JP3080632B2 - Radio selective call receiver - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio selective calling receiver in a radio selective calling method, and more particularly, to a battery saving method of intermittent reception in order to reduce power consumption of a battery (battery). The present invention relates to a radio selective call receiver having a function.

[Conventional technology]

2. Description of the Related Art Conventionally, a radio selective call receiver (hereinafter, sometimes referred to as a receiver) having a battery saving function of this type of intermittent reception system performs intermittent reception operation at a preset first cycle during a standby period. ing. Then, the receiver is a digital radio signal (hereinafter, sometimes referred to as a radio signal) transmitted from a base station of the radio selective calling system and composed of a preamble signal, a synchronization signal, an individual selective calling signal, an information signal, and the like. When a preamble signal set to have a time width longer than the first cycle is received and detected from the receiver, the wireless signal receivable state is maintained after the detection until the end of the synchronization signal following the preamble signal. . Thereafter, the receiver receives only the data of the group to which the receiver belongs from among the individual call signals, the information signals, and the like in the radio signal in a second cycle longer than the first cycle and determined by the signal configuration length of the radio signal. In this case, when the data reception is completed, the operation returns to the intermittent reception operation including the first cycle.

[Problems to be solved by the invention]

In the above-mentioned conventional battery-preferred radio paging receiver of the intermittent reception system, the first cycle of the intermittent reception of the receiver is generally set on the premise of the processing of the busiest period of the system. The intermittent reception operation is performed in the first cycle. For this reason, the receiver performs the intermittent reception operation in the first cycle even when the receiver is outside the service area such as a subway, an underground shopping mall, or a part outside a building. There is a drawback in that power is wasted and the effective use period of the radio selective calling receiver per unit battery is shortened.

[Means for solving the problem]

The radio selective call receiver according to the present invention is shorter than the radio signal during a preamble signal search period for receiving a radio signal composed of a preamble signal, a synchronization signal, a selective call signal and an information signal intermittently transmitted from a base station. When an intermittent reception operation is performed in a first cycle and a preamble signal included in the radio signal is detected, synchronization is established by a synchronization signal subsequent to the preamble signal, and the intermittent reception is performed in a second cycle shorter than the first cycle. A radio selective call receiver having a battery saving function of performing a reception operation and performing an intermittent reception operation in the first cycle during a preamble signal search period after the end of the radio signal, wherein the reception electric field strength of the radio signal is reduced. Means for detecting and converting to a DC voltage corresponding to the reception electric field strength, and a reference voltage corresponding to a predetermined reception electric field strength Means for comparing the DC voltage with the reference voltage; and, as a result of the comparison by the comparison means, when the DC voltage is lower than the reference voltage, the preamble signal search period is longer than the first cycle. Means for performing an intermittent reception operation at a predetermined cycle.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

 FIG. 1 is a block diagram of an embodiment of the present invention.

In FIG. 1, 1 is an antenna, and 2 is a radio unit. The radio unit 2 amplifies the digital radio signal received by the antenna 1,
The signal is converted into an intermediate frequency band signal a. Reference numeral 3 denotes a demodulation unit, which demodulates the intermediate frequency signal a generated by the radio unit 2 to generate a baseband digital signal. 4 is a waveform shaping circuit,
The waveform of the digital signal demodulated by the demodulation unit 3 is converted into a waveform that can be read by the decoder 8. Reference numeral 5 denotes a rectifying / amplifying circuit, which rectifies and amplifies the intermediate frequency signal a generated by the radio unit 2 and generates a DC voltage b corresponding to the received electric field intensity. Reference numeral 6 denotes a reference voltage generation circuit, which generates a reference voltage c serving as a reference to be compared with the voltage b. The generated reference voltage c is, for example, set to the same potential as the voltage b obtained when the reception electric field strength of the radio signal corresponds to the sensitivity level of the receiver, that is, the threshold of the notification sound, and becomes the boundary point of the service area. The threshold of the notification sound matches, which is convenient.

Reference numeral 7 denotes a comparison circuit which compares the voltage b with the reference voltage c, and when the voltage b is lower than the reference voltage c, sets the intermittent reception cycle of the receiver to the decoder 8 to be longer than the first cycle. And a comparison signal d ("1") requesting the third period. The decoder 8 decodes the digital signal generated by the waveform shaping circuit 4, generates an intermittent reception control signal e from the decoded signal and the comparison signal d (“1” or “0”), and sends it to the constant voltage circuit 10. The intermittent reception control signal e controls ON / OFF of the constant voltage circuit 10 in a cycle determined by the decoded signal and the comparison signal d. The decoder 8 also has a writable read only memory (PROM)
When the selected calling number stored in the PROM 9 matches the individual calling number decoded from the individual calling signal in the decoder 8, the designated ringing signal is sent to the amplifier 11.
To send to.

The constant voltage circuit 10 supplies a stable power supply voltage to the radio unit 2, demodulation unit 3, waveform shaping circuit 4, rectification / amplification circuit 5, and comparison circuit 7, which constitute the receiver. ON / OFF is controlled by e. As a result of this control,
The supply of the power supply voltage for each of the above circuits of the receiver is
The ON / OFF cycle, that is, the ON / OFF cycle, that is, the cycle determined by the intermittent reception control signal e, controls the intermittent reception cycle of the receiver. The amplifier 11 amplifies the sound signal sent from the decoder 8, and the speaker 12 notifies the sound signal. 13 is a battery, 14 is a power switch, and a reference voltage generating circuit 6,
Power is supplied to the decoder 8, the constant voltage circuit 10, and the amplifier 11.

Here, the operation of one embodiment of the present invention will be described in detail with reference to the flowchart shown in FIG.

First, the power switch 14 of the radio selective receiver shown in FIG.
When turned on (step 201), the decoder 8 sets the constant voltage circuit 1
An intermittent reception control signal e that turns ON / OFF at 0 in a predetermined first cycle is sent to the constant voltage circuit 10. The constant voltage circuit 10 is ON / OFF controlled in the first cycle, and the receiver starts intermittent reception of the digital radio signal input from the antenna 1 through the radio unit 2, demodulation unit 3, waveform shaping circuit 4, and decoder 8. (Step 202). Thereafter, when a preamble signal in the wireless signal longer than the first cycle is received (step 203),
The decoder 8 decodes the preamble signal and the synchronization signal received subsequently (step 204), and receives only the data of the group to which the receiver belongs, which is included in the individual paging signal, the information signal, etc., following the synchronization signal. Intermittent reception control signal e for performing intermittent reception in the second cycle
The constant voltage circuit 10 performs ON / OFF control in the second cycle, and the receiver performs intermittent reception in the second cycle (step 205). The second cycle is determined by the signal configuration length of the digital radio signal.

When the radio selective calling receiver receives the data addressed to itself (step 206), the radio unit 2, the demodulation unit 3, the waveform shaping circuit 4, and the decoder 5 receive the radio signal, demodulate the waveform, and perform the waveform shaping. A decoding operation is performed, and finally a ringing signal is sent from the decoder 8 to the amplifier 11, which drives the speaker 12 to generate a ringing tone (step 207). If the data continues, the intermittent reception is continuously performed in the second cycle. When the data is completed, the decoder 8 sends the intermittent reception control signal e for turning on / off the constant voltage circuit to the constant voltage circuit 10 in the first cycle. Then, the process returns to the intermittent reception in the first cycle (step 20).
8). If the synchronization signal could not be received or decoded in step 204, the decoder 8 sends out the intermittent reception control signal e in the first period, and the receiver returns to intermittent reception in the first period.

On the other hand, if the preamble signal is not received in step 203, the intermediate frequency signal a
Is rectified and amplified by a rectifier / amplifier circuit 5 and a comparison circuit 7 compares a voltage b corresponding to the received electric field strength generated by amplification with a reference voltage c preset in accordance with the sensitivity level of the receiver. If the voltage b is smaller than the reference voltage c (step 210), the electric field strength required for receiving the radio signal cannot be obtained, that is, the receiver goes out of the service area. , The comparison signal d
This is reported to the decoder 8 via (“1”). Then, by the notification, the decoder 8 turns on / off the constant voltage circuit 10 at the third period via the intermittent reception control signal e so as to switch the intermittent reception period to the third period longer than the first period.
Control (step 211), and the receiver shifts to intermittent reception according to the third cycle.

Note that the comparison between the voltage b and the reference voltage c in the comparison circuit 7 is periodically performed in the first cycle or the third cycle. The reference voltage c is preset to the same potential as the voltage b obtained when the reception electric field strength of the radio signal corresponds to the sensitivity level of the receiver.

Step 203, 20 during the intermittent reception of the receiver in the third period.
Search for preamble signal and voltage as shown in 9,210
b, Comparison of reference voltage c is performed. Comparison circuit 7 in step 210
As a result of the voltage comparison in the above, when the voltage b is higher than or equal to the reference voltage c, the electric field strength necessary for receiving the radio signal has been obtained, and the electric field strength required for receiving the radio signal is compared with the comparison signal d (“0”).
, The decoder 8 sends an intermittent reception control signal e for performing intermittent reception in the first cycle to the constant voltage circuit 10 assuming that the receiver is within the service area, and performs intermittent reception of the receiver. Is returned to the first cycle.

〔The invention's effect〕

As described above, according to the present invention, when the radio selective calling receiver having the battery saving function by the intermittent reception is out of the service area and the radio signal cannot be received with the sufficient reception electric field strength, the period of the intermittent reception is set to the radio. By making the cycle longer than the period when the selective call receiver is in the service area, the average current consumption can be reduced and the effective use period of the wireless selective call receiver per unit battery can be extended, thereby improving convenience. , Which can greatly reduce operating costs.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is a flowchart showing details of the operation of the embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Antenna, 2 ... Radio | wireless part, 3 ... Demodulation part, 4 ... Waveform shaping circuit, 5 ... Rectification / amplification circuit, 6 ... Reference voltage generation circuit, 7 ... Comparison circuit, 8 ... Decoder , 9 ... PRO
M, 10 ... constant voltage circuit, 11 ... amplifier, 12 ... speaker, 13 ... battery, 14 ... power switch.

Claims (2)

(57) [Claims] 1. A preamble signal search period for receiving a radio signal including a preamble signal, a synchronization signal, a selective call signal, and an information signal intermittently transmitted from a base station with a first period shorter than the preamble signal. When the intermittent reception operation is performed and a preamble signal included in the radio signal is detected, synchronization is established by a synchronization signal subsequent to the preamble signal, and the data of the group to which the terminal belongs is received from the selective call signal, the information signal, and the like. Wireless interrogation receiver having a battery saving function of performing a discontinuous reception operation in a second cycle for performing a discontinuous reception operation in a first period during a preamble signal search period after the end of the radio signal. Means for detecting the reception electric field strength of the radio signal and converting it to a DC voltage corresponding to the reception electric field strength; Means for generating a reference voltage corresponding to the obtained reception electric field strength, comparison means for comparing the DC voltage with the reference voltage, and as a result of the comparison by the comparison means, when the DC voltage is lower than the reference voltage. Means for performing an intermittent reception operation at a predetermined period longer than the first period during a preamble signal search period. 2. When the intermittent reception operation is performed at a predetermined cycle longer than the first cycle, and when the DC voltage becomes equal to or higher than the reference voltage, a transition to the first cycle is performed. The radio selective call receiver according to claim 1, wherein