JP3115166B2 - Wireless communication equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication device, and more particularly to a radio communication device for performing reliable communication.

[0002]

2. Description of the Related Art Conventionally, a radio communication device for performing simplex communication or semi-duplex communication has a calling station and a response station, and transmits a call signal from the calling station, and the response station transmits the call signal. When the signal is received, a response signal is manually returned to the calling station. Upon receiving the response signal, the calling station confirms the existence of the response station and starts communication.

[0003]

As described above, the conventional wireless communication apparatus starts communication after waiting for a response from the answering station in response to the call from the calling station. If there is no response from the answering station immediately after the end of the call, the existence of the answering station cannot be confirmed. It can be confirmed that it is not present. Therefore, it takes time to confirm the presence or absence of the answering station after the call from the calling station is completed, and communication may be performed even though the answering station is absent. become.

Accordingly, an object of the present invention is to provide a radio communication device which does not transmit an extra communication signal before confirming the presence of a response, and which can reliably confirm the presence or absence of a responding station. To provide.

[0005]

In order to solve the above-mentioned problems, a wireless communication device according to the present invention is a wireless communication device that performs communication between a calling station and a responding station using the same frequency for transmission and reception. The calling station transmits a call signal in response to the PTT input, and after this transmission, automatically returns to a receiving state regardless of the PTT input, and the answering station receives the call signal. Automatically sends a response signal to the calling station regardless of the PTT input,
After receiving the response signal, communication is started, and the calling station generates a beep from the time the PTT switch is turned on until the start of communication, and the response signal is transmitted within a predetermined time from the input of the PTT. If you do not receive
It is configured to generate a warning sound.

[0006]

According to the present invention, it is easy to confirm the existence of the answering station by generating a beep sound without establishing communication until a response to the call is confirmed, thereby eliminating unnecessary communication. I have.

[0007]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration block diagram showing an embodiment of a wireless communication device according to the present invention. When a user presses a PTT (Push To Talk) switch to start communication, a PTT input signal is input to the control circuit 1.
The control circuit 1 sends a call signal from the transmission circuit 3 to the antenna ANT via the antenna switching circuit 4 in response to the PTT input signal, and transmits the signal to the responding station.

On the other hand, a response signal automatically returned from the response station in response to the call signal is received by the antenna ANT and transmitted to the front end 5 via the antenna switching circuit 4. Well-known processing is performed in the front end 5 and I
The received signal that has been subjected to the intermediate frequency processing by the F circuit 6 is supplied to the carrier detection circuit 7. The carrier detection circuit 7
The carrier of the response signal is detected from the IF signal transmitted from the F circuit 6, and the detection signal is supplied to the control circuit 1. When receiving the detection signal, the control circuit 1 determines that a response signal has been received, starts communication, modulates the input signal input from the microphone with the modulation circuit 2, operates the transmission circuit 3,
The signal is transmitted to the responding station via the antenna switching circuit 4 and the antenna ANT.

A voice signal (communication signal) from the responding station is converted to an IF signal via an antenna ANT, an antenna switching circuit 4, a front end 5, and an IF circuit 6 at the same time as described above, and is output to a detection circuit 7. The audio signal detected by the detection circuit 8 is amplified by the low-frequency amplification circuit 9 and then output to a speaker.

[0010] Further, after transmitting the call signal, the control circuit 1
Until the carrier (response signal) is detected by the carrier detection circuit 7, a signal for generating a beep sound from the speaker is sent to the low-frequency amplifier circuit 9.

FIG. 2 is a timing chart for explaining the operation of the above embodiment. In response to the PTT input from the calling station, a calling signal is transmitted for a short time. After this transmission, it automatically returns to the receiving state regardless of the PTT input.
When the answering station receives this call signal, it automatically sends a short-time answer signal to the calling station regardless of the PTT input. Communication is started after the calling station receives the response signal. At this time, from the time the PTT switch is turned ON until the start of communication, the caller's wireless communication device generates the above-mentioned beep sound to make it easy to recognize the start of the call.

Here, if the caller has a PTT input, receives a maximum of 500 msec after a short transmission, and does not receive a response signal from the response station, communication cannot be started. Generates an audible alert to notify call failure.

The operation procedure of the above embodiment will be described with reference to the flowchart of FIG. First, after the PTT is turned on (step S1), the generation of a beep sound is started (step S2), and the calling signal is output for a short time (eg, 30
0 ms) (step S3), and it is determined whether there is a response from the responding station (step S4). Here, if there is a response, the generation of the beep sound ends (step S5), the transmission operation starts (step S6), and the communication starts (step S5).
7). Next, after the PTT is turned off (step S8), the transmission is terminated, and the process returns to step S1.

In step S4, if there is no response, after the beeping sound ends (step S10), a warning sound is started (step S11), and it waits until the PTT is turned off (step S12). When PTT is turned off,
The generation of the warning sound is terminated (step S13), and the process returns to step S1 again.

FIG. 4 is a timing chart showing the operation of another embodiment of the present invention, showing an example in which a relay station exists between a calling station and a responding station. When the relay station detects the transmission signal (call signal) from the calling station, the relay station sends the signal to the answering station,
A similar calling signal is transmitted.

[0016]

As described above, according to the radio communication apparatus of the present invention, communication is not established and a beep is generated until a response to a call is confirmed, so that unnecessary radio communication is performed. Communication can be eliminated.

[Brief description of the drawings]

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

FIG. 2 is a timing chart for explaining the operation of the embodiment shown in FIG.

FIG. 3 is a flowchart of an operation processing procedure of the embodiment shown in FIG. 1;

FIG. 4 is a timing chart showing the operation of another embodiment of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 control circuit 2 modulation circuit 3 transmission circuit 4 antenna switching circuit 5 front end 6 IF circuit 7 carrier detection circuit 8 detection circuit 9 low frequency amplification circuit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04B 1/16 H04B 1/38-1/58 H04B 7/24-7/26 H04Q 7/06-7 / 38

Claims (1)

(57) [Claims] 1. A response from a calling station using the same frequency of transmission and reception.
In a wireless communication device for performing communication between stations , the calling station transmits a calling signal in response to a PTT input.
After this transmission, automatically regardless of the PTT input
The answering station returns to the receiving state, and responds to the reception of the calling signal by the PTT.
Automatically directs the answering signal to the calling station, regardless of input
The calling station starts communication after receiving the response signal.
Starting, the calling station turns on the PTT switch,
Until the communication starts, a beep sound is generated and the P
If the response signal is not received within a predetermined time from the TT input,
A wireless communication device that emits a warning sound when the wireless communication device is used.