JPH0653889A - Selective call receiver - Google Patents

Abstract

PURPOSE:To attain low power consumption by preparing a mode for receiving all the same calls and giving priority to a receiving rate and a mode for receiving a call only once and selecting battery life with priority and switching these modes. CONSTITUTION:A timer 2 is driven when a power supply switch is turned on, and at the time of detecting a preamble signal, a timer 1 is driven and sink detection and address detection are repeated. At the time of detecting a preamble signal P1 within a receiving area, no power is supplied to a radio part during the period of transmission including P2. When a preamble signal P3 is transmitted, the measurement of the timer 1 ends and power is supplied to the radio part correspndingly to the timer 1, the preamble signal P3 is detected and power is supplied to the radio part. When a preamble signal P4 is transmitted, no power is supplied to the radio part. When a preamble signal P5 is transmitted, the measurement of the timer 1 ends and power is supplied to the radio part correspondingly to the timer 1. In this case, the 1st mode is the period of signals P1, P5, P6 and the 2nd mode is the period of signals P2 to P4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a selective call receiver, and more particularly to a battery saving (intermittent reception) system.

[0002]

2. Description of the Related Art A conventional selective call receiver is disclosed in Japanese Patent Laid-Open No. 62-62.
Genus POCSA, as described in 160830.
The G code system has become popular. This system has a configuration in which a substantially infinite batch continues after the preamble signal (bit synchronization signal). The service system of a domestic service company transmits every 30 seconds, and in order to increase the reception rate, the same call (including message) is sent every 30 seconds.
Has been sent twice. Therefore, it has a call prevention period of 1 minute. When the call transmission is completed, the signal speed is switched from 512 bps to 300 bps or a stoppage of the wave until the next transmission. Therefore, when the sync signal is no longer detected, the receiver side supplies power to the radio unit only for the detection of the next preamble signal.

[0003]

In the above-mentioned prior art, power is supplied to the radio unit for reception by the radio unit, which is much larger than reception by the self, which is generally said to be about 2 / day. It does not contribute to the improvement of power consumption.

Therefore, an object of the present invention is to provide a mode in which all the same calls transmitted a plurality of times are received and the reception rate is prioritized.
It is intended to provide a selective call receiver with a long battery life by providing two modes in which the same call sent multiple times is received only once and battery life is prioritized, and by switching between these modes. is there.

[0005]

A radio unit for receiving and demodulating a modulated signal transmitted by repeating a call a plurality of times,
In a selective call receiver having a power supply unit that intermittently supplies power to the wireless unit according to a control signal, a first mode for supplying the control signal so as to receive all the same calls transmitted a plurality of times. A second providing the control signal so that the same call sent multiple times is received only once
A selective call receiver having a mode, a selection unit for selecting the first mode and the second mode, and a mode display unit for displaying which mode the selection unit selects.

[0006]

In a system in which the same transmission (calling) following the preamble signal is repeated twice every 30 seconds, as in Japan, for example, the preamble signal is always received and the radio unit is set to the receiving state to make the same calling. The first mode of receiving twice and the detection of the next preamble signal when a preamble signal is detected are prohibited, and the preamble signal is thinned out, so that power is not supplied to the radio unit for the second reception of the same transmission. And a second mode. When the reception condition is good, the second mode is set to significantly extend the battery life.

[0007]

The details of the present invention will be described below with reference to Examples. FIG. 1 is a block diagram of a selective call receiver according to the present invention. A desired radio frequency is demodulated by a radio unit 2 including a discriminator via a built-in antenna 1 and converted into a rectangular wave by a waveform shaping circuit 3. The power supply control circuit 4 that supplies power to the wireless unit 2 and the waveform shaping circuit 3 is controlled by the control unit 5. The control unit 5 has bit synchronization with a received signal, frame synchronization, battery saving means for reducing power consumption such as the wireless unit 2, and an address signal from the wireless unit 2 in which the peculiar call number of the receiver is written.
The comparison with the data from M6 (unique call number storage means) is performed with error control, and the comparison means for determining whether or not the call is performed is controlled.

When the call is confirmed, the message data following it is stored in the memory 9 (storage means). Also,
An alarm device 8 such as a buzzer, an LED or a vibrator via the alarm drive circuit 7 notifies the user that there is a call. The stored message is sent to the LCD drive circuit 10 via the control unit 5 by the external operation member 13 including switches, and is displayed on the LCD display 12. The power switch 13a, which is a part of the external operation member, basically turns off the power switch 13a when the user does not want to receive a message and extends the battery life. A clock signal is sent from the crystal oscillation circuit 11 to the control unit 5 and the LCD drive circuit 10. The message processing unit 14 including the power supply control circuit 4, the control unit 5, the memory 9, the LCD drive circuit 10, and the oscillation circuit 11 is configured by a one-chip microcomputer. A battery 15 supplies power to the selective call receiver.

FIG. 2 is a flow chart of the intermittent operation of the wireless unit according to the present invention. In the present embodiment, it is assumed that the calling number and the message of itself are continuously transmitted twice at intervals of 30 seconds and the wave is stopped when the transmission is completed. The POCSAG code format has a transmission rate of 512 bps. The transmission continues for up to 26 batches starting with the preamble signal (18 words). One batch consists of 17 words, and consists of a sync signal (synchronization codeword) and the following eight frames. One frame consists of two words,
One word consists of 32 bits. Also, the calling number of itself is “42016” (: frame 0).

The receiver is "powered on" by the power switch
When (20) is performed, a control signal is sent to start a timer having a cycle of 1 second and to supply power to the wireless unit for a short time of several tens of ms, and the LCD display 12 indicates that the mode is the first mode.
Proceed to "Start timer 2 / first mode display" (21) displayed by. In the embodiment, the first mode display is when "Ec" is not displayed, and "21" is displayed in step 21.
The "Ec" mark is turned off. Then, the power is supplied to the radio section to judge whether the received signal is a preamble signal or not. When the preamble signal is not detected, power is not supplied to the radio unit until the time measurement of the timer 2 is completed. When the time measurement of the timer 2 is completed, the "timer 2 is started again.
The display returns to "mode display" (21) and the preamble signal detection is repeated. When the preamble signal is detected, power is supplied to the wireless unit until the subsequent sync signal is detected.
Then, the process proceeds to "stop timer 2" (23), which stops the operation of the timer 2. Next, let the power supply to the radio section to detect the preamble signal "Timer 1
Start "(24). Timer 1 is a 1-minute cycle timer. When timer 1 is operated, it is determined whether the preamble signal has become a sync signal.
Proceed to (25). If the sync signal is not detected within the predetermined time, the process returns to "start timer 2 / first mode display" (21). If a sync signal is detected here, power is supplied to the wireless unit at the timing of its own frame (: frame 0) and the process proceeds to "Call number identical?" (26) for comparison with the own call number. "Receiving process" (2) that receives and stores the subsequent message signal when the calling number is
Proceed to 7). Then, the process proceeds to "no sync detected" (28) in which the sync signal is detected again. When a sync is detected, the process proceeds to "Call number identical?" (26) again. When the sync signal is not detected due to the end of the transmission, the process proceeds to "turn off wireless unit power" (29), which suspends power supply to the wireless unit for detecting the calling number of the sink and the own frame. That is,
All power supply to the radio unit is stopped. Then, it is judged whether or not the measurement of the timer 1 is finished, "Timer 1 finished?"
Proceed to (30). When timer 1 finishes measuring 1 minute,
A control signal is sent from timer 1 and power is supplied to the radio section, and it is judged whether it is a preamble signal or not "preamble?"
Proceed to (31). When the preamble signal is detected, the "Ec" mark is displayed to indicate to the "second mode display" (32) that the second mode is informed. After that, similarly, power is supplied to the wireless unit and the same operation is repeated until a sync signal is detected. If the preamble signal is not detected, proceed to "Stop timer 1" (33), which stops the function of timer 1, and then restart "timer 2 and display the first mode" to detect the preamble signal.
Proceed to (21) and repeat the above operation.

In the embodiment, the determination of step 28 is made once with or without sync. However, for example, when the sync signal cannot be detected three times in succession, the process may proceed to step 29.

FIG. 3 is a timing chart of each part of FIG. Transmission is performed in a cycle of 30 seconds, and a preamble signal (P1, P2, P3 ... P6) is sent to the head of each transmission. For example, it takes 30 seconds between P1 and P2. In the figure, the timer 2 operates when the power switch is turned on, and the timer 1 operates when the preamble signal is detected. Then, sync detection and address detection are repeated. In the embodiment, since the frame is 0, the sync detection and the address detection are continuously supplied with power to the wireless section. The control signal to the radio unit for sync detection and address detection is shown as "timer 3 signal". When the transmission stoppage is detected by "Sink not detected?" (28), power is not supplied to the wireless unit for signal detection except for timer 1 until power is supplied to the wireless unit by timer 1. . That is, when the preamble signal P1 is detected in the reception area, P
The power is not supplied to the wireless unit during the transmission including 2.
Then, when the preamble signal P3 is transmitted, the timer 1
The measurement is completed, the power is supplied to the wireless unit corresponding to the timer 1, the preamble signal P3 is detected, and the power is supplied to the wireless unit for sync detection and address detection. Similarly, no power is supplied to the wireless unit when transmitting the preamble signal P4. Then, when the preamble signal P5 is transmitted, the measurement of the timer 1 is finished, and the power is supplied to the radio unit corresponding to the timer 1. If the carrier is outside the reception area and the preamble signal P5 is not detected as in the case of P5, the timer 1 is switched to the timer 2,
It takes a few seconds to find the preamble signal
The operation is to search for a preamble signal that supplies power to the wireless unit for a short time.

The power supply section signal is a (combined) signal obtained by combining the timers 1, 2, and 3, and the power is supplied to the radio section while the timer is ON.

The first mode is preamble signals P1 and P
5 and P6, and the second mode is the preamble signal P2,
The period is P3 and P4.

FIG. 4 is a display example of the LCD display according to the present invention. (A) is a reception standby display in the first mode, and the current time (10:25) is displayed.
(B) is a reception standby display in the second mode, in which the current time (10:25) and "Ec" indicating the second mode are displayed.

As described above, when the preamble signal is received, the subsequent batch signal is received. Therefore, in the reception area, the detection of the preamble signal is performed once every two times for the transmission of the preamble, and the radio unit operates intermittently for a maximum of 30 seconds in a cycle of 1 minute.
The remaining 30 seconds are completely inactive.

The mode display means allows the wearer to know the reception status.

[0018]

As described above, according to the present invention, when the transmission is confirmed, the power supply to the radio unit which consumes a large amount of power is stopped in the next transmission cycle. Machine can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram of a selective call receiver of the present invention.

FIG. 2 is a flowchart of an intermittent operation of a wireless unit according to the present invention.

FIG. 3 is a timing chart of each part of FIG.

FIG. 4 is a diagram showing an example of a display on the LCD display of the present invention.

[Explanation of symbols]

 1 ... Built-in antenna 2 ... Radio part 3 ... Waveform shaping circuit 4 ... Power supply control part 5 ... Control part 6 ... EEPROM 7 ... Alarm drive circuit 8 ... Alarm device 9 ... Memory 10 ... LCD drive circuit 11 ... Oscillation circuit 12 ... LCD display 13 ... External operation member 14 ... Message processing unit 15 ... Battery

Claims (1)

[Claims] 1. A radio unit for receiving and demodulating a modulated signal transmitted by repeating a call from a base station a plurality of times, and a power supply unit for intermittently supplying power to the radio unit according to a control signal. In the selective call receiver, the first mode for supplying the control signal so as to receive all the same calls transmitted a plurality of times and the control signal for receiving the same call transmitted a plurality of times only once. Selective call reception comprising: a second mode to be supplied; selection means for selecting the first mode and second mode; and mode display means for displaying which mode the selection means selects. Machine.