JPH0681096B2 - Call channel specification method for mobile communication devices - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method of designating a call channel suitable for a mobile communication device for communication between mobiles such as automobiles and people, for example, a cordless telephone.

<Prior Art> In the conventional mobile communication, although it is possible to make a call when it is determined that there is no carrier by determining only the presence or absence of a carrier of a frequency to be received, that is, so-called carrier sense of a reception frequency, Not only the frequency to be received, but also the presence / absence of a carrier of the frequency to be transmitted is determined to enable communication in an empty channel where there is no carrier of either the receiving or transmitting frequency. Is being revised.

<Objects of the Invention> The present invention has been made in view of the above points, and an object of the present invention is to provide a communication channel designating method in a mobile communication device corresponding to the revision of the Radio Law.

<Structure of the Invention> In order to achieve the above-mentioned object, the present invention is a method of designating a call channel between mobile communication devices, wherein each mobile communication device is in a standby state and is to receive a call. The presence or absence of the carrier of the frequency of the channel and the carrier of the frequency of the call channel to be transmitted is determined, and the determination result is stored in the storage unit as 2-bit information for each call channel. The mobile communication device transmits 1-bit information obtained by logically operating the 2-bit information stored in the storage unit to the other mobile communication device, and the other mobile communication device receives the 1-bit information. And 1-bit information obtained by logically operating 2-bit information stored in the storage unit to search for an empty channel, and the other mobile communication device is The searched empty channel is used as a call channel, and a designation signal for designating the empty channel as a call channel is transmitted to the one mobile communication device, and the one mobile communication device is based on the received designation signal. The empty channel is used as a call channel.

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a multi-channel access (MCA) type mobile communication device to which the method of the present invention is applied.

This mobile communication device 1 includes a reception channel receiver 3 that receives radio waves from a counterpart mobile communication device (not shown) given via an antenna 2, a transmission channel receiver 4 that receives the transmission radio waves themselves, and a local unit. Oscillation signal to each receiver
The local oscillator 5 given to 3, 4 and the IF detection circuit 6 for converting the desired signal among the signals from the respective receivers 3, 4 into the intermediate wave frequency and detecting it, and the designation of the communication channel described later and other A microcomputer 7 for controlling, a transmitter 8 for modulating and transmitting a command signal and the like from the microcomputer 7, and a PLL circuit 9 for fixing the transmission / reception frequency are provided.

In the call channel designation method in the mobile communication device of this embodiment, first, each mobile communication device, that is, the first
The mobile communication device 1 shown in the figure and the mobile communication device of the other party (not shown) are in a standby state after the power is turned on, that is, in a standby state, in which the carrier of the frequency of the call channel to be received and the frequency of the call channel to be transmitted are set. The presence or absence of each carrier is determined and the determination results are stored in the storage unit of the microcomputer.

The determination of the presence / absence of a carrier in this communication channel, that is, carrier sense is performed by a carrier sense circuit provided in the IF detection circuit 6 of FIG. 1, and a determination signal corresponding to the presence / absence of a carrier, in this embodiment, A determination signal of "1" when there is no carrier and "0" when there is a carrier is given to the carrier determination input port 10 of the microcomputer 7 shown in FIG.

The microcomputer 7 is provided with a channel memory 11 for storing the determination result of the presence / absence of a carrier, and the determination result is stored in the channel memory 11 via the carrier determination input port 10.

For example, as a result of this determination, the channel memory 11 of the mobile communication device 1 stores the data shown in Table 1, that is, 2-bit information for each call channel, and the channel of the counterpart mobile communication device (not shown) is stored. The following description will be given assuming that the data shown in Table 2 is stored in the memory.

Note that Rr represents the frequency of the speech channel to be received, and Rt represents the frequency of the speech channel to be transmitted.

Next, at the start of transmission, the determination result is transmitted from one mobile communication device, for example, the mobile communication device 1 in FIG. 1 to the other partner mobile communication device (not shown).

At this time, in this embodiment, the data of Table 1 is not transmitted as it is, but the data obtained by ANDing Rr and Rt of Table 1 by the empty channel calculating means 12 of the microcomputer 7, that is, Table 3 The 1-bit information for each communication channel shown is transmitted.

On the other hand, the mobile communication device (not shown) determines the next empty channel by the empty channel calculating means of the microcomputer based on the data of Table 3 to be transmitted and the determination result of Table 2 stored in the channel memory. To search.

That is, the logical product of Rr and Rt in Table 2 is obtained to obtain the data shown in Table 4, and the data and the transmitted Table 3
As shown in Table 5, the logical product with the data of the above is set in the order of younger channels, and when there is no carrier, that is, when the channel becomes "1", the communication channel is set as an empty channel, and the other channels are all "0". And

Then, the other mobile communication device sets the searched empty channel, in this example, 3ch as the call channel, and transmits a designation signal for specifying the empty channel as the call channel to one mobile communication device 1, The mobile communication device 1 controls the empty channel calculating means 12 based on the received designation signal so that the empty channel 3ch is used as a communication channel.

In FIG. 2, reference numeral 13 is a serial data input port for inputting transmission and reception signals, and 14 is a PLL channel designation output for outputting a control signal for controlling the PLL circuit 9 based on the output of the empty channel calculation means 12. A port, 15 is a serial data output port for outputting the output of the empty channel calculating means 12 to the transmitter 8.

As described above, in the method of the present invention, in the standby state, each mobile communication device performs carrier sensing of the reception frequency and the transmission frequency of each call channel and stores the result of the carrier sensing. Since the result is transmitted from one mobile communication device to the other mobile communication device, and an empty channel is searched based on the result to make a call on the empty channel, there is no carrier for transmission or reception. You will be able to talk on the channel.

Further, in this embodiment, when transmitting the result of the carrier sense, since it is transmitted as the logical product data, the amount of data to be transmitted is small, and the communication channel can be designated at high speed. Become.

<Effects of the Invention> As described above, according to the present invention, each mobile communication device in the standby state determines the presence or absence of the carrier of the reception frequency and the transmission frequency, respectively, and stores the determination result. , The data of the judgment result is transmitted, the empty channel is searched by the data, and the call is started on the empty channel, so that the call can be made on the channel having no carrier of the transmission frequency and the reception frequency. .

Moreover, according to the present invention, at the start of transmission, the 2-bit information for each communication channel indicating the determination result is not transmitted as it is, but the 1-bit information obtained by logically operating the 2-bit information is transmitted. It will be less and the call channel can be specified at high speed.

[Brief description of drawings]

FIG. 1 is a block diagram of a mobile communication device to which the method of the present invention is applied, and FIG. 2 is a configuration diagram of the microcomputer of FIG. 1 ... Mobile communication equipment, 7 ... Microcomputer,
11 …… Channel memory, 12 …… Empty channel calculation means.

Claims (1)

[Claims] 1. A method for designating a call channel between mobile communication devices, wherein each mobile communication device, in a standby state, has a carrier of a frequency of a call channel to be received and a call channel to be transmitted. The presence or absence of a frequency carrier is determined, and the determination result is stored in the storage unit as 2-bit information for each communication channel. At the start of transmission, one mobile communication device stores the result in the storage unit. 1-bit information obtained by logically operating the 2-bit information is transmitted to the other mobile communication device, and the other mobile communication device receives the 1-bit information and the 2-bit information stored in the storage unit. The 1-bit information obtained by the logical operation is logically operated to search for an empty channel, and the other mobile communication device sets the searched empty channel as a communication channel. In addition, the one mobile communication device transmits a designation signal for designating the empty channel as a call channel, and the one mobile communication device, based on the received designation signal, sets the empty channel as a call channel. A method for specifying a call channel in a mobile communication device, comprising: