JP2536220B2 - Paging system - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paging system, and more particularly to improvement of a battery saving method and a transmission signal sending method.

(Prior Art) As is well known, in a paging system, a control station connected to a public telephone network causes a base station arranged in each wireless zone to wirelessly transmit a blocked transmission signal,
This is a system that allows a receiver moving in a wireless zone to receive the signal.
The receiving operation is performed by the battery saving method as shown in the figure.

In FIG. 7, the transmission signal is composed of a preamble, a synchronization code, and a paging code that are divided into blocks, which are transmitted in each cycle TO. The receiver, in the period of one cycle, turn on only the receiver power briefly every short period t _s than the preamble signal length t _p endeavor to detect the preamble, check the receiver power supply and detects a preamble The synchronization code and the paging code are held and detected, and when the paging code ends (that is, when the transmission signal ends), the power supply of the receiving unit is turned off, and the sampling operation in the next transmission cycle starts. Since there is an unnecessary part for the receiver even during the reception period of the paging code, it is usual to turn off the power supply of the receiving part at the timing of the unnecessary part.

(Problems to be Solved by the Invention) In the conventional paging system described above, the receiver is
Since the receiver power is turned on for a short time even during the period without the paging code, there is extra power consumption other than the power required for reception. As a measure for reducing the power consumption of this portion, for example, it is conceivable to widen the sampling interval. However, if the sampling interval is widened, there is a problem in that a timing at which a transmission signal is missed occurs, and it is difficult to reduce power consumption.

In this type of paging system, the control station adopts a working / standby redundant configuration. However, if the working / standby switching is performed during operation, the receiver may lose the transmission signal, and a countermeasure is desired. ing. Regarding the transmission cycle, it may be desired to adopt a different cycle depending on the system, and it is desired to develop a configuration capable of flexibly coping.

The present invention has been made in view of such a problem, and an object thereof is to further reduce the power consumption of a receiver, and also to perform a working / standby switching and a transmission cycle change in a control station. In this case, it is an object of the present invention to provide a paging system in which a receiver can receive a transmission signal without any trouble.

(Means for Solving the Problems) In order to achieve the above object, the paging system of the present invention has the following configuration.

That is, in the paging system of the first invention, a control station connected to a public telephone network causes a base station arranged in each wireless zone to periodically wirelessly transmit a blocked transmission signal to move within the wireless zone. And a means for measuring the cycle of the transmission signal; a valid transmission of the next transmission signal estimated from the end point of the transmission signal based on the measured cycle. Means for turning off the power supply of the receiving unit within a period up to the head position.

In the paging system of the second invention, a control station connected to a public telephone network causes a base station arranged in each wireless zone to periodically wirelessly transmit a blocked transmission signal to move within the wireless zone. And a means for measuring the cycle of the transmission signal; a valid transmission of the next transmission signal estimated from the end point of the transmission signal based on the measured cycle. The control station includes a means for turning off the power of the receiving unit within a period up to the head position; a unit for restarting the period measurement when the valid head position cannot be detected within a predetermined time. Means for suspending transmission of a transmission signal to the base station within a period of at least one cycle when initializing.

Further, in the paging system of the third invention, a control station connected to a public telephone network causes a base station arranged in each wireless zone to periodically wirelessly transmit a blocked transmission signal to move within the wireless zone. And a means for measuring the cycle of the transmission signal; a valid transmission of the next transmission signal estimated from the end point of the transmission signal based on the measured cycle. The control station changes the transmission cycle, including means for turning off the power of the receiving unit within a period up to the start position; and means for restarting the cycle measurement when the valid start position cannot be detected within a predetermined time. A means for receiving a command and transmitting a transmission signal to the base station at an originally changed cycle after a lapse of a predetermined time whose lower limit is a predetermined time length for the receiver to detect an effective start position. It is characterized in that there.

(Operation) Next, the operation of the paging system of the present invention configured as described above will be described.

In the paging system of the first invention, the receiver measures the period of the transmission signal, estimates the effective start position of the transmission signal based on the measured period, and determines the effective start position of the next transmission signal from the end point of the transmission signal. The power of the receiver is turned off until the start position.

Therefore, the receiving unit of the receiver is supplied with power only when it is truly necessary for the receiving operation during the period other than the period measurement period, and the power consumption can be greatly reduced.

In the paging system of the second invention, the transmission signal generator is initialized when the control station switches between active and standby, but at that time, the transmission signal is transmitted to the base station for a period of at least one cycle. It will be canceled. As a result, a non-signal portion within a period of at least one cycle is formed in the transmission signal transmitted by radio. Then, since the receiver cannot detect the effective start position of the transmission signal, the period measurement operation is restarted and the same operation as in the first aspect of the invention is performed.

Therefore, even if the active / standby system is switched during operation, the receiver can reliably receive the transmission signal without losing sight of it.

Further, in the paging system of the third invention, when the transmission cycle is changed in the control station, the predetermined interval necessary for the receiver to detect the effective start position of the transmission signal in one or more cycles near the start thereof. Since the non-signal portion whose time length is the lower limit is formed, the receiver operates in the same manner as in the first aspect of the invention after measuring or re-measuring the transmission cycle. That is, the receiver can surely receive the transmission signal without losing sight as in the second aspect of the invention.

Thus, according to the third aspect of the invention, it is possible to provide a paging system that can flexibly meet the user's request.

(Example) Hereinafter, the Example of this invention is described with reference to drawings.

FIG. 1 shows the configuration of a paging system according to an embodiment of the present invention. In FIG. 1 (a), in the control station, the control units (1a, 1b) and the transmission signal generation units (2a, 2b) have a duplicated redundant configuration, one of which is the active one and the other of which is the standby. In response to calls from the public telephone network accepted by the input trunks 3, 3, ..., The active control unit handles subscriber verification, service menu verification, etc. according to the registered data, and the active transmission signal generator preamble and synchronization code. And generate a paging code. These are periodically transmitted to each base station via the output trunks 4, 4, .... In each base station, the transmitted signal is wirelessly transmitted from the antenna 6 into the wireless zone by the transmitter 5 as a radio frequency transmission signal. As a result, from the base station in each wireless zone, as shown in FIG. 2A, for example, a blocked transmission signal is repeatedly wirelessly transmitted at a constant period TO.

The above is a general operation similar to the conventional one, and the transmission signal is also similar to the conventional one in that a preamble is headed and a plurality of pairs of a sync code and a paging code are continuous to this. is there. The difference is that there is no signal for a period of at least one cycle TO, and the cycle may be changed. Details will be described later (fifth
(Fig. 6).

In addition, as shown in FIG. 1 (b), the receiver is a receiver unit.
When the power switch 33 is turned on, the power source including the battery 34 is immediately applied to the control unit 32, and the power is continuously supplied until the power switch 33 is turned off. On the other hand, the receiver 31 includes a control switch under the control of the controller 32.
Power is supplied only within a predetermined time when 35 is closed. Conventionally, as described above (FIG. 7), the reception operation is intermittently performed at intervals t _s shorter than the preamble length t _p , and the preamble is detected. The same operation as in Fig. 2 (b)
As shown in, the operation is performed without detecting the preamble.

Since it is not a requirement of the present invention whether or not the receiver has a display function, the alarm horn 37 which is a basic function is shown in FIG. 1 (b). That is, the signal received by the antenna 36 is subjected to demodulation processing and the like in the receiving unit 31 and enters the control unit 32, where it is determined whether or not it is a self-call and the sounding drive of the alarm horn 37 is performed.

Next, the operation of the receiver will be described with reference to FIGS. 2 and 3. After the period measurement, the receiver is
_Are divided into time t ₀₁ and time t ₀₂ , and each time is managed and operated (FIG. 2 (b)). Here, time t ₀₁ is the time for detecting the head synchronization code (effective head position). Further, the time t ₀₂ is the time from when the first synchronization code is received until the detection of the next synchronization code is started. Therefore, the control unit 32
Is equipped with the same sampling timer as before, and t ₀₁
It has a timer, a t ₀₂ timer, a counter, etc., and operates as shown in FIG.

In FIG. 3, in the first step 40, the period TO of the transmission signal is measured. This is executed when the power switch 33 is turned on, or when a need arises during the subsequent use, or the like. The TO measurement process, as will be described later in detail (FIG. 4), as shown in FIG. 7, and controls the opening and closing of the control switch 35 at short intervals t _s than the preamble length t _p, prior to the reception section 31 This is performed in a state in which the intermittent reception operation in the same manner as is performed.

If the cycle TO can be determined in this step 40 and the head synchronization code can be received based on that, the t ₀₂ timer is started (step 41) and the presence or absence of the paging code and the synchronization code following the head synchronization code is monitored. (Step 42). When the last paging code is completed, the determination result of step 42 is negative (NO), the control switch 35 is opened to turn off the power supply of the reception unit 31 (step 43), and the time-out of the t ₀₂ timer is waited. Yes (step 44).

Then, when the t ₀₂ timer times out, step 4
The result of the determination in 4 is affirmative (YES), and in the next step 45, the control switch 35 is closed to turn on the power supply of the reception section 31 and start the t ₀₁ timer. The timer value of the t ₀₁ timer is, for example, 0.125 seconds. Then, it is determined whether or not the t ₀₁ timer has timed out (step 46) or whether the synchronization code has been received (step 47).

If the synchronization code can be received before the t ₀₁ timer times out, the determination result of step 47 becomes affirmative (YES), the t ₀₁ timer is reset and the process returns to step 41,
Each operation after step 41 is repeated.

On the other hand, if the t ₀₁ timer times out before the synchronization code is received, the determination result of step 46 is positive (YE
S), the process returns to step 40 and the period TO is measured again. This is because it is considered that the period TO of the transmission signal has changed.

Next, details of the TO measurement process (step 40) will be described with reference to FIG. In FIG. 4, first, the value N of the counter for period measurement is set to N = 0 (step 51), the receiving unit 31 is made to perform the intermittent receiving operation at the interval t _s , and the reception of the preamble is waited (step 52). . If the preamble can be received, the determination result of step 52 becomes affirmative (YES), and the reception of the synchronization code is awaited while the power of the receiving unit 31 is on (step 53).

If the synchronization code cannot be received because the electric field strength is weak, the result of the determination in step 53 is negative (NO), and the reception of the preamble is waited (step 54). If the preamble cannot be received, the determination result of step 54 is negative (NO), the process returns to the first step 51 and the operation is performed again.

On the other hand, if the preamble can be received, the determination result of step 54 becomes affirmative (YES), and the process returns to step 53 to wait for the reception of the synchronization code. When the synchronization code is received, the determination result of step 53 becomes affirmative (YES), the process proceeds to step 55, the time until the reception of the synchronization code is measured, stored as a synchronization value, and the counter value N is incremented by 1. Next steps
Continue to 56.

In step 56, it is judged whether or not the value of the counter value N is 1. In this case, since N = 1, the determination result is affirmative (YES), waits for the end of the paging code (that is, the end of the transmission signal) (step 61), returns to the previous step 52, and returns to step 53 and Step 55 via 54
At step 56, the measurement memory of the period TO and the counter value N are incremented by 1, and the process goes to step 56.

In step 56, N = 2, so the determination result is negative (NO), the flow proceeds to step 57, and the difference value between the previous measurement value and the current measurement value is obtained. In this case, the previous measurement value is an incorrect value, and the difference value exceeds the error range, so the determination result in step 58 is negative (NO), and the routine proceeds to step 60.

In step 60, the present measurement value is stored as the previous measurement value, and the counter value N is set to N = 2. And
Wait for the end of the paging code (step 61), return to the previous step 52, and go through steps 53 and 54.
Do the same at 55 and come to step 56.

Since N = 3 this time, the determination result in step 56 is negative (NO), the difference value is obtained in step 57, and it is determined whether it is within the error range (for example, 0.03 seconds) (step 58). If it is within the error range, the determination result of step 58 becomes affirmative (YES), and it is determined whether or not the specified number of times (for example, 3 times) has been continued (step 59). If it is less than the specified number of times, the determination result of step 59 is negative (NO), the process proceeds to step 60, and the TO measurement described above is repeated.

Then, in step 59, if it is determined that the specified number of consecutive times has occurred, the determination result is affirmative (YES), the process proceeds to step 62, the average of the measured values for a predetermined number of times (for example, 10 times) is calculated, and the average value is calculated. Value and determine the value of t ₀₂ .

It should be noted that, in step 61, the receiver performs a normal reception operation, and therefore, if there is a call of itself, the sounding of the alarm horn 37 is performed as usual.

As described above, the receiver can measure the period TO and use the measured period TO to turn off the power supply of the reception unit 31 when there is no paging code. Therefore, the power consumption can be further reduced as compared with the conventional case.

Next, the operation of the control station according to the present invention will be described. In the control station, when switching between the control units 1a and 1b is performed, the fifth
As shown in the figure, from the operation time point of the new control unit (which is almost equal to the switching time point), for example, there is no signal in the period of one cycle without a transmission signal. This is because the new transmission signal generator is initialized, so that the receiver re-measures the period TO so that the transmission signal is received without fail.

Further, the control section also changes the transmission cycle, and FIG. 6 shows an operation flowchart including the above switching.

In FIG. 6, when the active / spare switching is performed and the new control unit is in an operable state, the determination result of step 71 is affirmative (YES), and the process proceeds to step 72 to initialize the new transmission signal generation unit, For example, the value of one cycle is set as the timer value, the TO timer is started, and the TO timer is timed out (step 73).

When the TO timer times out, the determination result of step 73 becomes affirmative (YES), and it is determined whether or not the timer value has been changed (step 74). If the timer value has not been changed, the determination result of step 74 is negative (NO), the TO timer is started (step 75), the preamble, the synchronization code, the paging code and the like are transmitted to the base station, and the process returns to step 73. That is, the first cycle after switching is in a no-signal state, and the transmission signal is transmitted as usual from the next cycle.

At the end of the transmission cycle (step 73), it is determined whether or not the timer value is changed (step 74). If there is a change, the determination result of step 74 is affirmative (YES), and the change timer is started (step 77). Wait for that timeout (step 78). This means that there is no signal in the first cycle after the cycle is changed, and this may be repeated a plurality of times if necessary. Note that the value of the change timer is set with the time t ₀₁ as the lower limit in order to secure the time t ₀₁ required for the receiver to detect the head synchronization code when the cycle is changed in the direction of the short cycle.

And when the change timer times out, step
The determination result of 78 is affirmative (YES), the new cycle value is set in the TO timer (step 79), the TO timer is started (step 75), and the change process is ended.

By the above measures, the receiver can correctly receive the transmission signal with low power consumption even if the transmission signal is switched or changed.

(Effects of the Invention) As described above, according to the paging system of the first invention, the receiver measures the reception period, estimates the effective start position of the transmission signal, and transmits the next signal from the end point of the transmission signal. Since the power to the receiver is turned off until the effective start position of the signal, power is supplied to the receiver only when it is truly necessary for the receiving operation in the period after the period measurement. There is an effect that power can be significantly reduced.

Also, according to the paging system of the second invention and the third invention, the receiver enables the period measurement to be restarted when the effective start position of the transmission signal cannot be detected at the estimated position, and the control station Since the non-signal portion is formed for a predetermined period when the transmission signal generator is initialized and when the transmission cycle is changed, the receiver can receive the transmission signal correctly without losing the transmission signal.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of each element in a paging system according to an embodiment of the present invention, FIG. 2 is a reception time chart, FIG. 3 is a receiver battery saving flowchart, and FIG. 4 is a transmission cycle (TO) measurement. 5 is a detailed flow chart of FIG. 5, FIG. 5 is a diagram showing the relationship between the operating state of the control unit and the transmission signal when the control unit is switched by the control station, and FIG. FIG. 7 is an operation flow chart of the control station of FIG. 1a, 1b ... Control unit, 2a, 2b ... Transmission signal generation unit, 3 ... Input trunk, 4 ... Output trunk, 5 ... Transmitter, 6 ...
… Antenna, 31 …… Reception part, 32 …… Control part, 33 …… Power switch, 34 …… Battery, 35 …… Control switch, 36 …… Antenna.

Claims (3)

(57) [Claims] 1. A control station connected to a public telephone network causes a base station arranged in each radio zone to periodically transmit a blocked transmission signal by radio, and a receiver moving in the radio zone receives the blocked transmission signal. And a means for measuring the period of a transmitted signal, the paging system adapted to:
Means for turning off the power supply of the receiving unit within a period from the end point of the transmission signal to the effective start position of the next transmission signal estimated based on the measured cycle; 2. A control station connected to a public telephone network causes a base station arranged in each wireless zone to periodically wirelessly transmit a blocked transmission signal, and a receiver moving in the wireless zone receives the blocked transmission signal. And a means for measuring the period of a transmitted signal, the paging system adapted to:
Means for turning off the power supply of the receiving unit within a period from the end time of the transmission signal to the effective start position of the next transmission signal estimated based on the measured cycle; the effective start position cannot be detected within a predetermined time And means for resuming the cycle measurement, and the control station suspends the transmission of the transmission signal to the base station within the period of at least one cycle when the transmission signal generator is initialized. A paging system characterized by that. 3. A control station connected to a public telephone network causes a base station arranged in each wireless zone to periodically wirelessly transmit a blocked transmission signal, and a receiver moving in the wireless zone receives the blocked transmission signal. And a means for measuring the period of a transmitted signal, the paging system adapted to:
Means for turning off the power supply of the receiving unit within a period from the end time of the transmission signal to the effective start position of the next transmission signal estimated based on the measured cycle; the effective start position cannot be detected within a predetermined time And a means for resuming the cycle measurement, wherein the control station receives a command to change the transmission cycle, and after a predetermined time elapses with a lower limit of a predetermined time length for the receiver to detect an effective start position. A paging system comprising: means for transmitting a transmission signal to a base station at an originally changed cycle.