JPS58210730A - Channel selecting system - Google Patents

Abstract

PURPOSE:To grasp a channel corresponding to the mean value of received electric power of respective channels within a specific time and to select the channel of maximum received electric power securely in communication system of car telephone, etc., by detecting the level of the received electric power of each channel in the form of a time rate in the specific time. CONSTITUTION:The received electric power of a channel specified by a processor 7 is inputted from an input terminal IN to a received electric power detecting circuit 1 to be converted into a corresponding DC voltage, which is inputted to a comparing circuit 3 together with a specific reference value (DC voltage) outputted from a reference value generating circuit 2. The comparing circuit 3 compares both inputs with each other and outputs a signal when the DC voltage corresponding to the received electric power is greater than the reference value, and the signal showing that the DC voltage is greater than the reference value is stored in an input port 4. The processor 7, on the other hand, reads and executes instruction words in a program memory 6 stored with a control procedure successively. Thus, the address of the input port 6 is specified to read the storage contents and when it is confirmed that the received electric power is greater than the reference value, the value of a software counter provided in a buffer memory 5 is increased. After the same processing regarding all channels is performed, all channel numbers are compared with each counter value (frequency of surpassing of received electric power above reference value), and the maximum value is selected to specify the corresponding channel number, thus selecting the desired channel and performing acquisition.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a mobile communication system such as a car phone,
The present invention relates to a channel selection method for selecting a channel that can obtain the maximum received power from among a plurality of preset channels.

In a mobile device of a mobile communication system, conventional channel selection methods for obtaining the maximum received power from one radio wave (channel) include, for example, a standard that has several levels of received power. There was a method in which channels with received power equal to or higher than a predetermined reference value were selected and captured.

In this method, there is a possibility that received power equal to or higher than a predetermined reference value can be obtained from other channels, and it is not always possible to select a channel from which the maximum received power can be obtained.

In other methods, the received power is converted into a digital value, compared, and the channel with the maximum value is selected, but like the above method, the channel is selected based on the value read at a certain time. , there is a risk that the wrong channel will be selected due to the effects of fading and the like.

There is also a method of analog comparison and selection, but this requires a large number of parts in the receiver (mobile device) and a large number of man-hours for adjustment.

An object of the present invention is to eliminate the drawbacks of the prior art described above, and to provide an economical channel selection method that can reliably select the channel with the maximum received power from among a plurality of channels in a mobile device of a mobile communication system. It is about providing.

The configuration of the channel selection method according to the present invention is such that, in a mobile device of a mobile communication system having a switching function for a plurality of channels, a plurality of channels are selected according to a predetermined order by the control and processing of a processor of a control unit. Switch sequentially at predetermined time intervals, compare each received power for each channel with a reference value, count and store the number of times the received power exceeds the reference value, and after completing -C switching for all channels, compare the received power with the reference value. The channel with the highest frequency is selected and captured.

In short, by detecting the received power level of each channel at a predetermined time rate, we can determine what corresponds to the average value of each level within that predetermined time, and ensure selection of the channel with the maximum received power. The aim is to

Hereinafter, embodiments of the present invention will be explained based on the drawings.
The figure is a block diagram of the main parts of an embodiment of a control section of a mobile device using the channel selection method according to the present invention, and FIG. 2 is a flowchart thereof.

In this ζ, ■ is a received power detection circuit, 2 is a reference value generation circuit, 3 is a comparison circuit, 4 is an input port, 5 is a buffer memory, 6 is a program memory, 7 is a processor, 8 is the data bus.

First, in order to sequentially check the magnitude of each received power for a plurality of channels related to the target communication, the processor 7 specifies channels according to a predefined order.

The received power of the designated channel is inputted from the input terminal IN to the received power detection circuit 1, converted and output as a corresponding DC voltage, and is output together with a predetermined reference value (DC voltage) output from the reference value generation circuit 2. , the first input is to the comparison circuit 3.

The comparator circuit 3 compares the power of both humans as described in F, and when the DC voltage corresponding to the received power is equal to the reference value plate 1, it outputs a signal to that effect, and this signal is input to the human power port 4. Accumulated. .

On the other hand, the processor 7 sequentially reads commands from the program memory 6 storing control procedures and executes the corresponding processing as shown in the flowchart of FIG.

As a result, when the address of the manual port is specified and the stored contents are read, and it is confirmed that the received power is above the reference value, the value of the software counter provided in the buffer memory 5 is read. make progress.

It is checked at regular intervals whether or not this counter value has reached a predetermined number of times, and if it has reached the specified number of times, the counter value and the channel number are paired and stored in the buffer memory 5. Make me remember.

After performing the above processing in the same way for all specified channels, compare each of the above counter values (the number of times the received power has exceeded the standard value) for all channel numbers, select the maximum value, and then 7.19I to select and acquire the desired channel.

In this way, the function of detecting the received power at a time rate and selecting the best receiving channel is implemented in software, making the device inexpensive, compact, and lightweight.

The power consumption is low, and even greater effects can be achieved especially by using a general-purpose microprocessor as the processor.

As described in detail above, according to the present invention, it is possible to realize an economical channel selection method that can reliably select the one with the maximum received power from among a plurality of channels, thereby improving mobile communication. Significant effects can be obtained in making the system more economical and improving reliability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a main part of an embodiment of a control section of a mobile device using a channel selection method according to the present invention, and FIG. 2 is a flowchart 1 thereof. 1...Received power detection circuit, 2...Reference value generation circuit,
3... Comparison circuit, 4... Human power port, 5... Buffer memory, 6... Program memory, 7... Processor, 8... Data bus.

Claims (1)

[Claims] 1. In a mobile communication system having a switching function for a plurality of channels, the plurality of channels are sequentially switched at predetermined time intervals according to a predefined order by the control and processing of the processor of the control unit, Compare each received power with a reference value for each channel, count and store the number of times the received power exceeds the reference value,
A channel selection method characterized by selecting and capturing the maximum channel of the same number of times after all channels have been switched.