JPH1175238A - Method and device for controlling communication of mca system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the time to complete a line connection by varying the length of the transmission time of call signals to many stations by a transmitting means according to the number of free channels detected by a receiving means. SOLUTION: Each time a free channel detecting circuit 5 outputs a detection signal, a control part 6 counts their number and stores and holds it in a counter 64, and also stores the channel numbers of the free channels. The control part 6 has a time control function 65 for varying the length of the transmission time of call signals to respective mobile stations by the transmission part 7 according to the number of the free channels stored and held in the counter 64. The time control function 65 also has a function for varying the frequency of transmission of a call signal. Consequently, a communication line can securely be established in a short time irrelevantly to whether there are many dead channels.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-channel access (MCA) system used for mobile radio communication and the like, and more particularly, to an all radio channel without using a control channel for setting a communication channel. Are cyclically switched to select an idle channel.

[0002]

2. Description of the Related Art Conventionally, in the MCA system, a radio line (channel) dedicated to control is used as a communication line (channel) as used in a cellular radio telephone or a cordless telephone.
There is an MCA system provided separately from the MCA system, and a so-called non-local circulating MCA system in which all channels are cyclically switched to select an empty channel without setting a dedicated radio channel for control.

In the former MCA system using a control channel, one of the radio lines allocated for communication is used as a line exclusively for control (control channel). This is performed through a control channel. In the MCA system using such a control channel, one of the allocated radio channels is allocated as a control channel, and thus there is a problem that the number of communication channels is reduced by one.

[0004] In addition, a connection procedure for performing carrier sense on the control channel and the set communication channel is required. For this reason, there has been a problem that the connection procedure is complicated until the mobile stations enter a communication state. Furthermore, if the control channel is used by many mobile stations, the proportion of time that the control channel is occupied increases, so even if an attempt is made to transmit a signal such as an outgoing call on the control channel, the signal is being used by another station. There was also a problem that it was impossible to do so.

[0005] In the MCA system of the astatic circulation system, a mobile station in a standby state constantly scans and receives each assigned channel, and a base station sends out an idle signal to all available channels. . When a specific mobile station is selectively called from the base station, the following operation is performed. The base station stops the empty signal transmitted so far in one of the available channels and transmits a scan stop signal. On the other hand, when the mobile station receives the scan stop signal,
Scan reception on that channel is stopped, and a reception state is entered in order to detect the presence or absence of a selective call signal specifying the own station. The mobile station that has received the selective call signal designating its own station immediately emits a radio wave modulated with the response signal. Then, the base station that has confirmed the response signal from the mobile station immediately stops transmitting the scan stop signal. Therefore, the mobile stations other than the mobile station that has been selectively called restart the scan reception by stopping the transmission of the scan stop signal.

[0006] Such an MCA of the statically circulating system can effectively utilize the allocated speech channel,
Further, since a single control channel is not shared by many mobile stations, the connection procedure up to a call state can be simplified, and the problem that a call cannot be made can be solved. However, in this method, when the number of allocated communication channels increases, the number of channels that must be scanned increases. Therefore, the time required for the mobile station to acquire an empty channel, the time required for the calling station to call, and the time required for scanning are reduced. There is a problem in that the time required to stop the operation becomes long, and it takes a long time to determine the connection of the line.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and makes it possible to make effective use of the assigned communication channels and to make the connection procedure relatively simple. MC that can shorten the time until the connection of the line is determined in the MCA method of
The purpose is to provide the A method.

[0008]

According to claim 1 of the present invention,
Receiving means for sequentially scanning and receiving a plurality of allocated communication channels to detect the presence or absence of a call to the own station and detecting an empty channel; and, among a plurality of communication channels, an empty channel detected by the receiving unit. A transmitting means for transmitting a paging signal to another station via one of the above, wherein a transmission time of the paging signal to the other station in the transmitting means is determined by the transmitting means. In addition, a means for varying the length according to the number of empty channels detected by the receiving means is adopted.

According to a second aspect of the present invention, a receiving means for sequentially scanning and receiving a plurality of assigned communication channels to detect the presence or absence of a call to the own station and to detect a channel being used, and a plurality of communication channels. A communication control method for an MCA transmission / reception device having transmission means for transmitting a paging signal to another station via one of the channels other than the used channel detected by the reception unit, Means is provided for varying the length of the transmission time of the paging signal to the other station in the transmission means in accordance with the number of used channels detected in the reception means.

According to a third aspect of the present invention, the transmitting side transmits a scan stop signal including identification information designating a specific receiving side to a call signal to another station, and the receiving side transmits the predetermined identification information. Only when a scan stop signal including the scan stop signal is received, the scan reception is stopped to shift to a communication state with the transmission side.

In the communication device of the MCA system according to the fourth aspect, receiving means for sequentially scanning and receiving a plurality of assigned communication channels to detect the presence or absence of a call to the own station and to detect an empty channel, A communication device of the MCA system having a transmission unit for transmitting a paging signal to another station via one of the free channels detected by the reception unit among the plurality of communication channels, Counting means for counting the number of unused channels, and time for varying the length of the transmission time of the paging signal to the other station in the transmission means based on the number of available channels counted in the counting means. And control means.

According to a fifth aspect of the present invention, there is provided a number-of-times control means for decreasing and increasing the number of transmissions of the scan stop signal by the transmitting means based on the number of empty channels counted by the counting means. And Claim 6
Then, the counting means replaces the number of available channels with
The number of channels in use is counted, and the time control means varies the length of the transmission time of the paging signal to the other station in the transmission means according to the number of channels in use. Was.

According to a seventh aspect, the number control means includes:
The number of transmissions of the scan stop signal by the transmission means is increased or decreased according to the number of channels in use. In claim 8, the transmitting means includes identification information adding means for transmitting a scan stop signal including identification information designating a specific receiving side to a call signal for another station, and the receiving means comprises: Scan control means is provided for stopping scan reception only when a scan stop signal including identification information is received.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a communication control method and a communication device of the MCA system according to the present invention will be described in detail with reference to the drawings showing an embodiment.

FIG. 1 is a block diagram showing the configuration of an MCA-based base station employing the communication control method of the present invention.
In FIG. 1, a receiving unit 1 includes an amplifying circuit 3 for amplifying a reception signal of a channel specified by a local oscillation frequency from a PLL oscillation circuit 2, a demodulation circuit 4 for demodulating the amplified signal to obtain a demodulated signal. And an empty channel detection circuit 5 which receives the amplified signal and detects the presence or absence of an empty line signal.

A control unit 6 including a microcomputer
Determines which of the plurality of allocated speech channels to receive by controlling the local oscillation frequency output from the PLL oscillation circuit 2. Further, a scan control function 61 for sequentially switching the local oscillation frequency output from the PLL oscillation circuit 2 to sequentially scan and receive each channel is provided. The control unit 6
Has an identification information memory 62 storing identification information for specifying each station, and has a call detection function 63 for detecting whether or not a call signal is transmitted from any of the mobile stations. Further, each time a detection signal is output from the empty channel detection circuit 5, the number is counted and stored in the counter 64, and the channel number of the empty channel is stored.

The transmission section 7 amplifies the signal to be transmitted, which is output from the control section 6, and transmits the amplified signal to the transmission signal of the channel designated by the local oscillation frequency from the PLL oscillation circuit 2. And a modulation circuit 9 for performing modulation. The control unit 6 controls which local oscillation frequency is output from the PLL oscillation circuit 2 to determine which of the plurality of assigned communication channels to transmit the transmission signal.

The control unit 6 changes the length of the transmission time of the paging signal to each mobile station in the transmission unit 7 based on the number of available channels stored in the counter 64. A time control function 65 is provided. The time control function 65 also has a function of changing the number of times of transmitting the call signal. The identification information adding function 60 adds a scan stop signal and identification information of the called station to be transmitted to the MSK format signal to be transmitted, and adds a MSK format signal including a predetermined repetition pattern by the time control function 65. It has a function.

The audio circuit 10 includes an audio input / output device such as a microphone and a speaker. The audio signal input from the microphone is input to the transmission unit 7 as a signal to be transmitted via the control unit 6 and is transmitted as a transmission signal from the antenna. The signal received by the receiving unit 1 is demodulated and output as an audio signal from a speaker via the control unit 6. In the case of the relay operation, the received signal from the receiving unit 1 is output directly to the transmitting unit 7 via the control unit 6 without passing through the audio circuit 10.

FIG. 2 is a block diagram showing the configuration of an MCA mobile station employing the communication control method of the present invention.
It has the same elements as the base station configuration. In FIG. 2, a receiving unit 11 includes an amplifying circuit 13 that amplifies a reception signal of a channel specified by a local oscillation frequency from a PLL oscillation circuit 12, a demodulation circuit 14 that demodulates the amplified signal and obtains a demodulated signal. And an empty channel detection circuit 15 to which the amplified signal is input to detect the presence or absence of an empty signal.

A control unit 16 including a microcomputer
Determines which of the plurality of assigned communication channels to receive by controlling the local oscillation frequency output from the PLL oscillation circuit 12. Further, a scan control function 66 for sequentially switching the local oscillation frequency output from the PLL oscillation circuit 12 to sequentially scan and receive each channel is provided. Further, the control unit 16
Is a call that stores the identification information specifying the own station in the identification information memory 67, and determines that the call is directed to the own station when the received signal includes the identification information specifying the own station. A detection function 68 is provided. Further, each time a detection signal is output from the vacant channel detection circuit 15, the number is counted and the number of vacant channels is stored in the counter 69.

The transmission section 17 amplifies the signal to be transmitted, which is output from the control section 16, and transmits the amplified signal to the transmission signal of the channel designated by the local oscillation frequency from the PLL oscillation circuit 12. And a modulation circuit 19 for performing modulation. The control unit 16 controls which local oscillation frequency is output from the PLL oscillating circuit 12 to determine through which of the plurality of assigned communication channels the transmission signal is transmitted.

The control unit 16 determines the length of time for transmitting the paging signal to the base station in the transmitting unit 17 by the counter
There is provided a time control function 70 for changing the length of the short channel based on the number of empty channels stored in the memory 69. The time control function 70 also has a function of changing the number of times of transmission of the call signal. The identification information adding function 71 determines whether the transmitted M
A scan stop signal and identification information of the called station are added to the SK format signal, and a time control function is added.
70 is provided with a function of adding an MSK format signal including a predetermined repetition pattern.

The audio circuit 20 includes an audio input / output device such as a microphone and a speaker. The audio signal input from the microphone is used as a signal to be transmitted via the control unit 16 by the transmission unit.
It is input to 17 and transmitted as a transmission signal from the antenna. The signal received by the receiving section 11 is demodulated and output as an audio signal from the speaker via the control section 16.

When the above configuration is compared with the configuration of the claims, the receiving units 1 and 11 correspond to receiving means, and the transmitting units 7 and
17 corresponds to the transmission means, the scan control functions 61 and 66 correspond to the scan control means, the counters 64 and 69 correspond to the count means, and the time control functions 65 and 70 correspond to the time control means and the number control means. The identification information addition functions 60 and 71 correspond to identification information addition means.

In the above configuration, a case where a specific mobile station is called from a base station will be described as an example. Normally, the base station controls the reception unit 1 by the scan control function 61 provided in the control unit 6 to sequentially scan and receive a plurality of assigned communication channels. At this time, each time an empty channel is detected in the empty channel detection circuit 5, it is counted and the number of empty channels is stored in the counter 64. Similarly, in each mobile station, the receiving unit 11 is controlled by the scan control function 66 provided in the control unit 16 to sequentially scan and receive a plurality of assigned communication channels. At this time, each time an empty channel is detected by the empty channel detection circuit 15, it is counted and the number of empty channels is stored and held in the counter 69.

When calling a specific mobile station, the base station first causes the control unit 6 to send a scan stop signal to the MS.
The signal is converted to the K format, one of the available channels is designated, the signal is transmitted to the transmitting unit 7 as a signal to be transmitted, and transmitted from the antenna. At this time, in the scan stop signal converted into the MSK format, a scan stop code composed of a series of bits is repeated a number of times corresponding to the number of empty channels stored and held in the counter 69.

FIG. 3 shows the MSK format described above. Table 1 below shows an example of the relationship between the number of channels in use, the number of packets repeated in the scan stop signal, and the transmission time.

[0029]

[Table 1]

When the scan stop signal converted to the MSK format as described above is transmitted on any channel, each mobile station stops receiving the scan when it receives the channel and detects the scan stop signal. To fix the channel.

Next, a paging signal for calling a specific mobile station is subsequently converted from the base station into the MSK format and transmitted. Therefore, the mobile station that receives the call signal and detects the identification information that matches the identification information of the own station by the call detection function 68 immediately sends a response signal and establishes a communication line with the base station. At this time, when the number of used channels is small and the number of available channels is large, even if the scan stop signal transmission time is short, the time required for scanning and receiving all the used channels is short. Have room to detect the scan stop signal. In addition, when the number of used channels is large and the number of available channels is small, it takes a long time to scan and receive all the used channels. It becomes possible to receive the scan stop signal.

Thus, regardless of whether the number of available channels is large or small, the scan stop signal can be reliably detected and a communication line can be established in a short time. After receiving the scan stop signal converted to the MSK format and stopping the scan reception, squelch control such as conventional individual calling and continuous tone can be performed.

It should be noted that the following effects, which are expected by the MCA method of the astatic circulation method, can be naturally obtained. 1) Since a specific control channel is not set, it is unlikely that a line cannot be connected due to interference. 2) Since there is no need to set a control channel, the operation is simplified.

In the above description, a case where a specific mobile station is called from a base station has been described. The same applies to a case where a mobile station calls a base station. Further, although the description has been given based on the configuration of the base station versus the plurality of mobile stations, all the mobile stations may be used.

[0035]

According to the communication control method of the MCA system according to the first and second aspects, the length of the transmission time of the paging signal to another station can be reduced by:
Since the length can be changed according to the number of available channels,
It is possible to reliably establish a communication line in a short time regardless of the number of available channels.

Further, M according to claims 3, 4, 5, 6, 7, 8
According to the communication device of the CA system, the MCA which can obtain the above effects
A communication device of the system can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an MCA base station employing a communication control method of the present invention.

FIG. 2 is a block diagram showing a configuration of an MCA mobile station employing the communication control method of the present invention.

FIG. 3 is a diagram showing a format of an MSK signal.

[Explanation of symbols]

1,11 receiving unit, receiving means 5,15 free channel detection circuit 6,16 control unit 61,66 scan control function, scan control means 63,68 call detection function 64,69 counter, counting means 65,70 time control function, Frequency control function, time control means,
Number control means 60, 71 Identification information addition function, identification information addition means 7, 17 Transmitter, transmission means

Claims (8)

[Claims] 1. A receiving means for sequentially scanning and receiving a plurality of allocated communication channels to detect the presence / absence of a call to a local station and detecting an empty channel. A communication control method for use in an MCA transmission / reception apparatus having transmission means for transmitting a paging signal to another station via one of the detected idle channels, wherein the transmission means transmits a paging signal to another station. MC is characterized in that the length of time is variable in accordance with the number of vacant channels detected by said receiving means.
A method of communication control. 2. A receiving means for sequentially scanning and receiving a plurality of assigned communication channels to detect the presence or absence of a call to the own station and detecting a channel in use; Through one of the channels other than the active channel detected by the
MC having transmission means for transmitting a call signal to another station
In the communication control method used for the transmitting / receiving apparatus of the A system, the length of the transmission time of the paging signal to the other station in the transmitting means is varied depending on the number of the used channels detected in the receiving means. A communication control method using the MCA method. 3. On the transmitting side, a paging signal for another station includes:
A scan stop signal including identification information designating a specific reception side is transmitted, and the reception side stops scanning reception only when a scan stop signal including the predetermined identification information is received and communicates with the transmission side. 3. The communication control method of the MCA system according to claim 1, wherein the communication mode shifts to a communication state. 4. A receiving means for sequentially scanning and receiving a plurality of allocated communication channels to detect the presence or absence of a call to the own station and detecting an empty channel, and a receiving unit among the plurality of communication channels. A communication unit of the MCA system having a transmission unit for transmitting a call signal to another station through one of the detected empty channels, a counting unit for counting the number of empty channels detected by the receiving unit; Time control means for varying the length of the transmission time of the call signal to the other station in the transmission means based on the number of free channels counted by the counting means. MCA communication device. 5. The apparatus according to claim 4, further comprising a number control means for increasing or decreasing the number of transmissions of the scan stop signal by the transmission means based on the number of empty channels counted by the counting means. MC described in
A type communication device. 6. A receiving means for sequentially scanning and receiving a plurality of assigned communication channels, detecting presence or absence of a call to the own station, and detecting a channel in use, and a receiving means of the plurality of communication channels. A transmitting means for transmitting a paging signal to another station via one of the available channels other than the used channel detected by the communication unit. Counting means for counting the number of channels, and time for varying the length of the transmission time of the paging signal to the other station in the transmission means based on the number of used channels counted in the counting means. A communication device of the MCA system, comprising: a control unit. 7. A number control means for increasing or decreasing the number of transmissions of the scan stop signal by the transmission means based on the number of used channels counted by the counting means. 7. The MCA communication device according to 6. 8. The transmitting means includes a call signal for another station,
An identification information adding unit that transmits a scan stop signal including identification information that specifies a specific receiving side, the receiving unit includes:
The MCA according to any one of claims 4 to 7, further comprising a scan control unit that stops scan reception only when a scan stop signal including the predetermined identification information is received. Communication device.