot timing based on the notified phase difference. The mobile station switches to the communication physical channel, and the mobile station adjusts the communication channel transmission slot timing directly using the latest phase difference notified during the call connection procedure. Other synchronization establishing method, which comprises carrying out the data communication. 2. The method for establishing synchronization according to claim 1, wherein the communication physical channel has two types of transmission signal formats, and when a phase difference notified from a radio base station is larger than a specified value, a predetermined value is set. Send in sync signal format,
A synchronization establishing method, characterized in that when a phase difference notified from a radio base station is smaller than a specified value, transmission is performed in a synchronization signal format. 3. The synchronization establishing method according to claim 1, wherein the radio base station receives the uplink communication channel each time it receives an uplink communication channel transmitted from a mobile station during communication on a communication physical channel. A method for establishing synchronization, comprising measuring a phase difference and transmitting the same to a mobile station.