JPH0974586A - Radio synchronizing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quicken synchronization with a remote base station by detecting an information channel in addition to the detection of a control channel and adjusting a clock from these detection results. SOLUTION: A control channel(CCH) detection part 13 searches for the CCH of a base station at an interval of 100ms from the detected timing. When the CCH is detected, the clock of the base station and the clock of its own base station are synchronized by recording the receiving timing of the CCH by a 100ms timing measuring part 14, calculating a reception interval and adjusting the interval in a clock adjusting part 17. After the remote base station RBS synchronization by the CCH is established, an information channel (TCH) detection part 15 receives timing information from the 100ms timing measuring part 14. The TCH detection part 15 searches for the synchronizing burst or the TCH burst of the base station at an interval of 5ms from the detected timing and adjusts the clock from the detected results of the CCH and TCH.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio synchronizing apparatus used in a radio telephone for digital telephone communication such as PHS next generation cordless telephone (PHS).

[0002]

2. Description of the Related Art Each base station of a digital radio telephone such as a PHS is connected to a digital line such as an ISDN line. Normally, each base station synchronizes with the ISDN line and performs operations between the base stations and other operations. It is supposed to do. For this reason, when the clocks of the ISDN lines of the base stations are not synchronized or the base stations not connected to the ISDN line are not synchronized with each other, communication between the base stations should be performed. I can't.

Therefore, in order to synchronize these base stations, the base station which is the synchronization source of the clock is determined, and the other base stations receive the radio wave of the synchronization source base station and synchronize with the remote base station (hereinafter referred to as "synchronization"). , RBS synchronization).

FIG. 3 shows the configuration of a conventional radio synchronizer for performing RBS synchronization. In FIG. 3, reference numeral 21 is a demodulator for demodulating a radio signal, 22 is a receiving buffer, and 23 is a control channel (hereinafter CC) transmitted from a mobile station by radio.
CCH detection unit for detecting H), 24 is a CCH detection unit 23
Represents a clock timing measuring unit that measures the timing when the control channel is received, and 25 represents a clock adjusting unit that adjusts the clock period.

The operation of the radio synchronizer configured as described above will be described below. When performing RBS synchronization, the own base station detects a CS-ID (base station personal identification number) radio signal from a surrounding base station and transmits the information having the strongest received electric field strength among the detected information. The base station to be synchronized is determined by a method such as synchronizing with the base station or being notified of the CS-ID of the base station to be synchronized from the management center or the like.

The CCH detector 23 searches for the CS-ID of the remote base station determined from the received burst signals received by the demodulator 21. When the information about the CCH (control channel) of the remote base station is detected, the CCH detection unit 23
Is the CCH transmission interval (PHS
Then, the CCH search of the remote base station is performed at 100 ms intervals.

Each base station records the reception timing of CCH in the clock timing measuring section 24, calculates the reception interval, and adjusts it in the clock adjusting section 25 to synchronize the clock of the remote base station with the clock of its own base station. .

[0008]

However, in the above-described conventional configuration, each base station has a CCH (control channel) for transmitting control information of the TCH (information channel) for the clock synchronization source to originally perform voice communication or data transmission. ), The RBS synchronization is performed by transmitting information for synchronization and actually synchronizing with the CCH. This CCH is an auxiliary channel of TCH, and its cycle is longer than that of TCH (while TCH has a cycle of about 5 ms, CCH has 1 cycle).
(00 ms cycle).

For this reason, if a radio failure occurs at a certain point and the CCH is not received once, the next reception cannot be performed until 100 ms later. Moreover, several cycles of clocks are required for synchronization. For this reason, if the synchronization is lost due to noise or the like, and if the synchronization is to be re-established, the synchronization may be lost for a long time of several 100 ms, and there is a problem that communication cannot be performed during that time.

In view of the above conventional problems, it is an object of the present invention to provide a radio synchronizer capable of quickly performing RBS synchronization.

[0011]

In order to achieve the above-mentioned conventional problems, the present invention detects TCH in addition to detecting CCH, and adjusts the clock based on the detection results of CCH and TCH.

[0012]

According to the present invention, with the above-described structure, information is actually transmitted, and the clock is adjusted using the information of the TCH having a short cycle, so that synchronization can be performed in a short time.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic configuration diagram of a wireless synchronizing apparatus in an embodiment of the present invention.

In FIG. 1, reference numeral 11 is a demodulator for demodulating a radio signal, 12 is a receiving buffer, and 13 is a CCH detector, which are not different from the conventional ones and will not be described.

Reference numeral 14 denotes a 100 ms timing measuring unit, which is the same as the conventional clock timing measuring unit 24. Further, 15 is a TCH detecting section for detecting the information of the call channel, 16 is a timing for measuring the timing when the TCH detecting section 23 receives the information of the call channel 5 m
The s-timing measuring unit 17 is a clock adjusting unit, which is the same as the conventional one, and therefore its explanation is omitted.

The operation of the wireless synchronizing apparatus configured as described above will be described below with reference to the flowchart of FIG.

When RBS synchronization is performed, first, CCH synchronization is performed as in the conventional case. That is, the own base station detects CS-ID information having a strong received electric field strength from surrounding base stations, or the CS of the base station synchronized from the management center or the like.
-Determine the base station to be synchronized by being notified of the ID (step 1).

The CCH detection unit 13 searches the received burst for the CS-ID of the determined base station (steps 2 to 4).

From the CCH, the CS-ID of the target base station
Is detected, it is recorded by the timing measuring unit 14 for 100 ms, and the CCH detecting unit 13 detects 10
The CCH of the base station is searched at 0 ms intervals (step 5). When the next CCH is detected, the CCH reception timing is set to 1
The timing is recorded by the 00 ms timing measuring unit 14, the reception interval is calculated, and the clock adjusting unit 17 adjusts the clock to synchronize the clock of the base station with the clock of the own base station (step 6).

After RBS synchronization by CCH is established, T
The CH detection unit 15 receives the timing information from the 100 ms timing measurement unit 14, monitors the transmission slots other than the CCH transmission slot of the remote base station that are not used by the base station for transmission and reception, and searches for a synchronization burst ( Step 7). If the synchronization burst cannot be detected, the carrier number is changed and the monitoring is repeated (step 8). When a synchronization burst having a CS-ID that matches the CS-ID of the base station is detected (step 9), the TCH detection unit 15 searches for a synchronization burst or TCH burst of the base station at 5 ms intervals from the detected timing ( Step 10).

In the case of digital communication, the TCH control information and identification information are all transmitted on the CCH.
Has no CS-ID, and a TCH alone cannot distinguish a TCH of a remote base station from a TCH of another base station. Therefore, the synchronization burst of the base station having the CS-ID is detected, and subsequently the TCH detected in the same transmission slot is used as the TCH of the remote base station for synchronization.

This synchronization operation is a synchronization burst or TCH.
Is detected, the clock timing of the own base station at the time of detection by the 5 ms timing measuring unit 16 is measured, the clock timing interval is calculated, the clock adjustment unit 17 calculates the clock deviation with respect to the remote base station, and the measurement by CCH If there is a difference between the result and the measurement result by TCH,
This is performed by giving priority to the synchronization by CCH (step 11).

When TCH transmission of the own base station is started in the same slot during TCH synchronization, TCH synchronization is interrupted.

[0024]

INDUSTRIAL APPLICABILITY According to the present invention, in addition to CCH detection, TCH
Is detected and the clock is adjusted from the detection results of CCH and TCH, so information is actually transmitted, and it becomes possible to investigate the clock by using the information of TCH with a short cycle. Since synchronization is possible in a short time, resynchronization can be performed in a short time even if a radio failure occurs and the synchronization is lost, and communication is not lost for a long time.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a wireless synchronization device according to an embodiment of the present invention.

FIG. 2 is an operation flowchart of a wireless synchronization device according to an embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a conventional wireless synchronization device.

[Explanation of symbols]

 11 demodulator 12 reception buffer 13 CCH detection unit 14 100ms timing measurement unit 15 TCH detection unit 16 5ms timing measurement unit 17 clock adjustment unit

Claims (1)

[Claims] 1. A demodulator for demodulating a signal from a reference base station, a first detector for detecting an information channel for transmitting information from the signal demodulated by the demodulator, and the demodulator. A second detector that detects control information of the information channel from the signal demodulated by the above; and a clock adjuster that adjusts the synchronous clock. The first detector and the second detector are A wireless synchronization device, characterized in that the clock adjustment unit is adjusted based on a detection result.