JPH04132321A - Battery saving system - Google Patents

Abstract

PURPOSE:To reduce power consumption and to transfer the mode to a synchronization lock operation immediately when out of synchronism takes place by discriminating whether or not a reception signal has a prescribed code form and detecting out-of-synchronism based on the result. CONSTITUTION:A microcomputer 42 monitors reception of a synchronizing signal and detects the synchronizing signal, than it is discriminated that the synchronization is established at that point of time and the mode is set to the control mode to bring a radio circuit 2 and a demodulation circuit 3 into the reception operating state only for a reception period of a frame belonging to its own equipment. That is, occurrence of out-of-synchronism is detected without reception of the synchronizing signal by discriminating whether or not a call signal consists of a BCH signal so as to detect out-of-synchronism. Thus, the reception of the synchronizing signal is not required, the power consumption is decreased and when out-of-synchronism takes place, it is detected and the synchronization locking is brought immediately.

Description

Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention relates to a battery saving method performed to reduce power consumption in a selective call receiver used in a selective call system, for example. .

(Prior Art) A selective calling system is conventionally known as one of mobile radio systems. In the selective calling system, for example, the seventh
A selective call signal as shown in the figure is used. That is,
The selective call signal is composed of a preamble signal and a plurality of batches (n batches in the figure), as shown in FIG. The preamble signal consists of a repeating pattern of "1" and "0". Each batch is time-divided into a synchronization signal SC and a plurality of frames (eight frames in the figure) as shown in (b). These frames are each (C)
As shown in (d), it is composed of multiple call words (2 words in the figure), and these call words include 1 as shown in (d).
ring signals are inserted. This calling signal is individually set in advance for each selective calling receiver, for example (3
1, 21) Consists of BCH codes. Also, this B
A parity bit is added to the rear end of the CH code.

When calling a desired selective call receiver, the calling party dials the telephone number corresponding to the selective call receiver to call the base station. Then, the base station first generates a paging signal that is given to the selective paging receiver in advance. Then, the paging signal is inserted into an empty paging word of the frame to which the selective paging receiver belongs among a plurality of frames constituting one batch, and is transmitted.

On the other hand, FIG. 8 shows an example of the configuration of a selective calling receiver. In the figure, a selective calling signal transmitted from a base station is received by a radio circuit 2 via an antenna 1, demodulated by a demodulation circuit 3, and introduced into a control circuit 4. The control circuit 4 converts the code of the demodulated selective call signal into
It is compared with the call code of the own machine stored in advance in the individual number code memory (ID-ROM) 5. When a match between the two codes is detected through this comparison, it is recognized that a call has occurred to the own device, and a sound signal is supplied to the speaker 7 via the drive circuit 6. Therefore, a ringing tone is generated from the speaker 7, thereby notifying the owner of the occurrence of the ringing. Note that the ringing tone is stopped when a stop switch (not shown) is pressed or a certain period of time has elapsed.

Incidentally, this type of selective call receiver generally performs battery saving in order to reduce power consumption and extend the life of the battery 8. That is, when synchronization with the selective call signal is established, a control signal is output from the control circuit 4 to the battery saving circuit 9. Then, as shown in FIG. 9, the battery saving circuit 9 saves the output voltage of the battery 8 to the wireless circuit 2 and the demodulation circuit only during the receiving period of the synchronizing signal SC and the receiving period of the frame G to which the own device belongs for each batch. 3, thereby setting the radio circuit 2 and demodulation circuit 3 to the receiving operation state.

Here, the reason why the synchronization signal SC is received for each batch even after synchronization is established is as follows.

In other words, the selective calling receiver is not always located in a location with good reception, and may be moved to a location outside of the service area, or may be located in a location where the field strength of the received radio waves has decreased due to the effects of fading. There are cases. In such a case, the selective call receiver is likely to lose synchronization with the selective call signal. If synchronization occurs, it will not be possible to detect even if a call signal addressed to the machine arrives, so if synchronization occurs, detect it as quickly as possible and perform synchronization pull-in operation. There is a need. For this purpose, even after synchronization is established, it is necessary to constantly receive the synchronization signal SC and monitor the reception state for the occurrence of synchronization loss.

(Problem to be solved by the invention) However, such conventional battery saving methods,
As described above, in addition to receiving the frame G to which the device belongs, it must also receive the synchronization signal SC, which still consumes a lot of power, and a solution to this problem has been desired.

Therefore, the present invention focuses on the above-mentioned circumstances and eliminates the need to receive a synchronization signal, thereby further reducing power consumption and extending battery life.Furthermore, in the event that synchronization occurs, it is detected and synchronization is immediately performed. The purpose is to provide a battery saving method that can be transferred to

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention focuses on the fact that the calling signal has a predetermined code format, such as a BCH code, and When synchronization with respect to the calling signal is established, the receiving operation is performed only during the receiving period of a predetermined frame in each batch of selective calling signals, and the receiving operation is stopped during other receiving periods, and the above-mentioned receiving Determining whether the signal received by the operation has the predetermined code format, and detecting out of synchronization based on the result,
When this out-of-synchronization is detected, an operation is performed to establish synchronization with the selective call signal.

Further, the present invention provides a method in which, when it is detected consecutively in multiple batches that the received calling signal does not have a predetermined code format,
Another feature is that this is recognized as an out-of-synchronization.

(Function) As a result, according to the present invention, if synchronization occurs due to some reason, the code format force f of the received calling signal no longer satisfies the predetermined format. Occurrence of deviation is detected. Then, at the time of this detection, it is possible to shift to immediate synchronization pull-in. therefore,
After synchronization is established, it is no longer necessary to receive a synchronization signal, and the receiving operation only needs to be performed during the receiving period of the frame to which the device belongs. Therefore, compared to the conventional method in which the machine receives not only the frame to which it belongs but also the synchronization signal, it is possible to reduce power consumption by not receiving the synchronization signal, thereby extending battery life. It becomes possible to do so.

Furthermore, according to the present invention, it is determined that synchronization has occurred when the code format of the received calling signal does not satisfy a predetermined format for multiple consecutive batches. If a predetermined code format is not satisfied, this can be prevented from being immediately determined as an out-of-synchronization, and the accuracy of out-of-synchronization detection can be improved.

(Embodiment) FIG. 1 is a functional block diagram showing the configuration of a selective call receiver to which a battery saving method is applied in an embodiment of the present invention. In this figure, the same parts as those in FIG. 3 are given the same reference numerals and detailed explanations will be omitted.

The control circuit 40 includes a BCH code determination circuit 41 and a microcomputer 42 as the main part of the control circuit. First of all, the BC) (sign determination circuit 41 determines whether or not the received calling signal is composed of a BCH code by performing a BCH code calculation on the received calling signal output from the demodulation circuit 3. If it is determined that the code is not a BCH code, a BCH non-detection signal is output to the microcomputer 42.

Part of the microcomputer 42 has, as its control function, a collation means 43 for collating the code of the received call signal with the code of the own device stored in the ID-ROM 5 to determine whether or not they match; A notification control means 44 for supplying a sound signal to the drive circuit 6 to generate a sound from the speaker 7 when the matching means 43 determines that the two codes match, and a battery saving control means 45 are synchronized. It has a disconnection detection means 46 and a synchronization establishment control means 47.

The battery saving control means 45 puts the radio circuit 2 and the demodulation circuit 3 into operation only during the reception period of the frame G to which the own device belongs for each batch of the selective call signal in a state where synchronization with the selective call signal is established. A control signal is output to the battery saving circuit 9 in order to

The out-of-synchronization detection means 46 determines that out-of-synchronization has occurred when the BCH code determination circuit 41 outputs a BCH non-detection signal for two consecutive batches in a state where synchronization is established.

The synchronization establishment control means 47 performs predetermined control to bring in synchronization when the occurrence of synchronization is detected by the desynchronization detection means 45.

Next, the battery saving method of this embodiment will be explained based on the above configuration. First, in a state in which synchronization with respect to the selective call signal is established, the microcomputer 42 of the selective call receiver determines, for each batch, whether the reception period for frame G to which the receiver belongs has come, for example in step 2a as shown in FIG. I'm monitoring whether or not. Then, each time the receiving period of frame G to which the own device belongs starts, in step 2b, the first
A control signal is output to the battery saving circuit 9. Therefore, the battery saving circuit 9 supplies the output voltage of the battery 8 to the radio circuit 2 and the demodulation circuit 3 only during a period corresponding to the reception period of the frame G according to the first control signal. Therefore, the radio circuit 2 and demodulation circuit 3 operate for reception only during the period corresponding to frame G, as shown in FIG. 4, and thereby the paging signal inserted in frame G is received.

Further, when the receiving period of frame G to which the own device belongs comes, the control circuit 40 uses the BCH No. 71 determination circuit 41 to determine whether the code format of the received paging signal is a BCH code (step 2C). If it is a BCH code, it is determined that the synchronization state is maintained and step 2d
, and here the code of the received call signal is stored in the ID-ROM.
5 (step 2d). As a result of this comparison, if it is detected in step 2e that both codes match, the microcomputer 42
determines that a call has occurred to its own machine and moves to step 2f, where it outputs a ringing signal to the drive circuit 6. Therefore, the speaker 7 generates a ringing sound, which allows the holder to know that a call has occurred. still,
This sound is stopped when the owner presses a stop switch (not shown) or when it is detected in step 2g that a certain period of time (for example, 10 seconds) has elapsed (step 2
h).

On the other hand, suppose that the selective calling receiver loses synchronization with the selective calling signal due to, for example, fading. In this case, a paging signal in the correct code format cannot be received during the frame reception period being set. Therefore, the BCH code determination circuit 41 generates a <BCH non-verification ratio detection signal as shown in FIG. 5, and the number of times this signal is generated is counted by the microcomputer 42 in step 21. and,
As shown in FIG. 5, when the BCH failure ratio detection signal is generated in two consecutive batches and the count value of the counter reaches "22", the microcomputer 42 determines that synchronization has occurred and steps 2J to 2k. , and execute synchronization establishment control here.

That is, as shown in FIG. 3, the microcomputer 42 first monitors whether or not the reception timing for synchronization pull-in has arrived in step 3a, and at each reception timing, in step 3b, the microcomputer 42 instructs the battery saving circuit 9 to
outputs a control signal. Then, the battery saving circuit 9 receives the synchronization signal SC according to the second control signal.
The output voltage of the battery 8 is supplied to the radio circuit 2 and the demodulation circuit 3 only for a period corresponding to the reception time length of . Therefore, the radio circuit 2 and the demodulation circuit 3 are connected to each other as shown in FIG.
The reception operation is performed only during a period corresponding to the reception time length of the synchronization signal SC in the batch cycle.

Every time this reception operation is performed, the microcomputer 4
In step 2, it is determined whether the signal output from the demodulation circuit 3 is a synchronization signal SC or a preamble signal.
Determine using c and 3d. Then, when a preamble signal is detected in a certain batch, a third control signal for shifting to continuous reception operation is output to the battery saving circuit 9 in step 3e. Therefore, the battery saving circuit 9 is in a continuous conduction state, which causes the wireless circuit 2
The output voltage of the battery 8 is continuously supplied to the demodulation circuit 3, and as a result, the radio circuit 2 and the demodulation circuit 3 are in a continuous receiving operation state as shown in FIG.

In this state, the microcomputer 42 performs step 3f.
The reception of the synchronization signal SC is monitored. When the synchronization signal SC is detected, it is determined that synchronization has been established at this point, and as shown in FIG. Control then shifts to setting the circuit 2 and the demodulation circuit 3 to the receiving operation state.

If the immediate synchronization signal SC is detected during the reception operation for synchronization pull-in, the process directly moves from step 3C to step 3g to establish synchronization.

As described above, in this embodiment, when synchronization is established, the radio circuit 2 and the demodulation circuit 3 are in the reception operation state only during the reception period of the frame to which they belong. Therefore, the radio circuit 2 and the demodulation circuit 3 do not receive the synchronization signal SC.
The reception operation time of the selective call receiver can be shortened, thereby making it possible to reduce the power consumption of the selective call receiver and extend the life of the battery 8.

Furthermore, since out-of-synchronization is detected by determining whether or not the calling signal is composed of a BCH code, the occurrence of out-of-synchronization can be detected without receiving the synchronization signal SC. Therefore, even if a synchronization loss occurs, it is possible to quickly shift to a synchronization pull-in operation and establish synchronization.

Furthermore, in this embodiment, synchronization is recognized as being out of synchronization when the code format of the calling signal is determined not to be BCH code for two consecutive batches. If this is not the case, this can be prevented from being immediately recognized as an out-of-moment, and as a result, out-of-synchronization can be detected with good accuracy.

Furthermore, in this embodiment, even when performing synchronization pull-in, the radio circuit 2 and demodulation circuit 3 are operated to receive only once per batch until the synchronization signal SC or preamble signal is detected, so synchronization establishment control is performed. In addition, battery saving can be carried out, thereby reducing power consumption during synchronization establishment control.

Note that the present invention is not limited to the above embodiments. For example, in the above embodiment, the code format of the calling signal is BCH.
Although the case where a code is used has been described, other code formats may be used. In addition, if there is enough room in the call word length, a specific code pattern is added to the call signal to detect whether synchronization is lost or not, and by detecting this code pattern, it is possible to check whether synchronization has occurred. It may be determined whether the

In addition, the control procedures and control contents of the battery saving control means and the synchronization establishment control means, the format of the selective calling signal, the circuit configuration of the selective calling receiver, the type of mobile radio station, etc. may be changed without departing from the gist of the present invention. It can be implemented with various modifications.

[Effects of the Invention] As described in detail above, according to the present invention, in a state in which synchronization with selective call signals is established, the reception operation is performed only during the reception period of a predetermined frame in each batch of selective call signals. and stops the reception operation during other reception periods, and determines whether the signal received by the reception operation has the predetermined code format, and detects out-of-synchronization based on the result. When this out-of-synchronization is detected, an operation is performed to establish synchronization with the selective call signal, making it unnecessary to receive a synchronization signal, thereby further reducing power consumption. It is possible to provide a battery saving method that can extend the battery life and also detect when synchronization has occurred and shift to an immediate synchronization pull-in operation.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram showing the configuration of a selective call receiver to which a battery saving method is applied in an embodiment of the present invention, and FIGS. 2 and 3 show the control procedure and control contents of the control circuit of the receiver. FIGS. 4 to 6 are timing diagrams for explaining the battery saving operation of the selective call receiver shown in FIG. 1, FIG. 7 is a diagram showing an example of the configuration of a selective call signal, and FIG. The figure is a circuit block diagram showing an example of the configuration of a conventional selective call receiver.
FIG. 9 is a timing diagram for explaining a conventional battery saving method. DESCRIPTION OF SYMBOLS 1... Antenna, 2... Radio circuit, 3... Demodulation circuit, 5... Individual number code memory (ID-ROM) 6.
...Drive circuit, 7...Speaker, 8...Battery,
9... Battery saving circuit, 40... Control circuit, 41... BCH code determination circuit, 42... Microcomputer, 43... Verification means, 44... Notification control means, 45... battery saving control means, 46
... Out-of-synchronization detection means, 47... Synchronization establishment control means.

Claims (2)

[Claims] (1) Comprising a base station and a plurality of mobile radio stations, the base station time-division multiplexes a synchronization signal and a plurality of frames into which paging signals each having a predetermined code format are inserted to generate one batch. and repeatedly transmit a selective paging signal consisting of at least this one batch and a preamble signal, and each of the plurality of mobile radio stations receives the selective paging signal transmitted from the base station and receives the selective paging signal. In a mobile radio system that performs an operation to at least notify the occurrence of a call when a paging signal addressed to the own device is inserted in a predetermined frame, the plurality of mobile radio stations are synchronized with respect to the selective paging signal. an intermittent reception means that performs a reception operation only during a reception period of a predetermined frame in each batch of selective call signals in an established state, and stops the reception operation during other reception periods; out-of-synchronization detection means for determining whether a received signal has the predetermined code format and detecting out-of-synchronization based on the result; and synchronization establishing means for performing an operation for establishing synchronization with the selective calling signal when the selective calling signal is received. (2) The out-of-synchronization detection means recognizes out-of-synchronization when it is detected consecutively in multiple batches that the received signal does not have a predetermined code format.
The battery saving method described in 1).