JP2878195B2 - Radio selective call receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a radio selective call receiver having a so-called battery saving function.

[0002]

2. Description of the Related Art In a radio selective calling receiver using a battery as a power source, it is necessary to keep the power consumption of a receiving unit low in order to keep the life of the battery long. Also, if a large capacity battery is equipped, the whole radio selective calling receiver becomes large,
Reducing the power consumption of the receiving unit is an important issue in reducing the size of the radio selective calling receiver.

For this reason, in the radio selective calling receiver, the receiving unit is not operated constantly, but is operated intermittently at predetermined time intervals to reduce the power consumption of the receiving unit. BS is abbreviated.) Control is generally performed.

Here, in order to reduce the power consumption of the receiving section, it is desirable to increase the time interval for the intermittent operation. However, if the time interval is too long, the radio selective calling receiver should normally receive the signal. The probability of failing to receive the radio signal increases, and the receiving function of the radio selective calling receiver may be impaired. For this reason, BS control in the radio selective calling receiver is generally performed by intermittently driving the receiving unit at time intervals that do not impair the receiving function.

[0005] However, regardless of the case where the radio selective calling receiver is within the radio signal reception area, such a short time until the radio selective calling receiver is out of the reception area where radio signals do not arrive. Performing the intermittent reception operation at a time interval means that power is consumed wastefully.

[0006] The radio selective call receiver disclosed in Japanese Patent Application Laid-Open No. Hei 4-304043 has been proposed as one means for solving such a problem. This radio selective calling receiver determines whether or not the radio selective calling receiver is within the reception area by detecting whether or not the synchronization signal is received, and detects a shift to outside the reception area. BS
By switching the control mode, the power consumption of the receiving unit is to be reduced. More specifically, in this radio selective calling receiver, when the mobile phone goes out of the reception area, the counting of the elapsed time from the time point when the mobile phone goes out of the service area is started. The intermittent driving of the receiving unit is performed at a first time interval, which is a relatively short time interval, until the elapsed time reaches the fixed time A, and after the elapsed time exceeds the fixed time A, the first time interval is set. The intermittent driving of the receiving unit is performed at a second time interval longer than the interval.

According to this radio selective calling receiver, if the time of leaving the reception area is shorter than the predetermined time A, the intermittent reception is performed at a short time interval. Even when it arrives, it is possible to quickly receive it. On the other hand, if the time during which the mobile phone is out of the reception area is longer than the predetermined time A, the time interval of the intermittent reception is switched to a longer time interval, so that the power consumption of the receiving unit can be reduced and the battery life can be maintained longer. Becomes

[0008]

In the above-described conventional radio selective calling receiver, the out-of-service transition is detected based on the fact that the synchronization signal is not received, thereby uniformly extending the intermittent reception interval. Therefore, there is a problem in that the establishment of synchronization after returning to the reception area may be hindered depending on the time interval of the intermittent reception after the transition to the out-of-service area. Hereinafter, this problem will be described.

First, as a mode in which the radio selective calling receiver shifts out of the reception area, a first case in which the radio selective calling receiver goes out of the transmission area where the radio wave emitted from the transmitting station reaches,
There are two cases in the second case where the radio selective calling receiver enters a place where radio waves are blocked such as a subway or a building in a transmission area.

Here, in the first case of the above two modes, it is rare that the operation for returning to the reception area is suddenly forced, so that the time interval of the intermittent reception when outside the reception area is set. There is no problem even if it is lengthened to some extent. In contrast, the second
In this case, it is required to immediately return to the reception area and establish synchronization for that purpose by canceling the radio wave cutoff state.If the time interval for intermittent reception is extended outside the reception area, this rapid synchronization This will hinder the establishment.

However, in the above-mentioned conventional radio selective calling receiver, a uniform method can be used without making a judgment as to whether the out-of-service area corresponds to the first case or the second case. Is used to switch the time interval of intermittent reception. For this reason, if priority is given to reducing the power consumption by lengthening the time interval, there may be a case where trouble occurs in quick establishment of synchronization for returning to the reception area. In order to prevent this problem from occurring, it is necessary to shorten the time interval of intermittent reception when the mobile terminal is out of the reception area, but if this time interval is shortened, power consumption cannot be reduced sufficiently. The problem arises.

In recent years, there has been a demand for a type of receiver (hereinafter, referred to as a scanning receiver) that uses a plurality of frequencies and searches for a transmission signal to be received while performing frequency scanning when the receiver is out of the service area. Is growing,
The above problem is particularly important in this type of scanning receiver. That is, since the current receiver cannot receive a plurality of frequencies at once, this type of scanning receiver searches for a synchronization signal in a transmission signal while sequentially selecting a plurality of frequencies. In proportion to the number of frequencies used, a time interval for searching for a synchronization signal for one frequency becomes longer. Therefore, as the number of frequencies to be searched for increases, the detection of the synchronization signal when the receiver is in the transmission area is delayed, and the time for shifting to the service area becomes longer. If the above-mentioned prior art is applied to such a scanning receiver, the time interval for searching for a synchronization signal per frequency is originally long, but this time interval is further extended by out-of-service transition. Therefore, the problem of the delay in detection of the synchronization signal when in the transmission area becomes remarkable.

The present invention has been made in view of the above-described circumstances, and can control the time interval of the intermittent operation of the receiving unit after the out-of-service transition at a time interval suitable for the out-of-service transition mode. It is an object of the present invention to provide a radio selective call receiver that can satisfy both quickness and low power consumption required for establishment of synchronization for restoration.

[0014]

In order to solve the above-mentioned problems, it is necessary to take a means for detecting the mode of the out-of-service transition when the radio selective calling receiver moves out of the service area. The inventor of the present application has made intensive studies on such means, and has concluded that using the following phenomena is effective in solving the above-mentioned problems. a. When the radio selective calling receiver enters a radio wave blocking area such as a subway, the state suddenly shifts from a state where a synchronization signal is received to a state where a synchronization signal is not continuously received. b. When the radio selective calling receiver goes out of the transmission area, the frequency at which the synchronization signal is not received gradually increases,
Eventually, the synchronization signal is not continuously received.

The invention provided below uses such a phenomenon to identify the mode of the radio selective call receiver moving out of the service area, and performs the intermittent operation of the receiving unit at a time interval suitable for the mode. It is.

According to a first aspect of the present invention, there is provided a radio selective calling receiver having a function of intermittently supplying power to a receiving section so that the receiving section intermittently receives a radio signal. Based on the radio signal received by the radio selective calling receiver, it detects that the radio selective calling receiver has shifted out of the reception area, and based on the reception status of the radio signal in the past fixed time until detecting the shift to the out of the reception area. A gist of the present invention is a wireless selective call receiver characterized in that a time interval for intermittently supplying power by the receiving unit is controlled.

According to a second aspect of the present invention, there is provided a receiving section which is supplied with power intermittently and receives and demodulates a radio signal.
A synchronizing signal detecting means for detecting a synchronizing signal of a fixed period included in the radio signal from an output signal of the receiving unit; and a synchronizing signal detecting signal generated by the synchronizing signal detecting means, An out-of-service transition monitoring means for detecting a transition of the radio signal to an out-of-reception area; and a control unit for determining whether a synchronization signal has been detected by the synchronization signal detection means when power has been supplied to the reception unit for a predetermined number of times in the past. History receiving means for storing a history, and when the out-of-service transition monitoring means detects a transition of the radio selective call receiver out of the receiving service area, the receiving unit based on the history stored in the history storing means. And a power control means for controlling a time interval for supplying power intermittently.

Further, in the invention according to claim 3, the power supply control means determines that the out of service area is out of service area by the out of service area transition monitoring means.
At the point in time when the past
Out-of-service transition monitoring means in the reception history of the synchronization signal
The step that led to the decision that the step was out of range
Except for the reception history of the synchronization signal,
In the received history, if the number of times the synchronization signal is not detected is less than a predetermined number, the power is intermittently supplied to the receiving unit at a first time interval. The radio selective calling receiver according to claim 2, wherein the power is intermittently supplied to the receiving unit at a second time interval longer than the first time interval.

[0019]

According to a fourth aspect of the present invention, the out-of-service transition monitoring means determines that the radio selective calling receiver is within a reception range by outputting the synchronization signal detection signal, and outputs the synchronization signal detection signal. The radio selective call receiver according to any one of claims 2 to 3 , wherein it is determined that the radio selective call receiver has shifted out of the reception area by not being output continuously for a predetermined number of times. Is the gist.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a radio selective calling receiver according to an embodiment of the present invention. In this figure, an antenna 101 receives a radio signal from a radio base station (not shown). Receiver 102
The operation of is controlled by a BS control signal e output from a power supply control unit 110 described later, and demodulates and amplifies a radio signal a received by the antenna 101, and outputs a demodulated signal b.

The bit synchronization section 103 generates a reproduction clock c for data sampling using a reference clock and a demodulated signal b from a not-shown transmission circuit. The address coincidence detection unit 105 samples the demodulated signal b using the reproduced clock c, and detects a coincidence between the demodulated signal b and the call number preset in the radio selective call receiver.
Is output.

The user interface control unit 106 outputs a detection signal i from the address coincidence detection unit 105 to notify the user of the call using the notification unit 107.

The synchronizing signal detecting unit 104 generates the reproduced clock c
Samples the demodulated signal b from the receiving unit 102, detects the synchronization signal pattern, and outputs a detection signal d representing the detection result to the synchronization signal monitoring unit 108 and the history holding unit 10.
9

The synchronization monitoring unit 108 receives the reception unit power ON signal e output from the power control unit 110, and
The detection result of the synchronization signal when the power supply 2 is in the ON state is monitored, and the in-range / out-of-range detection signal f is output based on the monitoring result. That is, the synchronization monitoring unit 108
When the synchronization signal is detected when the power supply of the receiver 102 is turned on, the in-range / out-of-range detection signal f indicating that the vehicle is in the service area is output. When the state that is not detected occurs N times in succession, the in-service / out-of-service detection signal f indicating out of service is output. N is a value given in advance, and is a parameter that determines the condition for transition to out of service area.

The history holding unit 109 includes the synchronization signal detecting unit 10
The presence / absence of the detection of the synchronization signal of No. 4 is held for M times from the latest one. Here, M is determined so as to satisfy at least the condition of M> N. FIG. 2 shows the history holding unit 109.
1 shows an example of the configuration. In FIG. 2, 1 to M
Are flip-flops, and when the input signal level of the clock terminal C rises, the data input terminal D
And input from the output terminal Q.
In the example of FIG. 2, the history holding unit 109 is constituted by a shift register in which these M flip-flops are cascade-connected as shown. The data input terminal D of the first-stage flip-flop is connected to the synchronization signal detector 104.
Is input. Further, a pulse signal is input to the clock terminal C of each of the flip-flops 1 to M, and the rising edge of the pulse signal causes
The writing of the detection signal d to the first stage flip-flop and the shift operation between the respective stages of the shift register are performed. According to the shift register, the detection history of the synchronization signal is held for M times from the latest. Then, M-bit history data indicating the presence or absence of the detection of the synchronization signals for the past M times is output to the output signal lines D0 to DM of each stage of the shift register. FIG. 3 illustrates M-bit history data output to the output signal lines D0 to DM in this manner. This figure 3
In FIG. 7, a bit of "1" indicates that a synchronization signal has been detected, and a bit of "0" indicates that a synchronization signal has not been detected.

The power control unit 110 controls the power of the receiving unit 102 based on the outputs of the synchronization monitoring unit 108 and the history holding unit 109.

The power supply unit 111 is a power supply for supplying power to each unit in the radio selective calling receiver. However, receiving unit 1
The power supply to the power supply 02 is performed under the control of the power supply control unit 110.

Next, the operation of this embodiment will be described. In this radio selective calling receiver, power supply control section 110 constantly monitors in-range / out-of-range detection signal f output from synchronization monitoring section 108. Then, when detecting the shift of the radio selective calling receiver to the outside of the service area based on the service area / out-of-service detection signal f, the power supply control section 110 executes the routine shown in the flow chart of FIG. First, the power supply control unit 110 reads, from the history holding unit 109, history data indicating whether or not a synchronization signal has been detected until the transition to the out of service area (step 11). Next, the number of times X where no synchronization signal is detected out of the past M times is counted, and X
-N is calculated and compared with a parameter K set in advance as a criterion for determining an out-of-service factor (step 12). In this comparison, if K> X−N, it can be considered that the synchronization signal is no longer received rapidly, so the power supply control unit 110 determines that the radio selective calling receiver is in an area where radio waves are temporarily interrupted. It is determined that it has entered (step 13). Therefore, the power supply control unit 110 turns on the power of the receiving unit at a predetermined first time interval with respect to the receiving unit 102.
A signal e is sent to perform BS control at the first time interval (step 14).

On the other hand, in the comparison in step 12, K ≦
In the case of X-N, it can be considered that the synchronization signal is not gradually received, so that the power supply control unit 11
0 determines that the radio selective calling receiver has gone out of the transmission area (step 15). Therefore, the power control unit 110
Sends the receiving unit power ON signal e to the receiving unit 102 at a second time interval longer than the first time interval, and performs the BS control at the second time interval.

When the BS control is started at the first time interval, the power supply control unit 110 thereafter executes a routine whose flow is shown in FIG. First, the power control unit 110
Determines whether or not a fixed time T has elapsed since the BS control was started at the first time interval (step 2).
1). Then, when the predetermined time T has elapsed, the BS control at the second time interval is started (step 22).

Next, with reference to FIG. 6, the BS control performed in this embodiment will be described in comparison with the prior art.
In FIG. 6, t represents the elapsed time from the point in time when the radio selective calling receiver moves out of the reception area.

First, (a) of FIG. 6A shows a receiving unit when K> XN in the comparison with step 12 described above and it is determined that the radio selective calling receiver has entered the radio wave blocking area. FIG. 6 shows the waveform of the power ON signal e.
(A) and (b) show the waveform of the receiving section power ON signal e in the conventional radio selective calling receiver under exactly the same conditions.

FIG. 6 (a) shows the receiving unit when K ≦ X−N in the comparison with step 12 described above and it is determined that the radio selective calling receiver is out of the transmission area. The waveform of the power ON signal e is shown, and FIG. 6B shows the waveform of the receiving section power ON signal e in the conventional radio selective calling receiver under exactly the same conditions.

As shown in these figures, in the conventional radio selective calling receiver, regardless of whether the mobile phone enters the radio wave blocking area or the mobile phone goes out of the transmission area, it takes a longer time interval to go out of service area. Intermittent reception is performed.

On the other hand, in the radio selective calling receiver according to the present embodiment, when entering the radio wave blocking area, intermittent reception is initially performed at short time intervals, and after a predetermined time T elapses, the intermittent reception is performed. Is switched to intermittent reception. On the other hand, when the mobile terminal goes out of the transmission area, intermittent reception is performed at a long time interval from the beginning. The optimum value of the time T differs depending on whether a subway is assumed as the radio wave blocking area or a basement of a building or the like. In the present embodiment, the time T is, for example, about 30 minutes. The intermittent reception at the first time interval is performed, for example, by turning off the receiving unit for about 10 seconds and turning it on for about 2 seconds. OFF for about a second
It is performed by turning ON for about 2 seconds.

As described above, when returning from the radio wave blocking area to the reception area, it is required to quickly establish synchronization. However, the conventional radio paging receiver is uniformly fixed due to out-of-service transition. Since it switches to intermittent reception at the time interval of 同期, it is difficult to satisfy both the request for quick synchronization establishment and the request for reduction in power consumption.

However, according to the present embodiment, since the method of switching the time interval of the intermittent reception as described above is adopted, the out-of-coverage area transition in which quick synchronization is required when returning to the reception area is required. If it is performed (that is, the vehicle enters the radio wave blocking area), intermittent reception is performed at a short time interval, and if the mobile terminal shifts out of the service area where quick synchronization establishment is not required when returning to the service area ( That is, intermittent reception is performed at a long time interval during (movement outside the transmission area), so that both the above-described request for quick synchronization establishment and the request for reduction in power consumption can be satisfied.

In FIGS. 6A and 6B, the power supply O of the receiving section is shown.
.., Etc. are added to the respective pulse waveforms of the N signal e. These indicate scan frequencies to be searched at each timing, assuming that the radio selective receiver is a scanning receiver. is there. It will be understood that the effect of the present embodiment is remarkably exhibited in the case of the scan receiver.

[0040]

As described above, according to the present invention, it is possible to control the time interval of the intermittent operation of the receiving section after the out-of-service area at a time interval suitable for the mode of the out-of-service area. This has the effect of satisfying both the requirements for quickness and low power consumption required for establishing synchronization.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a radio selective calling receiver according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration example of a history holding unit 109 according to the embodiment.

FIG. 3 is a diagram showing history data in the embodiment.

FIG. 4 is a flowchart showing the operation of the embodiment.

FIG. 5 is a flowchart showing the operation of the embodiment.

FIG. 6 is a diagram illustrating BS control performed in the embodiment in comparison with a conventional technique.

[Explanation of symbols]

 Reference Signs List 101 antenna 102 reception unit 103 bit synchronization unit 104 synchronization signal detection unit 105 address coincidence detection unit 106 user interface unit 107 reporting unit 108 synchronization monitoring unit 109 history holding unit 110 reception unit power control unit 111 power supply

Claims (4)

(57) [Claims] 1. A radio selective calling receiver having a function of intermittently receiving a radio signal by supplying power to a receiving unit intermittently, based on a radio signal received by the receiving unit. Detecting that the radio selective call receiver has moved out of the reception area, and based on the reception status of the radio signal within a predetermined time period until the transition to the outside of the reception area is detected, the receiving unit intermittently detects Wireless paging receiver for controlling a time interval for supplying power to a mobile phone. 2. A receiving section which is supplied with power intermittently and receives and demodulates a radio signal, and a synchronizing signal detecting means for detecting a synchronizing signal of a fixed period included in the radio signal from an output signal of the receiving section. An out-of-service transition monitoring means for detecting, based on a synchronization signal detection signal generated by the synchronization signal detection means, a transition of the radio selective calling receiver to a position outside the reception area; History holding means for holding a history of whether or not a synchronization signal has been detected by the synchronization signal detection means when power is supplied to the receiving section; and out of service area of the radio selective calling receiver by the out-of-service transition monitoring means. Power supply control means for controlling a time interval for intermittently supplying power to the receiving unit based on the history held in the history holding means when the transition of the data is detected. Radio selective calling receiver characterized by and. 3. The out-of-service switching monitoring unit includes:
At the time when it is determined that the area is out of the service area,
In the past reception history of the synchronization signal stored in the holding unit,
The out-of-service transition monitoring means determines that the out-of-service
Except for the reception history of the synchronization signal that was the basis for
In the reception history left in the history holding means, if the number of times the synchronization signal is not detected is less than a predetermined number, intermittently supply power to the reception unit at a first time interval, The radio selective call receiver according to claim 2, wherein if the number of times is equal to or greater than a predetermined number, the power is intermittently supplied to the receiving unit at a second time interval longer than the first time interval. Wherein said out-of-service migration monitoring unit determines the radio selective calling receiver intended to be received within by the synchronization signal detection signal is output, the synchronization signal detection signal is continuously a predetermined number of times The radio selective call receiver according to any one of claims 2 to 3 , wherein it is determined that the radio selective call receiver has moved out of the reception area by not being output.