JPH0923184A - Radio communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily receive a mobile station signal from a base station by automatically stitching a current antenna to an antenna having different directivity and resending a calling message when the base station can not receive a response message. SOLUTION: A control circuit 12 allows a base station to transmit a position registering request, and at the time of receiving a certification request within a prescribed time, transmits a certification response to the base station and waits the reception of position registration acceptance or rejection for a prescribed time. When a response can not be received within the time, the counting of a resending counter is up. When the count of the counter is not over, an antenna switching circuit 7 is controlled, a current 1st antenna 4 is switched to a 2nd antenna 6, a position registering request is resent, and the operation is repeated until the counting is over. Since the current antenna is switched and a registration request is reserat when position registration acceptance or rejection can not be recenved, the base station can be prevented from being disabled from receiving a calling message from a mobile station by the use of an antenna with low directivity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to antenna selection at the time of transmission of a wireless communication device such as a cordless telephone, a cellular car telephone, a mobile telephone, a PHS or a PDC.

[0002]

2. Description of the Related Art As a wireless communication device (mobile station) for communicating with a base station, there are a cordless phone, a cellular car phone, a mobile phone, a PHS, a PDC and the like. In order to confirm that these wireless communication devices are in a communicable state, the wireless communication device transmits a paging message requesting the return of a response message to the base station, and determines whether or not the response message returned from the base station is received. Determine if communication is possible.

[0003]

By the way, since the base station transmission output is generally set higher than the output of the wireless communication device, the wireless communication device can receive data from the base station. The base station may not be able to receive data from the wireless communication device.

On the other hand, in recent years, a so-called microcellular system has been studied in which the cell radius is 100 m to 10 m in order to increase the number of channels in the cellular system, and the density and the number of base stations are enormous in the microcellular system. . For this reason, it is difficult to install a base station antenna by constructing a tall tower, etc., and the antenna should be installed at the same or lower position as the surrounding building, such as on the roof or wall of a high-rise building or on a public telephone box. Therefore, the propagation characteristics are extremely affected by the visibility of the base station, the condition of buildings and roads around the wireless communication device, and the like. In particular, in such a micro cellular system, the above-mentioned reception failure of the base station is likely to occur.

In a portable wireless communication device,
Usually, the antenna is arranged in the wireless communication device assuming that the user is sitting or standing, but when the user uses it in a peculiar state such as a sleeping state or a bent state, the inclination angle of the antenna is In a disadvantageous direction, the base station may not be able to receive data from the wireless communication device.

In such a case, the transmission data may arrive by changing the direction of the antenna of the wireless communication device. However, it is not easy to change the direction of the antenna depending on the usage situation of the user, etc. However, there is a problem that it affects the propagation loss and causes a state in which communication is not possible.

[0007]

The wireless communication device of the present invention has been made in view of the above points, and the first feature is to transmit a call message requesting a return of a response message from a base station via an antenna. In the wireless communication device, a plurality of antennas each having a different directivity, an antenna switching circuit that switches the antennas, and if the response message is not received within a predetermined time, the antennas are switched and the call message is again sent. The second feature is that a plurality of antennas having different directivities, an antenna switching circuit that switches the antennas, and a tilt of the wireless communication device are detected. And a control circuit for switching the antenna based on the tilt detecting means.

[0008]

Since the present invention is configured as described above, it is possible to automatically select an antenna capable of communication from a plurality of antennas having different directivities at the time of transmission.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the drawings, and the RCR STD-27 standard (digital radio telephone system standard of the Radio Wave System Development Center).
Will be explained in accordance with.

The first embodiment is a radio communication apparatus as a mobile station in the cellular system, and its block diagram is shown in FIG.
Shown in (1) and (2) are a transmission unit and a reception unit, respectively, which are connected to a first antenna (4) connected to the first transmission / reception duplexer (3) and a second transmission / reception duplexer (5). Second
Connected to an antenna switching circuit (7) for switching antennas at the time of transmitting the antenna (6) and a TDMA circuit (8) for demultiplexing voice code, control signal, sync signal, and sync signal. Implements basic wireless communication with a base station (not shown). A radio link connection for communicating with a mobile telephone switching center (not shown) is formed through a base station, and an interface with a public telephone communication network is established through the radio link connection. Also, each antenna (4)
(6) is a fan-shaped beam antenna, which is arranged so as to have different directivities. (9) is CODEC
Thus, the circuit for coding / decoding an audio signal also has an error correction function for reducing the influence of fading or the like. Microphones and speakers (10) and (11) are connected to the CODEC (9).

Reference numeral (12) is a control circuit consisting of a 16-bit microprocessor and an ASIC, which includes an antenna switching circuit (7), a display unit (13) for displaying a telephone number, and a buzzer (Buzzer) for ringing when a call arrives. 14), which is connected to a key circuit (15) for inputting a telephone number, and which will be described later with reference to FIG. 3, antenna switching control, processing of telephone line connection including a wireless section, control of wireless circuits such as transmission output control, various types of telephones. Control functions.

The transmission section (1) comprises a π / 4 shift QPSK modulator (16) and a highly efficient linear power amplifier (17). The π / 4 shift QPSK modulator (16) is composed of an RF band quadrature modulator (18) and waveform shaping (19) from the viewpoint of small size and low power consumption. The waveform shaping (1
In 9), the digital signal processing is used because the burst operation, the transmission output control, and the generation of the control voltage of the power amplifier (17) can be performed efficiently and highly accurately, and the LSI can be realized. The receiving unit (2) includes a first reception circuit (20) connected to the first transmission / reception duplexer (3) and a second reception circuit (2) connected to the second transmission / reception duplexer (5).
A diversity receiver composed of 1) and a demodulator (2
2) and a high-speed switching synthesizer (23) as a circuit peculiar to the digital mobile device.

FIG. 2 is a sequence diagram showing a location registration operation procedure in the RCR STD-27 standard. The position registration operation will be described below with reference to FIG. The base station
When the location registration request is received from the mobile station and the location registration is permitted, the mobile station issues an authentication request. Then, the mobile station transmits an authentication response to the authentication request to the base station. If the base station cannot receive this authentication response within a predetermined time, it checks the number of retransmissions and if it is within the predetermined number of times, it retransmits the authentication request and waits for the authentication response from the mobile station. If the signal cannot be received, this sequence ends. If the authentication response from the mobile station can be received within the predetermined number of retransmissions and the authentication confirmation is OK, the location registration acceptance is sent to the mobile station, and if the location registration fails and roaming is not permitted, the location registration is performed. Send a rejection to the mobile station.
In addition, if the mobile station fails to receive the location registration acceptance or the location registration refusal within a predetermined time (for example, 6 seconds) after transmitting the location registration request to the base station, the mobile station determines that the retransmission is within the allowable number of times. In this case (three times in this case), the location registration request is transmitted again to the base station. In this way, when the position registration acceptance or the position registration refusal is not received, the position registration request is repeatedly sent.

FIG. 3 shows a control circuit (1 according to the first embodiment.
It is a flowchart which shows the antenna switching operation of 2).
In advance, a retransmission counter indicating the retransmission of the location registration request is cleared to zero (not shown). The control circuit (12) transmits a location registration request (S1) to the base station, and when an authentication request is received within a predetermined time (Y of S2), transmits an authentication response (S3) to the base station. , And waits for a predetermined time to receive the position registration acceptance or the position registration refusal transmitted from the base station that has received the request (S4, S5, S7). When the position registration acceptance or the position registration refusal can be received (Y in S4 and S5), the retransmission counter is cleared (S6), and this sequence ends. If the location registration acceptance or the location registration refusal cannot be received within the predetermined time (N in S4, S5, Y in S7), the retransmission counter is counted up (S8). Here, when the retransmission count does not exceed (N in S9), if the currently used antenna is the first antenna (Y in S10), the antenna switching circuit (7) is controlled. Switch to the second antenna (S
11), if it is not the first antenna (N in S10), the first
After switching to the antenna (S12), the location registration request (S1) is retransmitted. Repeat this sequence until the retransmission counter runs out (here, 3 times),
When the retransmission counter has exceeded (Y of S10), the retransmission counter is cleared (S4), and this sequence is ended.

As described above, when the position registration acceptance or the position registration refusal is not received, the antenna is changed and the position registration request is sent again. As a result, it is possible to prevent the base station from being unable to receive the call message from the wireless communication device due to the use of the antenna having the poor directivity.

Although there are two types of antennas in the first embodiment, more antennas may be used.

Further, in the first embodiment, when the base station cannot receive the location registration request, it does not send the authentication request. Therefore, when the reception of the authentication request times out, the antenna is switched and the authentication request is made again. , The location registration request was sent. However, even if the base station can receive the location registration request, the authentication request may not be sent depending on the judgment of the base station. Therefore, when the reception of the authentication request is over (Y in S2), the antenna is turned on. The specification may be such that it is ended without switching.

The second embodiment is a portable radio communication device, which will be described with reference to the drawings. FIG. 4 shows a block diagram of the second embodiment, which is a block diagram of the first embodiment.
The tilt detecting means (24) is added to the above. The inclination detecting means (24) is connected to the control circuit (12), detects the inclination of the wireless communication device with respect to the direction of gravity by geomagnetism, gravity, satellites, etc., and outputs the information to the control circuit (12). In the second embodiment, the first antenna (4) is arranged so as to have a directivity assuming that the user is sitting or standing, and the second antenna (6) is arranged when the user is sleeping. Assuming that the antenna is arranged so as to have a directivity orthogonal to that of the first antenna.

When the user sits down and uses the wireless communication device, the control circuit (12) causes the antenna switching circuit (7) to use the first antenna (4) based on the output of the tilt detecting means (24). Control. Further, when the user uses the wireless communication device while sleeping, the control circuit (12) controls the use of the second antenna (6).

In this way, it is possible to prevent transmission / reception failure due to the tilt of the wireless communication device.

[0021]

As described above, according to the present invention, when the response message from the base station cannot be received as described above, the antenna is automatically switched to another antenna having a different directivity and the paging message is transmitted again. It becomes easy for the base station to receive the signal of the communication device.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is a sequence diagram showing a location registration operation procedure.

FIG. 3 is a flowchart showing an operation of a main part of the first embodiment.

FIG. 4 is a block diagram of a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE SIGNS 1 transmitter 2 receiver 4 first antenna 6 second antenna 7 antenna switching circuit 8 TDMA circuit 9 CODEC 12 control circuit 20 receiver circuit 1 21 receiver circuit 2

Claims (2)

[Claims] 1. A wireless communication device for transmitting a call message requesting a return of a response message to a base station via an antenna, a plurality of antennas each having a different directivity, and an antenna switching circuit for switching the antennas. A radio communication device comprising: a control circuit for controlling the antenna to be switched and the call message to be transmitted again when the response message is not received within a predetermined time. 2. A plurality of antennas each having a different directivity,
A wireless communication device comprising: an antenna switching circuit for switching the antenna, a tilt detecting unit for detecting a tilt of the wireless communication device, and a control circuit for switching the antenna based on the tilt detecting unit.