JPH09238119A - Radio repeater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely establish synchronization when a communication control signal transmitted from a base station in a 100-ms cycle is transmitted to a mobile station from a radio repeater in a 150-ms cycle. SOLUTION: During the waiting time of a mobile station C, the synchronization establishing and correcting section of a repeater B synchronizes the mobile station C to a base station A by generating a timing signal at regular time intervals of 300ms which is the least common multiple of 100ms and 150ms. When the mobile station C shifts to a calling state from the waiting state, the synchronization establishing and correcting section synchronizes the station C to the base station A by generating a timing signal for synchronizing a call control signal transmitted from the base station A in a 5-ms cycle in the same 5-ms cycle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless relay device for relaying wireless communication between a base station and a mobile station using a TDMA / TDD method for performing communication by time division multiple access and time division bidirectional transmission. .

[0002]

2. Description of the Related Art Time division multiple access TDMA (Time Divisio)
n Multiple Access) is a method in which a radio frequency is time-divided, a specific time zone is assigned to a user, and communication is performed in the assigned time zone.
The (Time Division Duplex) is to use the same radio frequency by time division for transmission and reception, and when accommodating a plurality of mobile stations, a plurality of channels are used. FIG. 3 shows a configuration in which there are three mobile stations, and the public base station 21 can be simultaneously connected to three mobile stations 31, 32, 33. The mobile station 31 transmits and receives in the slot # 1 designated by the public base station 21. When the mobile station 31 receives the radio wave transmitted by the public base station 21 in the slot # 1, it transmits the radio wave to the public base station 21 in the slot # 1 in synchronization with the reception timing of the public base station 21. Similarly, the other mobile stations 32 and 33 also perform transmission / reception in synchronization with the transmission / reception timing of the public base station 21 using the slots # 3 and # 4, respectively. In this case, slots # 1, #
3 and # 4 are used for the call channel, slot #
2 is used for the control channel and each mobile station 31,
32 and 33 receive the control notification information (LCCH) intermittently transmitted from the base station 21 during standby.

[0003]

In the conventional mobile communication described above, radio waves may not reach sufficiently when the distance between the base station and the mobile station is large, so that the radio wave may not reach between the base station and the mobile station. A method has been proposed in which a wireless relay device called a home antenna (hereinafter, also simply referred to as a relay) is arranged to smoothly perform wireless communication connection. The problem here is that the repeater must be synchronized to both the base station and the mobile station, and when waiting for the mobile station, the repeater
It is stipulated that a communication control signal (LCCH) which is intermittently transmitted in 100 ms from a base station using a control channel is received and transmitted to a mobile station at a constant cycle longer than that. Therefore, there arises a problem of how to synchronize a fixed cycle of 100 ms output from the base station with a fixed cycle longer than that output from the repeater and to correct the same.

The present invention solves such a conventional problem by using a TDMA / TDD system for performing communication by time division multiple access and time division bidirectional transmission, and between a base station and a mobile station. In a wireless relay device that relays wireless communication, when the communication control information is transmitted to the mobile station when the mobile station is on standby, even if a cycle different from that of the base station is used, the synchronization between the base station and the mobile station is ensured. It is an object of the present invention to provide a wireless relay device that can do the above.

[0005]

In order to achieve the above-mentioned object, the present invention comprises means for synchronously correcting for each time interval of the least common multiple of a fixed cycle in a base station and a fixed cycle in a wireless relay device. As a result, the base station and the mobile station can be reliably synchronized.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention uses a TDMA / TDD system for performing communication by time division multiple access and time division bidirectional transmission, and uses a radio between a base station and a mobile station. In a wireless relay device that relays communication, when the mobile station is in a standby state, the wireless relay device receives a communication control signal transmitted from the base station at a fixed cycle and moves at a fixed cycle longer than the fixed cycle of the base station. When transmitting to a station, the wireless relay device is provided with means for synchronously correcting at a time interval of the least common multiple of a fixed period in the base station and a fixed period in the wireless relay device, and a period different from that of the base station is used. However, it is possible to ensure synchronization between the base station and the mobile station.

According to a second aspect of the present invention, in the wireless relay device according to the first aspect, when the mobile station shifts from the standby state to the talking state, the wireless relay device is transmitted from the base station at a constant cycle. When a call control signal is received and transmitted to the mobile station at the same fixed cycle, the means for synchronously correcting the fixed cycle is provided. It is possible to reliably achieve synchronization in.

(Embodiment) FIG. 1 shows a schematic configuration of a radio relay apparatus, that is, a relay according to an embodiment of the present invention. In FIG. 1, A is a base station which transmits a communication control signal in a cycle of 100 ms and a call control signal in a cycle of 5 ms, and B receives a communication control signal of a cycle of 100 ms from base station A and transmits it in a cycle of 150 ms. A repeater that transmits to the mobile station C, and C is a mobile station that receives a communication control signal from the repeater B at a cycle of 150 ms. In the repeater B, 1 is a power supply unit, 2 is a CPU, 3 is a base station signal processing unit,
Reference numeral 4 is a synchronization establishment / correction unit, 5 is a mobile station signal processing unit, 6 is a radio unit having a PLL circuit as a synchronization means, and 7 is a transmitting / receiving antenna.

Next, the operation of the above embodiment will be described with reference to the timing chart of FIG. FIG.
In (a), when the mobile station C is on standby, the repeater B receives the communication control signal intermittently transmitted from the base station A in 100 ms at the antenna 7, and the repeater B receives the preamble and unique word in the communication control signal. And recognize that it is a communication control signal. When the relay station B transmits this communication control signal to the mobile station C, synchronization establishment /
The correction unit 4 receives the synchronization establishment request from the CPU 2, detects the interrupt signal generated by the mobile station signal processing unit 5 immediately after that, generates a timing signal synchronized with this, and generates this timing signal. Tell to. This timing signal is 100 m, which is the cycle of the communication control signal output by the base station A.
s and the repeater B must output the communication control signal to the mobile station C at a cycle of either 150 ms, but the circuit configuration in the synchronization establishment / correction unit 4 becomes complicated every 100 ms. Also, it cannot be used because synchronization may be lost every 150 ms. Therefore, the synchronization establishment / correction unit 4 uses the least common multiple of 300 m
It is output to the base station signal processing unit 3 as a synchronization correction signal every s cycles. If the cycle is 300 ms, base station A and mobile station C
Since the variation of the clock cycle between them is set to ± 3ppm, the maximum is 6ppm, which is 300ms.
The period is 1.8 μs. This is appropriate as the cycle of the synchronization correction signal because the information amount is within 1 symbol (about 2.6 μs). As a result, the base station signal processing unit 3
Is in agreement with the synchronization of the mobile station signal processing unit 5, and it becomes possible to establish and correct synchronization between the base station A and the mobile station C via the repeater B.

In this way, after the synchronization at the time of waiting for the mobile station C is established, the call is issued by a call request from the mobile station C side using the control channel or by an incoming call notification from the base station A. Once connected and switched to the call channel, first to establish synchronization in the call channel,
As shown in FIG. 2B, since the call control signal is sent from the base station A at the same 5 ms cycle as the cycle of the call signal,
In the repeater B, the wireless unit 6 demodulates the call control signal and transmits it to the synchronization establishment / correction unit 4. The synchronization establishment / correction unit 4 generates a timing signal having the same cycle as the 5 ms cycle from the base station A, and sends this to the mobile station signal processing unit 5. In response to this, the mobile station signal processing unit 5 transmits a call control signal to the mobile station C at a cycle of 5 ms. As a result, synchronization can be established and corrected between the base station A and the mobile station C via the repeater B even during a call.

As described above, in the above-described embodiment, when the mobile station C is on standby, the repeater B receives the communication control signal transmitted from the base station A at a cycle of 100 ms, and sets it to 1
When transmitting to the mobile station C at a cycle of 50 ms, the synchronization establishment / correction unit 4 generates a timing signal so as to perform synchronous correction at every 300 ms, which is the least common multiple of 100 ms and 150 ms, so that it is longer than the base station A. Even when the cycle is used, the base station A and the mobile station C can be reliably synchronized. Also, when the mobile station C shifts from the standby mode to the call mode, the repeater B receives the call control signal transmitted from the base station A in a 5 ms cycle, and transmits the same signal for 5 m.
When transmitting to the mobile station C in the s cycle, the synchronization establishment / correction unit 4
However, since the timing signal is generated so as to perform synchronous correction every 5 ms cycle, even in the call state of the mobile station C,
The base station A and the mobile station C can be reliably synchronized.

[0012]

As described above, the wireless relay device according to the present invention, when transmitting communication control information to a mobile station when the mobile station is on standby, uses a fixed period in the base station even if a cycle different from that of the base station is used. Since the means for correcting the synchronization is provided for each time interval of the least common multiple of the cycle and the fixed cycle in the wireless relay device, the base station and the mobile station can be reliably synchronized.

[Brief description of drawings]

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

FIG. 2A is a timing diagram of communication control signals when the mobile station of the same device is on standby; and FIG. 2B is a timing diagram of call control signals when the mobile station of the same device is in standby mode and in a call mode.

FIG. 3 is a schematic diagram showing a conventional TDMA / TDD system.

[Explanation of symbols]

 A base station B repeater C mobile station 1 power supply unit 2 CPU 3 base station signal processing unit 4 synchronization establishment / correction unit 5 mobile station signal processing unit 6 radio unit 7 antenna

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Saori Naito 4-3-1, Tsunashima-higashi, Kohoku-ku, Yokohama-shi, Kanagawa Matsushita Communication Industrial Co., Ltd.

Claims (2)

[Claims] 1. A wireless relay device for relaying wireless communication between a base station and a mobile station using a TDMA / TDD system for performing communication by time division multiple access and time division bidirectional transmission, wherein the mobile station is in a standby state. When the wireless relay device receives a communication control signal transmitted from the base station at a constant period and transmits the communication control signal to the mobile station at a constant period longer than the constant period of the base station, And a fixed period in the wireless relay device, the wireless relay device comprising means for synchronously correcting each time interval of the least common multiple. 2. When the mobile station shifts from the stand-by state to the call state, when the wireless relay device receives the call control signal transmitted from the base station in a constant cycle and transmits it to the mobile station in the same constant cycle, The wireless relay apparatus according to claim 1, further comprising means for synchronously correcting the fixed cycle.