JPS61102835A - Wireless transmitting receiving system - Google Patents

Abstract

PURPOSE:To make a cost low-priced, to prevent simultaneous outgoing and to reduce the communication inability by transmitting and receiving by the same frequency between a main body and a terminal device, changing the time length of the call signal for every terminal device and entering the communication condition after discrim inating that other terminal device will not generate before and after a call signal is sent from the terminal device. CONSTITUTION:Before the terminal device 2 generates a call signal, first, the device enters a receiving condition and it is confirmed whether other terminal devices 3-5 are communicating with the main body 1 or not. At respective terminal devices 2-5, the time of the call signal is set so that it may become the longest in the sequence according to the importance. For example, when the priority sequence of the terminal devices 2-5 is the sequence of the terminals 2-5, the time length is four seconds for the terminal device 2, three seconds for the terminal device 3, two seconds for the terminal device 4 and one second for the terminal device 5. In this way, the higher the priority is, the easier the communication condition is entered, and the disturbance such as the same frequency and the simultaneous call can be avoided. Since communica tion can be executed by the same frequency, the main body 1 and the terminal devices 2-5 can be low-priced with a simple constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a wireless transmission/reception system.

[Background technology]

Conventionally, a wire transmission/reception system consists of a main body and multiple terminal devices, and each of the main body and the terminal device is provided with a transmitting/receiving section to enable mutual communication. Different frequencies were assigned, and the main body was equipped with filters corresponding to each. In this one,
This method requires as many crystal oscillation circuits as the number of channels assigned to the terminal, which has the disadvantage of increasing cost. Furthermore, if the number of stations is the same, there is a drawback that if 61 terminals' transmit at the same time, they will be confused and communication will be impossible.

[Purpose of the invention]

The purpose of the present invention is to reduce costs by sending and receiving calls on the same frequency between the main unit and the terminal, and to prevent simultaneous calls and eliminate confusion when calls are made from the terminal at the same time on the same frequency. be.

[Disclosure of the invention]

In Figure 1, (1) is the main body, (2), (3), (4
), (6) are the terminals that constitute the wireless transmission/reception system, and the main unit t1+, the terminals (2), (3
), (4), and (5) all have the same frequency transmitter/receiver (
(not shown) to enable mutual communication.

Now, the case where the terminal device (2) calls the main body (1) will be explained using the operational diagram of FIG. 2. Terminal (2
) first enters the communication state before sending a ringing signal,
Check whether the other terminals (3), (4), (5) are communicating with the main unit (tl). Other terminals (3), (4), (
6) is not making a call, it sends a calling signal to call the main body (1). When other terminals (3), +4+, +5+ are communicating, it waits until the end of the communication, and sends a calling signal after detecting the end of the communication. After transmitting the calling signal, it enters the receiving state again, confirms that only the terminal device (2) has issued the calling signal, and only after confirmation communicates with the main unit ill. At this time, each terminal (2), (3
), (4), (5) K is set so that the important one has the longest call signal time depending on its importance. For example, if the priorities of terminals (2), (3), (4), and (6) are in the order of terminals (2), (3), (4), and (5), then The time length is determined by the terminal (2
) is 4 seconds, terminal +311-i3 seconds, terminal (4) is 2
seconds, and the terminal (6) is 1 second. In this way, the higher the priority, the more letters of communication! This is because it is easy to enter δ, and avoids the confusion of simultaneous calls on the same frequency.Also, since it is possible to use the same frequency, the main unit [+1, terminal device (2)]
, (3), (4), and (6) can all be made easily and inexpensively.

〔Effect of the invention〕

As described above, the present invention transmits and receives data at the same frequency between the main body and the terminal, so there is no need to assign a frequency to each terminal, and there is no need to provide a filter on the main body, so the configuration can be simplified. It is simple and inexpensive, and it can also be done by changing the length of the paging signal between the terminals and communicating after determining that no other terminal is calling after sending the paging signal from the terminal. Since the system enters the state, it is possible to prevent confusion when calls are made from terminals at the same time, and it is also possible to prioritize each terminal.

[Brief explanation of drawings]

Figure 1 is a block circuit diagram of an embodiment of the present invention, and Figure 2 is the same operation as above. It's Roach Sate. +11...Body, (2), (3), (4), (6)・
...terminal device. Agent Patent Attorney Ishi 1) Chief Uetsutsu 1 Diagram

Claims (1)

[Claims] (1) In a wireless transmission/reception system consisting of one main body and a plurality of terminal devices, each of which is provided with a transmitting/receiving section so that they can communicate with each other, the main body and the terminal devices transmit and receive data at the same frequency. In this way, the time length of the paging signal is changed for each terminal, and the communication state is entered after determining that no other terminal is making a call before and after sending the paging signal from the terminal. A wireless transmission/reception system characterized by: