JP2821228B2 - Radio selective calling communication device - Google Patents

Abstract

PURPOSE:To transmit the information from a base station just once and to attain the effective use of a radio wave by setting an information reception control state (a receiver kept in a BS-III mode). CONSTITUTION:If a received signal is identical with 'address code words', the signal is compared with an internal No pager ID of a ROM 5 (call No recording part). When the coincidence is secured in the comparison, the address name of the pager ID is sent to a CPU 6. Then the CPU 6 checks the state of each pager ID, i.e., the propriety of reception of a part of a RAM 7 (message recording part). If the reception is inhibited for the pager ID, the CPU 6 order an SW 11 (power supply control part battery saving circuit) to secure a battery saving modr I. Then the SW 11 is set in a mode in which the power supply control is repeated to a DEC 4. Thus the information are transmitted in a single time from a base station. Then the availability of a radio wave is improved.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information receiver in an individual selective call receiver with a character display function, and in particular, a numeral display type receiver using a POCSAG system for Code Format. (Numeric Display Pager)
Or, a character display type receiver (Alpha-numeric Display Pag
er).

[Prior Art] The POCSAG system, which is a type of paging calling system, is a revolutionary system that can send not only individual selective calling but also numeric information or character information after calling.

[Problem to be Solved by the Invention] The conventional POCSAG method described above is very effective for a system mainly performing individual selection calling.

That is, character information to be transmitted continuously after the individual selective calling is performed is sent out. However, when the same information is specified to a large number of subscribers, even if the calling numbers of the subscribers to receive the information are unified to a certain extent, the information can be divided into a maximum of 8 groups. If the subscribers are dispersed in all the groups, the subscriber number for calling and the information to be notified are repeated eight times.

Or, if the call numbers are unified and all come to the same Group, individual call numbers are set every eight,
The maximum subscription capacity of the POCSAG system is 1/8, and POCSAG
Group of unassigned in Signal Format of method
Frame has the drawback that the Idle Code Word is sent and the efficiency of radio waves is reduced.

[Means for Solving the Problems] A communication apparatus of the present invention has a base station and a plurality of receivers, sets a plurality of unique call numbers for each receiver, and sets a predetermined call number among the call numbers. Means for detecting that a call has been received with more than a number of call numbers, means for capturing character display information sent from the base station with a certain regularity according to the regularity, and means for capturing the captured character display information. A means for storing the information on the ground information storage unit, a calling means, and a means for displaying on the display unit each time. When the base station causes a plurality of receivers to receive the same character display information, each reception is performed. Each receiver is individually called with a call number equal to or greater than the predetermined number of the receivers. Therefore, even if there is a time lag from when the call is received to when the character display information is sent, there is no problem.

With this function, the same information should be sent, even if the subscribers are divided into several groups, if all the subscribers are called sequentially and controlled to catch according to the regularity as described above, then You only need to send the information once.

Example Next, the present invention will be described with reference to the drawings.

1. FIG. 1 is a basic configuration diagram of the receiver of the present invention.

The signal (radio wave) sent from the base is received by ANT1 (antenna) and demodulated by RX2 (FM receiver). DISC3
The output signal of the (discrete circuit) is a digital signal, which is decoded by the decoder unit 4. If the transmitted signal is “Address Codewords”, it is stored in ROM5 (call number recording unit), ie, the recorded Page
r Compare with ID. Here, multiple Pager IDs are recorded, and if any of these matches,
The address name of the ID is sent to the CPU 6 (central processing unit). CPU
6 collates the status of each Pager ID in a part of the RAM 7 (message storage unit), that is, whether reception is possible (Receive / Inhibit), according to the address of the sent Pager ID.

(Whether or not reception is possible will be described in Section 6 below.) If Pager is prohibited from receiving (Inhibit)
If the ID is the ID, the CPU 6 switches SW11 (power supply control unit Battery S
aving circuit) and Battery Saving mode I. (BS-I
Mode: Detailed description will be given in 3 below. ).

With this command, SW11 controls power supply to RX2 and DEC4, that is, enters a mode in which "OFF" / "ON" is repeated.

If the reception is possible (Receive), the transmission information transmitted continuously is received. The received information is “Address”
And “Multi Function” are added and stored in RAM7 (message storage unit), and at the same time, DRV9 (display unit drive unit)
And displayed on the DISP10 (display unit). At the same time, a ringing tone is emitted from the 8P13 (speaker).

The above is an explanation of the operation of the receiver according to the present invention as an individual selective calling device, which is a basic operation.

Here, for the sake of convenience, this receiver is described below in 13; Batteryu Sa
Batteryu Saving Mode II (B
(S-II mode) That is, the description has been made assuming that the Address Code words can be received.

2. Description of POSAG method Next, PACSA such as POCSAG Digital Paging Signal Format
The G method will be described.

2,1 Signal Format As shown in FIG. 2, the Signal Format of the POCSAG system includes two parts: a) Preamble and b) Batch Structure.

a) Preamble is a signal sent for bit synchronization of a receiver (individually selected paging receiver; also referred to as pager).

b) Batch Structure is SC; Synchronization Codeword
Starting with 1 codeword of the synchronization signal called "FRAME", 8 FRAMEs consisting of 2 Codewords are continued. 17 in total
Codewords. This Batch Structure continues until there are no more calls.

2,2 Types of Codewords 1Codeword consists of 32 bits. There are the following four types of code words.

a) Synchronization Codeword b) Address Codeword c) Message Codeword d) Idle Codeword Next, the contents of each Codeword are shown in FIG.

 FIG. 3-1 shows a) Synchronization Codeword.

Figure 3-2 shows b) Address Codeword and c) Message Co
Indicates the deword structure. Bit Number1 (1st Bi
t) is “0” when Address Codeword is (also referred to as Message Flag), and is “1” when it is Message Codeword. With this, Codeword sent from the base is AddressC
odeword or Message Codeword can be determined. This Messa
After the ge Flag, in the case of Address Codeword, Address
bits is 18 bits, Function bits is 2 bits, and then Par
ity check bits is 10 bits, and Even Parity is 1 bit
This ends one Codeword of 32 bits in total.

In addition, Message Codeword follows Message Flage,
Parity check bits are 10 bits, and Even Parit is the same as when essage bits are 20 bits and then Address Codeword.
y is 1 bit, which forms 1 Codeword of 32 bits in total.

FIG. 3-3 shows the idle codeword. This is Address C
Used when there is no odeword or Message Codeword. 2, 3 calling number (Page Identities) The calling number unique to the receiver is formed by 7 digits. The configuration is shown in FIG. 7 digit calling number (7Digits Identity)
Has a 21-bit configuration if it is represented in binary (Binary Conversion). Bits Number 19, 20, and 21 are the location of the Frame, that is, what frame (the transmission frame)
The remaining 18 bits will be determined by Address Codewo
Send by rd.

It should be noted that the 20th and 21st addresses in the Address Codeword (♯
20, 21) Function bits determine four ring tones (identities of A, B, C and D).

FIG. 5 shows the relationship between Function bits and Multi Function. The remaining 22nd to 31st 10 bits are formed from the 1st to 21st bits.
Check bits. The last 32nd is the Even Parity for the 1st to 31st bits.

2,4 Numeric Data Coding Method Numeric Data Coding Method
Will be described below. This method is 4bits and the numbers 0-9
And hyphen, emergency mark: Urgency Symbo
l “U”, left parenthesis, right parenthesis, special symbol: * mark and space are displayed.

This relationship is a Character Set based on Binary Coded Decimal (BCD) code, and is shown in FIG.

Next, FIG. 7 shows an example in which data is transmitted using this Character Set in a numeric display code system. In this example, the call number (page ID) unique to the receiver belongs to Group2. The transmission information (Data) is “01234567”.

To transmit 8 characters (8 characters) of this Data, 8 char
acters x 4 bits / character = 32 bits required, 1 Messa
ge Codewors is 20 × 2 because Message Bits is 20
= 40> 32, two Message Codewords are required.

Note that in this case, 40-32 = 8 bits of Message bits are left over, but the surplus will be transmitted with Space.

2,5 α-Numeric Data Coding Method Alpha-Numeric Data Coding Method
ding Method) is described below. This method uses 7bits
To display English letters, numbers and various symbols. This character string (character Set) is shown in FIG.
Uses the it coded character set. (ISO 646
Next, using this code, Data which is character display information
9 is shown in FIG. In this example, the call number (Page ID) unique to the receiver belongs to Group 2. The transmission information (Data) is “ABCDEfghi”. To transmit 10 characters (10characters) of this Data, 10characters × 7bits /
characters = 70bits is required and 1 Message Codeword is
Since Message Bits is 20, from 20 × 4 = 80> 70, Me
You need 4 ssage Codewords. In this case, 8
0-70 = 10 bits of extra Message bits, but this extra is sent by sending special character “EOT” to Codewor.
Form d.

Furthermore, the Message Data to be transmitted is large and one Ba
If it cannot be accommodated by tch, the next batch will be used to communicate. An example is shown in FIG. In this example, the Message Data “M3” transmitted to the subscriber (receiver; Pager) having “S3”, which is the Pager ID belonging to Group 5, is 2
It spans one Batch (in the example it spans 1st Batch and 2nd Batch).

3. Battery Saving Operation The receiver of the present invention employs the Battery Saving System in order to extend the life of the power supply battery, but is classified into the following three according to the operation mode.

(1) BSI: Preamble Search Mode (2) BSII: Self Address Search Mode (3) BSIII: Message Data Search Mode Next, each mode will be described.

3,1BSI: Preamble Search Mode This is the “AF” stag with a certain synchronization as shown in 2 and 3 in FIG.
The power supply of the e and “RF” stages is turned ON / OFF repeatedly. When both “AF” stage and “RF” stage are “ON”, “P”
Search for "reamble signal". If it cannot be captured, repeat this ON / OFF. By the way, in the case of the example,
“AF” stage power supply “ON”, that is, Battery Saving
The “OFF” time is 65 msec. And the power supply “OFF”
That is, the time of Battery Saving “ON” is 997.5 msec. Furthermore, “OFF” and “ON” of Battery Saving of “RF” stage
Are 30 msec. And 1032.5 msec., Respectively.
That is, “ON” / “OFF” is repeated at a period of 1062.5 msec.

The above is Battery Saving operation (Battery Saving Operati
This is the operation of “Preamble Search Mode” which is one of the BSIs of “on). If Battery Saving “OFF” here, Preamb
If the signal can be captured, the receiver
I: Enter Self Address Search Mode.

3,2 BSII: Self Address Search Mode When the preamble signal is captured, the Battery Saving “O
FF "continues and continues until the SC (Synchronization Codeword) is confirmed. After confirming the SC, Battery Saving becomes" ON ", but the FRA of the group to which the calling number in the ROM 5 of the receiver belongs.
At the time corresponding to ME, Battery Saving “OFF”,
Power “ON” and go to search for Address Codeword. Figure
An example is shown in Fig. 12. In this example, the receiver (Pager) is Gro
belongs to up 6.

Consider the first Codeword in Frame 5, if this is Add
Even if it is a ress Codeword, the call number (Self Addr
If not, or if it is a Message Codeword, consider the next Codeword. In the example, the next Codeword is also Se
Since it is not an lf address, Battery Saving is turned “ON” again and continues until the next SC.

The above is Battery Saving operation (Battery Saving Operati
on) One of the BSIIs “Self Address Search Mo”
de "is one example.

Next, FIG. 13 shows an example of a case where the own calling number (Self Address) is captured. In this example, the second of Frame 5 is its own calling number (Self Address), and subsequently Message Data is sent. In this example, since the Address Codeword has been transmitted following the Message Data, the receiver determines that the Message Data has been completed, and here, the Battery Saving Operation: BSII
And Battery Saving “OFF” only during the period corresponding to the SC and the Frame to which it belongs.

Next, FIG. 14 will be described. This is for each Batt
This indicates that under certain conditions during ery Saving Operation, the mode is transferred to another mode. 14 in FIG. 14 is BSII: Sel.
f If the SC cannot be detected twice consecutively in the Address Search Mode, it indicates that the process returns to the BSI: Preamble Search Mode.

14 in FIG. 14 is a BSII: Self Address Search Mode. When the Self Address is captured and Message Data is received, that is, Message Data detection mode, the Address Pattern is set immediately after Message Data.
That is, when a Codeword with a Message Flag of “0” comes,
From ssage Data detection mode, BSII Self Address Se
Enter arch Mode.

Next, if the system uses the alphanumeric code (Al
If the pka-Numeric Data Coding Method) is used, the “EOT” signal is used as Dummy in order to adjust the number of bits when Data bits are completed halfway in the Message Codeword.
Insert the message data detection mode for BSII
If this "EOT" signal is detected in the
From Data detection mode, Self Address Search mode
Enter.

2,3 BSIII: Message Data Search Mode The operation of this mode will be described with reference to FIGS. First,
FIG. 15 shows that the receiver captures the Self Address in the BSII: Self Address Search Mode,
Read the word, if this is a particular special control code (hereinafter Control Codeword), then the receiver enters BSII: Message Data Search Mode. This Mode, immediately after receiving the Control Codeword,
Battery Saving becomes “ON” and continues until the next SC. S
Battery Saving “OFF” when C comes, confirm SC, Codeword immediately after, that is, the first Code of 1st Group
Consider whether word is Message Codeword. If Me
If not ssage Codeword, Battery Saving as shown
Turns “ON”. And it continues until the next SC comes. When the SC comes again, Battery Saving is turned “OFF”, and the operation of checking the SC and examining the type of the first Codeword of the first group is repeated. Here, the first Group
If the first Codeword of is a Message Codeword, Ba
ttery Saving keeps “OFF”. This state is shown in FIG.

FIG. 16 shows a state in which Message Data is read, and when the following two conditions are satisfied, another Battery Sa is read.
The transition to the ving Operation Mode will be described.

First, FIG. 16A shows that when SC cannot be captured twice consecutively, the Battery Saving Operation starts in BSI Mode,
That is, the process returns to the preamble search mode.

FIG. 16-2 shows that while capturing Message Data, the Address
When Codeword comes, Battery Saving Operation is BS
Return to II Mode, that is, Self Address Search Mode.

Note that in FIG. 15 above, the Message Data Search Mo
Even if it is de, Battery Saving is set to “OFF” only when the Frame of the Group to which it belongs comes, and here again,
Address Codeword or Message Codeword, or C
If the Mode to search for ontrol Codeword is specially added, this is the normal BSIII: Message Data Search described above.
Mode and BSIII-1: Message Data and Self
It is called Address Search Mode.

Further, in FIG. 15 described above, the receiver is BSII: Self Ad
In the Dress Search Mode, the BS only captures the Self Address, that is, without capturing the specific special control code (Control Codeword) immediately after the Self Address.
III: It can be considered under conditions that may enter Message Data Search Mode. In order to distinguish this from the above-mentioned ordinary BSIII, BSIII-2: Message Data Search Directly Mo
Call it de.

4. Description of the operation of the information receiver The character display type individual selective call receiver usually determines which call number out of a plurality of call numbers of the receiver together with the received information, The function bits at that time are stored in the RAM 7, which is an information storage unit, together with additional information such as something, and this is performed in the order of reception.

And when information exceeding the storage capacity is sent,
Old information is erased. This will be described with reference to FIG.

First, FIG. 17A shows that information 4 has been received in a state where information 1, 2, and 3 are already stored in the RAM of the receiver. The result is the left part of FIG. 17-2. Next, information 5 is received. The result is shown in Figure 17-
3 is the left part. Here, the storage capacity of the RAM is “FULL”
That is, it indicates that it is full. In addition, FIG. 17 shows what happens when information: 6 is received.
-4. That is, new information from the left side of RAM: 6
, The old information is pushed to the right.

As a result, information 1 and 2 completely protrude. Also information:
Some parts of 3 are protruding. Information that exceeds the storage capacity by a small amount is erased. That is, information: 3 is also an object of erasure. As a result, the contents of RAM are as shown in Fig. 17-5.
It becomes as shown in. Here, an empty space may occur at the right end.

 Next, a function called an information receiver will be described.

The normal individual call as described above is to separately allocate a part of the information storage unit for the information receiver function in advance.

That is, a specific call number (or a specific Function Bit) among a plurality of call numbers possessed by the receiver
), A specific information storage unit is allocated in advance, and is made independent of a storage unit for information called and sent by another call number.

If the receiver has a plurality of specific call numbers having this independent information storage unit, a role is determined for each call number, so that, for example, information on stocks,
It can be used as a receiver for a system that broadcasts information that changes every moment, such as the price of gold and other precious metals, the exchange rate, and the commodity exchange rate. This may be called an information receiver. The feature of this information receiver is that, since an independent information storage unit is assigned, information called and received by a specific call number is stored in the storage unit and simultaneously stored in the old storage unit. The information is to be deleted automatically. That is, the information is automatically updated. Further, in this case, one of the features is that the information stored in the other area of the information storage unit is not affected at all.

The operation of the information receiver will be described below with reference to the drawings. First, FIG. 17-6 shows a state in which normal information 1, 2, and 3 are already stored, and information 4 and information 5 are stored in II of specific information storage units II, III, IV, and V. Is shown. Then, the information 6 was received. At this time, this information is specified information III
So there is this information: 6. The result is shown in FIG. 17-7. And furthermore, information: 7 was received. Since this information is the specific information IV, the old information: 5 in the specific information storage unit IV is expelled and deleted. There is new information: 7 in it. This is shown in Figure 17-8.

5. The receiver of the present invention has a plurality of unique call numbers.

These are recorded in the ROM 5 (call number recording unit).

For example, $ 1 ... 0001001 $ 2 ... 0002001 $ 3 ... 0300001 $ 4 ... 0004001 $ 5 ... 0005001 Here, a predetermined number or more of call numbers (for example, 0200000)
As described above, when a call is received, the receiver immediately switches from the BS-II mode (Self Address Search Mode) to the BS-II mode.
Enter I mode (Message Data Search Mode). (However, in the present invention, this means the BS-III-2 mode of the BS-III modes described in the above 3. The same applies hereinafter.)
It is ready to receive the transmitted information.

The certain regularity of the information transmitted from the base is
Specifically, after the second Batch (Second & Sub-sequent
Batch) immediately after SC (Synchronization Codeword), that is, 1st Codeword of 1st Frame (Fo) of the Batch
Is to send the transmission information by Message Codeword.

The receiver of the present invention waits for an information signal in the BS-III mode. After SC, Address Codeword or
When the Idle Codeword (both Message Flag is “0”) arrives, the BS- Battery Saving Operation is immediately executed.
Enter III mode. This is, immediately after SC, Message Cod
The eword, that is, the message flag continues until “1” comes.

This operation has an advantage in that all the individually selected paging receivers that want to send the same information can be prepared to receive information under the same conditions regardless of the Group (1 to 8) to which each Pager belongs. This is useful in the information receiver system of item 4 above. The information reception is to send the same information to a subscriber who satisfies specific conditions (payment fee, etc.) for information such as stocks and exchanges. For example, subscribers satisfying certain conditions are assigned the following numbers:

0300001,0300002,0300003,0300004,0300005,0300006,
Since eight numbers 0300007 and 0300008 are assigned, all subscribers always belong to any one of the groups, and therefore use any one of the above.

In the present invention, one of these is called RO
It is recorded in M5 (call number recording section). When a call is received, it is determined whether the call number is equal to or greater than a predetermined number (020000 in the example set above). If a call is received by any one of the above eight numbers, this condition (greater than the set value of 020000) is satisfied, so that the BS-III mode is automatically entered. First, the subscriber number (call number) of GROUP 1 is sent from the base station. That is, “0300001” is sent. Also, GROUP 2 subscribers will receive `` 030000
Send 2 ". Similarly, call number “030000” up to GROUP8
3 ”to“ 0300008 ”. The receivers belonging to all groups are now in the BS-III mode. Here SC (Synch
ronization Codeword) immediately after the transmission information (for example, xx
Xx) only once.

With this, all the receivers simultaneously transmit information (xxxx).
×) can be received. FIG. 18A shows this state.

In the figure, “△” is a call number for a subscriber belonging to each Group, and “D” is an Idle Codeword for Dummy.

This time, since the call number was one for each Group, all calls were completed within the 1st Batch and the SC of the 2nd Batch
I was able to send the information immediately after.

6. Whether or not information can be received (reception prohibition setting) As described above, the information receiver broadcasts the same information to many subscribers. Therefore, it is necessary to take measures so that information cannot be received for an individual selective call receiver having specific conditions such as a subscriber who has not paid a fee. That is the reception prohibition process. This is done by calling each subscriber's unique calling number and then using a special control code (eg, "4").
The information for stopping the information receiving function is stored in the RAM 7 using
(Message storage unit) is added to the information reception ID and written. As a result, even if the special control code "1" is received following the call number with this ID, the mode does not shift to the BS-III mode and information cannot be received.

[Effects of the Invention] As described above, the present invention provides information reception control (BS-II
When the receiver enters I-mode), the transmission of the transmission information from the base station only needs to be performed once, so that there is an effect that radio waves can be effectively used.

For example, let's compare the occupation time of radio waves, assuming that 20 characters are sent to each Gruop subscriber using the Numeric Data Coding Method.

 First, to send 20 characters, 20 (characters) x 4 (bits / character) ÷ 20 (bits / codeword) = 4 (Codewords) 4 codewords are required.

(1) In the case of the transmission method of the present invention (the BS-III mode is used) Referring to FIG. “△” is a call number for each Group, and “D” is an Idle Codeword for Dammy.
Since the command to BS-III mode has been completed for all receivers in the first batch, the transmission information `` xxx
× ”: Send 4 codewords equivalent to 20 characters of numeric information.

1. Preamble Signal = 18 Codewords 2.1st Batch = 17 Codewords 3.2nd Batch = 5 Codewords, for a total of 40 Codewords.

Since 1 Codeword is 32 bits, 32 × 40 = 1280 bits. If the signal transmission rate (Baund Rate) is 512 (bits / se
If c.), 1280/512 = 2.5, that is, the radio wave occupation time of 2.5 seconds.

(2) In the case of the conventional ordinary transmission method: FIG. Immediately after each Pager ID (indicated by "@"), 4Codewords of transmission information: "xxx" are transmitted every time, so it takes some time in the third batch.

1. Preamble Signal = 18 Codewords 2.1st, 2nd Batch = 17 x 2 = 34 Codewords The first half of 3.3rd Batch = 14 Codewords, for a total of 66 Codewords. 32 × 66 = 2112bits, Baud
If the Rate is 5/2 (bits / sec), it takes 2112/512 = 4.125, that is, 4.125 seconds.

From the above, 66Codewords / 40Codewors = 1.65x40
/66=0.6060...about 60%, 100-60 = 40% By using the information reception control (BS-III mode), in this example, the radio wave occupation time was reduced by about 40%. The effect will be more pronounced if this is longer and longer information.

[Brief description of the drawings]

FIG. 1 is a block diagram of an individual selective calling receiver with a character display function of the present invention, and FIG. 2 is a signal configuration (Signal F) of the POCSAG system.
or-mat), Fig. 3 is the structure of Codeword, 3-1
The figure shows the Synchronization Codeword, and Fig. 3-2 shows the Code
word Structure, Fig. 3-3, Idle Codeword, Fig. 4
The figure shows the page identity, that is, the structure of the called number, fifth.
The figure shows the relationship between Function Bits and Multi Function, and FIG. 6 shows the figure display code system (Numeric
FIG. 7 is a diagram showing an example of signal transmission in the case of a numeric display code system (Numeric Message Form).
at), FIG. 8 is a diagram showing an alphanumeric data display code system (Alpha-Numeric Data Coding Method), and FIG.
FIG. 10 shows an example of signal transmission in the case of the alphanumeric display code system (Alpha-Numeric Message Format), and FIG. 10 shows an example of signal transmission in the case of the alphanumeric display code system (Alpha-Numeric Message Format). Format example), Fig. 11 is B
attery Saving Operation Preamble Search Mode (BS
-I mode), FIG. 11-1 is a transmission signal from the base station, FIG. 11-2 is a diagram showing the power control status of the "AF" stage of the receiver, FIG. 11-3, FIG. 12 shows the power control status of the “RF” stage of the receiver. FIG. 12 shows that the receiver belonging to Group “6” captures the pre-amble signal and
Entering ch Mode (BS-II mode), SC shows that BatterySaving is “OFF” at Frame 5 (F5), which is Group “6”. FIG. 13 shows Group “6”. And FIG. 14 shows that the receiver belonging to (1) has detected the Message Data and then returned to the BS-II mode. FIG. 14 is a diagram showing the movement of the receiver in the BS-II mode. The figure shows that if the SC cannot be detected twice consecutively, the mode returns to the BS-I mode.
ode, that is, while receiving the transmission information, the next Address Pater
n, that is, when a message with a Message Flag of “0” is received, the mode returns to the BS-II mode again. FIG. 14-3 also shows a case where a special code “EOT” code is set in the Message Data Detection Mode. FIG. 15 is a diagram showing returning to the BS-II mode when received, and FIG.
Indicates the BS-III mode called Message Data Search Mode. That is, when a certain condition is satisfied, the information immediately after the SC (Message Flag is “1”) is searched. Prea
Preamble Search Mode (B
In the S-I mode), when the preamble signal is captured, Seflf
It becomes Address Search Mode (BS-II mode). Then sel
f When the Address and special control code are captured, Message Dat
a Indicates that you are in Search Mode (BS-III mode).
FIG. 16 shows the case where the SC is not received twice in the BS-III mode or the next Address P in the Message Data Detection Mode.
atern is received or special code "EOT" code
FIG. 17 is a diagram illustrating the operation of the information receiver when FIG. 17 is received. FIGS. 17-1 to 17-5 show examples of the case of a normal individual selection call receiver. And 17-
Figures 6 to 17-8 show the unique behavior of the information receiver, FIG.
The figure shows a comparison between normal transmission and transmission using the special control code of the present invention. ANT1: Antenna (antenna), RX2: FM receiver, DISC3: Discrete circuit, DEC4: Decoder, ROM5: Read-only memory (call number recording unit), CPU6: Central processing unit, RAM7: Write / read memory at any time (information Storage unit), DRV9: display drive unit, DISP10: display unit, SW11: power supply control unit (Battery Sa)
ving Circuit), PS12: power supply, SP13: speaker.

Claims (1)

(57) [Claims] 1. A base station and a plurality of receivers, a plurality of unique call numbers are set for each receiver, and a call is received with a predetermined number or more of the call numbers among the call numbers. Means for detecting that the character display information is sent from the base station with a certain regularity in accordance with the regularity, and means for storing the captured character display information in the grounding information storage unit one by one. And calling means, and means for displaying on a display unit, when the base station causes a plurality of receivers to receive the same character display information, the predetermined number or more of the respective receivers A radio selective call communication device, wherein each receiver is individually called by a call number.