JPH0239617A - Multiple-channel receiving type radio calling receiver - Google Patents

Abstract

PURPOSE:To make it unnecessary for a user to switch channels by automatically scanning receivable channels and receiving one channel having the maximum electric field intensity out of the above-mentioned channels. CONSTITUTION:An electric field strength deciding circuit 4 successively measures the electric field intensity of all channels, send a signal for setting the oscillating frequency of a synthesizer oscillator 1 so that the channel having the maximum electric field intensity can be received, and automatically selects the channel having the maximum electric field strength. An intermittent reception control circuit 2 turns ON-OFF a receiver power source in a constant time cycle, and when a decoding circuit 3 detects a pull out, the control circuit 2 makes the electric field intensity deciding circuit 4 check the electric field strength extending over all the channels and automatically select the number of the channel having the maximum electric field intensity with the synthesizer oscillator 1. Thus, the title radio calling receiver can be obtained which automatically switches the receiving channel and can be used by the user without the awareness of the user's current position.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multi-channel reception type radio paging receiver having a function of automatically switching reception channels.

(Prior art) In conventional multi-channel radio paging receivers, the switching of the receiving channel is done manually, and the user has to be aware of his/her current location and switch to the appropriate receiving channel. Ta.

(Problems to be Solved by the Invention) An object of the present invention is to provide a radio paging receiver that automates the switching of reception channels and that a user can use without being aware of the area in which he or she is located.

(Means for Solving the Problems) A feature of the present invention for achieving the above object is that in a radio paging receiver capable of selective reception of a plurality of channels by controlling the oscillation frequency of a variable frequency local oscillation circuit, It has a field strength determination circuit that determines the field strength of the channel, a decoding circuit that decodes the received demodulated signal and detects synchronization loss, and an intermittent reception control circuit that turns on and off the operating power of the receiver at predetermined intervals. , when the operating power of the receiver is turned on, when synchronization is recovered from an out-of-synchronization state, or periodically at fixed time intervals, the field strength determination circuit is driven under the control of the intermittent reception control circuit. The present invention provides a multi-channel radio paging receiver in which the received field strength of all channels is measured and the oscillation frequency of the oscillation circuit is set so as to receive the channel with the strongest field strength.

(Function) In the above configuration, the receiver measures the received field strength of each channel periodically, when the power is turned on, or when synchronization is recovered, and adjusts the local oscillation circuit so as to receive the channel with the strongest field strength. Set the oscillation frequency. Therefore, the receiving channel is automatically switched to the channel with the strongest electric field strength, and the object of the present invention is achieved.

(Embodiment) FIG. 1 shows an embodiment of the present invention, in which 1 is a synthesizer oscillator;
2 is an intermittent reception control circuit, 3 is a decoding circuit, 4 is a field strength determination circuit, 5 is a demodulation circuit, 6 is an IF amplifier circuit, 7 is a mixing circuit, 8 is an RF amplifier circuit, and 9 is an antenna.

The field strength determination circuit 4 sequentially measures the field strength of all channels, and sends a signal for setting the oscillation frequency of the synthesizer oscillator 1 so that the channel with the strongest field strength is received. This ensures automatic selection of the channel with maximum field strength.

The intermittent reception control circuit 2 turns the receiver power on and off at predetermined time intervals, and when the decoding circuit 3 detects a loss of synchronization, it checks the field strength across all channels in the field strength determination circuit 4. The channel number having the maximum electric field strength is automatically selected by the synthesizer excavator 1.

Note that when the radio paging signal is in the form of a burst, it is preferable to perform intermittent reception at a cycle shorter than the burst length of the signal in order to receive stiffness.

Roughly, in response to continuously transmitted radio paging signals,
It is preferable to perform intermittent reception in synchronization with a cycle in which a signal addressed to the receiver may be transmitted.

FIG. 2 is a timing chart in this embodiment,
This shows how the reception channel changes.

In the example, the number of reception channels is 5, and when the power is turned on, all channels (r+ to f5) are received sequentially and the level is measured, and as a result, channel number 2 has the maximum electric field strength.
Set channel 2. After that, synchronization was lost, and as a result of another determination of the electric field strength, channel 3 was found to have the highest electric field strength, so channel 3 was set.

Note that it is obvious that the single synthesizer oscillator may be an oscillator switched by a plurality of crystal oscillators.

(Effects of the Invention) As explained above, the receiver implementing the present invention automatically scans the receivable channels and receives the channel with the highest electric field strength, so there is no need for the user to switch channels. There is an advantage.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a receiver according to the present invention, and FIG. 2 is an operation time chart of the device shown in FIG.

Claims (1)

[Scope of Claim] A radio paging receiver capable of selectively receiving a plurality of channels by controlling the oscillation frequency of a variable frequency local oscillation circuit, comprising: a field strength determination circuit for determining the field strength of a reception channel; and a received demodulated signal. A decoding circuit that decodes the signal and detects out-of-synchronization, and an intermittent reception control circuit that turns on and off the operating power of the receiver at predetermined intervals. When synchronization is recovered from , or periodically at regular intervals, the field strength determination circuit is driven under the control of the intermittent reception control circuit to measure the received field strength of all channels, and the received field strength of all channels is measured. 1. An oscillation frequency of the oscillation circuit is set so as to receive a multi-channel radio paging receiver.