JP2890929B2 - Radio selective call receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio selective call receiver for receiving a message contained in a call signal transmitted from a base station by a radio frequency carrier, and more particularly to a radio selective call receiver suitable for receiving a message signal with a serial number. It relates to a call receiver.

[0002]

2. Description of the Related Art A radio selective paging receiver (hereinafter abbreviated as a receiver) in a paging system using radio frequency signals is modulated by a digital selective paging signal including a paging number (address) signal and a message signal and transmitted from a base station. Receiving the radio frequency signal, demodulates the signal into the digital selective calling signal, and decodes the signal into the calling number signal and the message signal. When the calling number signal matches the calling number stored in the memory built into the receiver, the notifying operation such as sound and vibration by the notifying means such as a speaker and the message display by the message displaying means are performed, and the receiver is called. Inform that there is.
In recent receivers of this kind, it is possible to receive a message without a sound by operating a switch of a receiver carrier. That is, in the no-sound reception mode, every time a paging signal from the base station is received, a message signal included in the paging signal is stored in a memory built in the receiver and received by the display means. Normally, only the number of message signals stored in the memory is displayed. The receiver carrier recognizes the presence or absence of the stored message signals from the display, and displays these message signals on the display means by operating the switch.

Such a receiver having such a no-sound reception mode is disclosed in U.S. Pat. S. Patent No. 4,412,217 (1
October 25, 983) "PAGE WITH VI
SIBLE DISPLAY INDICATING
STATUS OF MEMORY (Pager with Visible Display Indicator Status of Memory) ". That is, this U.S. S. The receiver disclosed in Japanese Patent No. 4,412,217 receives a call signal, accumulates a message signal included therein, displays the number of received and accumulated message signals, and displays the number of the received message signals in accordance with the reception order. It has functions such as assigning numbers and facilitating selective display of messages.

[0004] The reception of a message without a ringing sound according to the prior art as described above enhances the confidentiality of a call or a message addressed to a receiver carrier, and contributes to an expansion of the use of the receiver.

On the other hand, at the time when a call signal addressed to the user is transmitted from the base station as a radio frequency signal,
If the receiver carrier is out of service area or in a tunnel, the call signal will not be received by the receiver. In the case of a receiver which necessarily generates a ringing tone, the above-mentioned lack of reception easily leads to a call from the caller again, so the problem is small. The receiver may not recognize the lack of reception at the receiver, which may cause serious problems depending on the content of the transmitted message.

[0006] In order to allow the receiver carrier to confirm whether or not the reception has been lost, the base station sets the head of each of the message signals in the selective call signal for each subscriber (wireless selective call receiver) at the beginning. The method of inserting serial numbers has recently been adopted. According to this method, since the serial number is displayed together with the message on the display means of the receiver, the lack of reception is recognized by the receiver carrier, and can be easily remedied by contacting a paging service company or the like.

[0007]

However, the above U.S. Pat. S. Prior art receivers, including Patent No. 4,412,217, are not sufficiently capable of receiving such sequenced message signals. That is, in these conventional receivers, the serial number is only displayed on the display means as a part of the received message signal, so that the receiver carrier can confirm the absence of the reception by checking the serial number. The number must always be remembered. Not only is the burden on the receiver carrier,
The reliability of the recognition of reception loss cannot be ensured.

Accordingly, it is an object of the present invention to provide a radio selective calling receiver that facilitates recognition of the above-mentioned reception loss by a receiver carrier.

[0009]

A to an aspect of the present invention a radio selective call receiver according is composed of a call number signal and a message signal
Receiving means for receiving a radio signal from the base station; detecting means for detecting a serial number included in the message signal and indicating a transmission order for each receiver from the base station ; First storage means for storing a serial number, and a message corresponding to the first serial number;
Second storage means for storing a second serial number corresponding to a message signal received before receiving the message signal;
The first and second serial numbers satisfy a predetermined condition.
Notification means for performing notification when the first and second
Display means for displaying the serial numbers together .
Also, the notifying means includes a first serial number, a second serial number,
Notification if the difference between the two is greater than or equal to a predetermined value.
Is preferred. In addition, notification by notification means and wireless communication
Incoming call notification when receiving a signal is based on different signal formats.
It is preferable to be informed.

Also, a radio selective call receiver according to the present invention.
Is a digital signal containing a calling number signal and a message signal.
Radio frequency signal modulated by selective paging signal from base station
Receiving means and digital selection of this radio frequency signal
Means for demodulating the signal into a call signal, and a call number
Means for decoding into a signal signal and a message signal, and the decoding
Selectively generate a call alert in response to the output of the means
Means and a table for selectively and visually displaying the output of the decoding means
Transmission means transmitted from the base station at arbitrary time intervals.
Means for receiving a series of said message signals
The transmission order of each receiver from the base station included in the
Means for detecting the serial number to be indicated, and the output of the detecting means
Storage means for temporarily storing the latest serial number
And the latest sequence number of the series
The message signal received immediately before the message signal
At least the latest serial number corresponding to the last received serial number
To store the message signal to which it belongs
Storage means, and a second storage means based on the output of the first storage means.
Means for subtracting the output of the stage;
Means to alert at one time, the latest serial number and
Means for displaying the last received serial number together.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

The radio selective calling receiver of one embodiment of the present invention shown in FIG. 1 demodulates a radio frequency signal transmitted from a base station (not shown) and received by an antenna 11 into the digital selective calling signal. A receiver / demodulator 12 for generating a digital selective calling signal Sa, and determining whether or not a calling number signal included in the digital selective calling signal Sa matches its own address stored in an address memory 13 built in the receiver. And a decoder 14 for detecting and recognizing a call addressed to itself. A microprocessor (hereinafter abbreviated as CPU) 20 receiving an output of the decoder 14 includes a sequence of instructions to be executed, that is, a program memory (not shown, the same applies hereinafter) storing a program, and a program for designating a read address of this memory. A counter, an instruction decoder for decoding an instruction read from the memory and supplying a control signal corresponding to the instruction to the inside and outside of the CPU, and an operation unit for performing various operations such as arithmetic operation and logical operation via an accumulator;
It incorporates a system clock generator for generating a system clock and a data bus, and operates according to a program read from the program memory. Decoder 1
4 indicates that the received call number signal matches the own address from the memory 13, the CPU 20 instructs the call alert signal generator 16 to generate a call alert signal, and responds to this instruction to generate a signal. The unit 16 generates a call alert signal PA. If the CPU 20 detects the lack of reception by means and procedures described later, the CPU 20
Instructs the reception loss alert signal generator 17 to generate a reception loss alert signal, and in response to this instruction, the signal generator 1
7 generates a reception missing alert signal FA. These signals PA and FA are amplified by an amplifier 18 and applied to a speaker 19 to generate a sound at an audible frequency.

On the other hand, when a match between the received call number signal and the memory 13 is detected by the decoder 14, the decoder 1
The message signal destined for this receiver supplied from 4 to the CPU 20 is stored in the message memory 21. This memory 21 is composed of a random access memory (RAM), and receives a received message by the digital selective calling signal Sa.
Is stored together with the above-mentioned serial number. Register 2
2 stores the serial number of the message signal received immediately before the reception of the received message.
Temporarily stores the serial number of the message signal just received. These received messages and the associated serial numbers are displayed on a message display unit 31 composed of a liquid crystal display panel via a display control unit 30. Note that a receiver with a data display employing a microprocessor itself belongs to the public domain, and its configuration is described in U.S. Pat. S. Patent No. 4,41
No. 2,217, etc., the description is limited here to the parts related to the gist of the present invention.

Referring to FIG. 2A showing an example of a signal format of the digital selective calling signal Sa, this signal Sa is a so-called POCSAG (Post Office).
Code Standardization Advi
Sorry Group) standard format (see CCIR Recommendation 584). That is, the signal Sa is composed of a preamble signal P having a length of 576 bits formed by repeating "1" and "0" and a plurality of batches each including 17 codewords (each codeword has a length of 32 bits). Consists of These codewords constituting each batch, except for the first one for synchronization (SC), form two adjacent frames to form one frame, respectively, to form a total of eight frames. The call number signal A consists of one code word and is inserted at a predetermined frame position in the above eight frames. Following the call number signal A, a message signal M consisting of a number of message code words M0-Mn according to the size of the message to be transmitted is inserted. In the remaining time slots assigned to these signals A and M, a predetermined idle code I is inserted.

A plurality of combinations of the call number signal A and the message signal M can be included in one call signal Sa. Each of these signals is configured to allow distinction between the calling number signal A and the message signal M 32
MSB (Most Signi) of a codeword of bits
(fixant Bit) is a flag bit. That is, the flag bit "0" indicates that the code word is the call number signal A, and the flag bit "1" indicates that the code word is one of the message code words M0-Mn (FIG. 2B, FIG. 2 (c) and FIG. 2 (d)).
Each of the code words of the signals A and M has a check bit with a length of 11 bits added for error correction (FIGS. 2 (b), 2 (c) and 2 (d)).

In the digital selective calling signal Sa to which the receiver of the present invention is applicable, the POCSAG described above is used.
Of the 20 bits for the message of the first message code word M0 of the message signal M of the system conforming format, 4 bits from the second bit to the fifth bit are allocated to the data bit 201 corresponding to the serial number inserted by the base station, The 16 bits from the 6th bit to the 21st bit are allocated to the data bits 202 for the message addressed to the receiver (FIG. 2 (c)). Since the serial number is unnecessary for the subsequent message code words M1-Mn, the entire data bit 201 is also assigned to the message data bit 202 (FIG. 2 (d)).

Referring to FIG. 3 which is a flowchart showing a signal processing procedure leading to the detection of the reception loss, a digital selective calling signal Sa obtained by demodulating a radio frequency signal from the antenna 11 by the receiving / demodulator 12. Is supplied to the decoder 14 (step 501), and the decoder 14 checks whether the address determined by the address code included in the call number signal A in the signal Sa and its insertion frame position matches its own address stored in the address memory 13. Is detected (step 502), the decoder 14 puts the CPU 20 into an operating state and sets the calling number signal A
Is sent to the CPU 20 (step 503).

The CPU 20 is activated by the decoder 14 and sends a command to the alert signal generator 16 to generate the alert signal PA. The signal PA is composed of a pulse having a period of 1 second and a duty factor of 75% as shown in FIG. The call alert signal PA is amplified by the amplifier 18 and drives the speaker 19 to notify the receiver carrier of the call.

On the other hand, the CPU 20 stores the second to fifth bits of the message code word M0 representing the serial number of the message signal M in the buffer 23 (step 504), and sets the flags of the code words M0 to Mn. Message part except the bit and the check bit, that is, the 2nd to 21st bits (data bit 20
1 and 202) are stored in the message memory 21.
Since the serial number of the message signal received immediately before the message signal is stored in the register 22, the content stored in the register 22 is subtracted from the content stored in the buffer 23 (step 505). If the difference between them is 2 or more (YES in step 506), the CPU 20 sends a start command to the reception loss alert signal generator 17 (step 507). In response to this command, the signal generator 17 generates the alert signal FA, and this signal FA
Are amplified by the amplifier 18 and drive the speaker 19. As shown in FIG. 5, this signal FA is constituted by a pulse having a period of 200 ms and a duty factor of 50% so that it can be distinguished from the above-mentioned alert signal PA. On the other hand, if the difference detected in step 506 is 1 (N in step 506)
In the case of O), no start command is supplied from the CPU 20 to the signal generator 17. In any case, step 50
When the signal processing up to 7 is completed, the CPU 20
Is transferred to the register 22 to prepare for a check for the lack of reception of the subsequent message signal (step 508).

When this receiver is used for the first time in a paging service network accompanied by message signal serial number assignment, the serial number stored in the register 22 is set to the initial value 0. The content stored in the register 22 increases by 1 every time a message signal addressed to itself is received and reaches 15, and when the next message signal is received, the content stored in the register 22 is returned to 0. Yo CPU2
0 is programmed.

The message code words M0-Mn stored in the message memory 21 are displayed on the display 31 under the control of the CPU 20. That is, code word M0
And the other data bits 202 corresponding to the serial number, and the data bits 20 of the other message code words M1-Mn.
2 is also displayed on the display unit 31. Further, the storage content of the register 22, that is, the serial number of the message received immediately before is also displayed on the display unit 31. The latter parallel display makes it easier for the receiver carrier to recognize the occurrence of missing reception and to identify the missing message.

Referring to FIG. 6, which shows an example of the display appearing on the display unit 31, the display immediately after the message signal of the serial number "6" is received is shown in FIG. Since the serial number "1" of the message signal received immediately before is also displayed, it is understood that the reception of the four message signals from the serial numbers "2" to "5" is missing.

Referring to FIG. 7, which shows a display similar to that of FIG. 6, it is shown that the serial number of the message signal received immediately before the message signal of serial number "8" is "7". It turns out that there was no omission.

In the embodiment shown in FIG.
Reference numeral 2 denotes a nonvolatile memory, for example, an EEPROM.
Alternatively, when a non-volatile memory is not used, a memory with a backup battery is employed to hold stored data.

Although the above embodiment has been described with reference to the case where the digital selective calling signal conforms to the POCSAG standard system, the idea of the present invention is that the paging by the digital selective calling signal of other formats is not limited to the above standard system. It is obvious that the method can also be applied.

[0026]

As described above, the receiver according to the present invention automatically detects the lack of the reception of the message signal and generates an alarm, so that the recognition of the lack of the reception by the receiver can be ensured. Further, since the serial number of the message signal received immediately before can be displayed on the display unit together with the serial number of the newly received message signal, it is easy to recognize the above-mentioned reception loss and specify the missing message signal.

[Brief description of the drawings]

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

FIGS. 2A to 2D are diagrams showing signal formats of a digital selective calling signal.

FIG. 3 is a flowchart showing a procedure of signal processing leading to detection of reception loss and generation of an alarm in the embodiment of FIG. 1;

FIG. 4 is a waveform diagram of a call alert signal in the embodiment of FIG.

FIG. 5 is a reception missing alert signal in the embodiment of FIG. 1;
FIG.

FIG. 6 is a diagram showing an example of a display appearing in the case of occurrence of reception loss on the message display means of the embodiment of FIG. 1;

FIG. 7 is a diagram showing an example of a display appearing on the same message display means as in FIG. 6 when there is no reception loss.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Antenna 12 Reception / demodulator 13 Address memory 14 Decoder 16 Call alert signal generator 17 Missing reception alert signal generator 18 Amplifier 19 Speaker 20 Microprocessor (CPU) 21 Message memory 22 Register 23 Buffer 30 Display control unit 31 Message display unit

Claims (4)

(57) [Claims] 1. A receiving means for receiving, from a base station, a radio signal including a call number signal and a message signal, a receiver included in the message signal and receiving from the base station
Detecting means for detecting a serial number indicating an outgoing call sequence; first storing means for storing a first serial number; a message signal received before receiving a message signal corresponding to the first serial number second storage means for storing a second sequence number corresponding to when said first and second sequence number satisfies a predetermined condition, and a notification means for performing notification, the first and A display hand that also displays the second serial number
Radio selective calling receiver characterized by having a stage, a. 2. The apparatus according to claim 1, wherein said notifying means is means for notifying when a difference between said first serial number and said second serial number is greater than or equal to a predetermined value. 2. The radio selective call receiver according to 1. 3. The radio selective call receiver according to claim 1, wherein the notification by the notification unit and the notification of the incoming call at the time of receiving the radio signal are performed in different signal formats. 4. A means for receiving from a base station a radio frequency signal modulated by a digital selective call signal including a call number signal and a message signal; and means for demodulating the radio frequency signal into the digital selective call signal. Means for decoding the selected call signal into the call number signal and the message signal; means for selectively generating a call alert in response to the output of the decoding means; and selectively outputting the output of the decoding means. Display means for displaying a series of message signals transmitted from the base station at arbitrary time intervals; and a receiver from the base station included in the message signal.
Means for detecting a serial number indicating the order of transmission of the message, first storage means for temporarily storing the latest serial number output from the detecting means, and A second storage unit that stores a last received serial number corresponding to a message signal received immediately before a message signal at least until a point in time when a message signal to which the latest serial number belongs is received; an output of the first storage unit together with means for subtracting an output of said second memory means, and means for issuing an alarm when the output of the subtraction means is 2 or more, the most recent sequence number and the immediately preceding received sequence number from
And a means for displaying .