JP2008245228A - Radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication system capable of communicating with a mobile station facility located outside a cover area of a base station or in a dead zone, and reducing entire costs. <P>SOLUTION: An in-vehicle radio device 3 comprises an in-vehicle radio device body 3a and a handset 3b. The handset 3b is removably connected to the in-vehicle radio device body 3a by an extending/contracting cable 3c. Furthermore, the handset 3b is operated singly as a portable radio device and comprises components such as a display screen 31, input keys 32, non-illustrated microphone and speaker required for functioning as a portable radio device. When the handset 3b is removed, the in-vehicle radio device 3 operates as a portable radio device 30 and the in-vehicle radio device body 3a is switched as a relay radio device 32. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a radio communication system, and more particularly to a radio communication system that enables radio communication outside a base station call area or in a dead zone where radio waves are difficult to reach in digital mobile radio communication constructed as a self-supporting communication network. .

2. Description of the Related Art Conventionally, a digital wireless communication system that performs communication between a base station and a mobile station or between mobile stations is known as a digital mobile communication system constructed as a self-supporting communication network. As an example of this, FIG. 6 shows TDMA (Time Division Multiple
1 shows an outline of an access) type mobile communication system. The communication system is a two-wave duplex system with an upstream frequency f1 and a downstream frequency F1.

  When the in-vehicle wireless device 2 and the portable wireless device 7 make a call, the radio wave from the in-vehicle wireless device 2 is transmitted at f1, and the base station 1 converts the signal into the frequency of F1 and sends it to the portable wireless device 7. . The portable wireless device 7 also transmits at f1 and is received by the base station 1, converts the signal to the frequency of F1, and sends it to the in-vehicle wireless device 2.

  Such communication can be easily performed within the base station call area 10, but communication is difficult outside the base station call area 10 (area where the radio waves of the base station 1 do not reach).

  In such a case, for example, by installing the portable repeater 5 in the base station call area 10, communication with the portable wireless device 6 outside the base station call area 10 becomes possible.

  That is, the radio wave from the in-vehicle wireless device 2 is transmitted at the frequency f1 and is transmitted via the base station 1 at the frequency F1. The portable repeater 5 receives this signal and sends it to the portable wireless device 6 at the frequency F2. The portable wireless device 6 outside the base station call area 10 receives this radio wave and performs communication. The portable wireless device 6 transmits the radio wave of f2 and receives it by the portable repeater 5. The portable repeater 5 transmits a signal at the frequency f1, and is received by the in-vehicle wireless device 2 via the base station 1 at the frequency F1. By adopting such a method, a call with a mobile station radio outside the base station call area 10 becomes possible.

  Further, in Patent Document 1, even when each mobile radio communication terminal device is placed in a position where a call cannot be made, relay is performed by causing the mobile radio communication terminal device of another station located in the vicinity to perform a relay process. Mobile radio communication systems that can do this have been proposed.

JP 2003-318799 A

However, in the conventional example in which the above-described portable repeater is installed, it is necessary to always prepare a portable repeater, and many portable types can be used in accordance with in-vehicle wireless devices or portable wireless devices moving in unspecified areas. There is a problem that it is necessary to prepare a repeater.
Further, in Patent Document 1, since a mobile radio communication terminal device that has undertaken relay processing cannot communicate with itself by providing relay processing to another station, a plurality of transmission / receptions are made to the nuclear mobile communication terminal device. There is a problem that it is necessary to provide a circuit and the cost is high.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a radio communication system capable of communicating with mobile station equipment outside the coverage area of a base station or in an insensitive area and reducing the overall cost. is there.

In order to solve the above problems, a wireless communication system according to the present invention includes a mobile station facility located in a base station call area and a mobile station facility outside the base station call area, or a base station facility and the mobile station facility. In a wireless communication system in which communication with a mobile station facility outside the base station call area is performed via a repeater facility within the base station call area, a part of the mobile station facility can be switched as a repeater facility The mobile station equipment in the base station call area is switched and used as a repeater equipment.
By configuring in this way, by switching a part of the mobile station equipment in the base station call area as a repeater equipment, the mobile station equipment in the base station call area and the mobile station placed outside the base station call area Communication between the equipment or between the base station equipment and the mobile station equipment located outside the base station call area can be performed via the repeater equipment.

  According to the present invention, it is possible to configure a wireless communication system with a minimum equipment investment when communication with mobile station equipment located outside the base station call area is required.

The present embodiment will be described with reference to FIGS.
First, a switchable in-vehicle wireless device according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 shows an in-vehicle radio (relay radio (relay equipment)) 3 which is a mobile station equipment used in the present embodiment.
As shown in FIG. 1A, the in-vehicle wireless device 3 includes an in-vehicle wireless device main body 3a and a handset 3b. The handset 3b is detachably connected to the in-vehicle wireless device main body 3a with an extendable cable 3c. The handset 3b alone operates as a portable radio device (mobile station equipment) 4 and includes components necessary for functioning as a portable radio device, such as a display screen 31, an input key 32, a microphone and a speaker (not shown). Yes. When the in-vehicle wireless device 3 is detached, the in-vehicle wireless device 3 operates as a portable wireless device 30 as shown in FIG. 1B, and the in-vehicle wireless device main body 3 a that is a part of the in-vehicle wireless device 3 serves as the relay wireless device 32. Switch.

  Next, a block diagram of the in-vehicle wireless device 3 configured as described above is shown in FIG.

When the handset 3b of the in-vehicle wireless device 3 is detached from the in-vehicle wireless device main body 3a, it becomes a portable wireless device 30 (FIG. 3). When used with the handset 3b, the hatching in FIG. The part is stopped. When used as the in-vehicle wireless device 3, the wireless unit of the in-vehicle wireless device main body 3a operates.
The in-vehicle wireless device main body 3 a controls the entire control and modulation / demodulation at a portion having the baseband processing unit 50 and the control unit 51. The signal processed by the baseband processing unit 50 passes through a D / A converter (D / A) 52, is modulated by a modulator (MOD) 53, and an unnecessary portion is bandpass filtered through a mixer (MIX) 54. The power is removed by (BPF) 55 and amplified to a desired power by power amplification unit (AMP) 56. During reception, the signal input from the antenna 57 passes through the duplexer (DUP) 58, and unnecessary components are removed by the band pass filter (BPF) 59, and the intermediate frequency band is obtained by the amplifier (AMP) 60 and the mixer (MIX) 61. After being converted, the digital signal is converted by an A / D converter (A / D) 63 via a band pass filter (BPF) 62. In the baseband processing unit 50, processing such as a voice codec is performed, and a voice call or the like becomes possible. At this time, the transmission frequency is, for example, f1, and the reception frequency is F1.
The in-vehicle wireless device 30 includes a baseband processing unit 70, a control unit 71, a D / A converter (D / A) 72, a modulator (MOD) 73, a mixer (MIX) 74, and a bandpass filter (BPF) 75. , Power amplifier (AMP) 76, antenna 77, sync word (SW) 78, band pass filter (BPF) 79, amplifier (AMP) 80, mixer (MIX) 81, band pass filter (BPF) 82, A / D It is composed of a converter (A / D) 83.
The operation of the wireless communication system according to the present invention using the in-vehicle wireless device 3 configured as described above as the relay wireless device 32 will be described with reference to FIGS. 4 and 5.
As shown in FIG. 4, when the portable wireless device 4 is outside the base station call area 10, the in-vehicle wireless device 3 performs a switching operation as the relay wireless device 32 by removing its own handset 3 b. A radio wave from the in-vehicle wireless device (mobile station equipment) 2 is transmitted by f1, and is transmitted by a radio wave F1 through the base station 1 which is a base station equipment. The in-vehicle wireless device 3 (relay wireless device 32) receives this signal and sends it to the portable wireless device 4 at the frequency of F2, and the portable wireless device 4 receives this radio wave and performs communication.
On the other hand, at this time, the portable wireless device 4 transmits a radio wave at f2 and receives it by the in-vehicle wireless device 3 (relay wireless device 32). Next, the in-vehicle wireless device 3 (relay wireless device 32) transmits a signal at a frequency of f1, and the in-vehicle wireless device 2 receives the signal at a frequency of F1 via the base station 1.
Thus, when the handset 3b is removed from the in-vehicle wireless device 3 and the in-vehicle wireless device main body 31 is used as the relay wireless device 32, the handset 3b can operate as the portable wireless device 30 and is outside the base station call area 10 (for example, It can be used indoors.
That is, as shown in FIGS. 4 and 5, when the in-vehicle wireless device main body 3a operates as the relay wireless device 32 and receives the radio frequency F1 from the base station 1, it converts the frequency to F2 and transmits it. Similarly, when receiving from the portable radio device 30 at the frequency f2, a radio signal is transmitted at the frequency of f1.
According to the radio communication system of the present embodiment configured as described above, the in-vehicle radio device 3 placed in the base station call area 10 is used as the relay radio device 32, so that the base station call area 10 Communication between the in-vehicle wireless device 2 placed and the portable wireless device 4 placed outside the base station call area 10 can be performed via the relay wireless device 32.
Therefore, in the present embodiment, when communication with mobile station equipment such as the portable wireless device 4 placed outside the base station call area 10 is required, a wireless communication system can be configured with minimum equipment investment. .

It is explanatory drawing which shows the switchable vehicle-mounted radio | wireless machine used with the radio | wireless communications system of this invention. It is a block diagram which shows the circuit structure in the case of using the mobile station equipment which concerns on embodiment of this invention as a vehicle-mounted radio. It is a block diagram which shows the circuit structure in the case of using the vehicle-mounted radio | wireless apparatus which concerns on embodiment of this invention as a relay radio | wireless machine and a portable radio | wireless machine. 1 is an overall view showing a wireless communication system according to an embodiment of the present invention. It is a figure which shows the transmission / reception timing of the relay radio | wireless machine in embodiment of said radio | wireless communications system. It is a general view which shows the radio | wireless communications system by a prior art.

Explanation of symbols

1: base station, 2: in-vehicle radio, 3: in-vehicle radio (relay radio), 3a: in-vehicle radio body, 3b: handset, 4: portable radio, 10: base station call area

Claims (1)

Communication between mobile station equipment in a base station call area and mobile station equipment outside the base station call area, or communication between a base station equipment and mobile station equipment outside the base station call area In a wireless communication system to be performed via a repeater facility in
A part of said mobile station equipment has a structure that can be switched as repeater equipment, and the mobile station equipment in said base station call area is switched and used as repeater equipment.

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