Selective calling system and selective calling receiver

• US 6,310,558 B1
• Filed: 07/13/1995
• Issued: 10/30/2001
• Est. Priority Date: 07/15/1994
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Minami, Yoichiro
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Beaulieu, Yonel
• Application Number:
  US08/502,253
• Time in Patent Office: 2,301 Days
• Field of Search: 340/825.52, 340/825.44, 340/825.2, 340/825.21, 340/825.47, 370/82, 370/101.1, 370/105.1, 370/347-349
• US Class Current: 340/9.13
• CPC Class Codes: H04W 88/026 using digital address codes
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A transmission signal frame format includes an address field and a message field. The address field includes a plurality of addresses associated with the subscriber'"'"'s receivers to be called, respectively. The message field includes a plurality of messages corresponding to the addresses, respectively. A message includes a transmitting sequence number which is coincident with the transmitting order of the address corresponding to this message. A selective calling receiver, receiving a frame, sequentially searches the address field for the ID address of its own while incrementing a receiving sequence count at each the address. When the ID address is found, the receiver stores the receiving sequence count at that time. The receiver selects its own message data from the message field when the transmitting sequence number of a message is coincident with the receiving sequence count.

Claims

1. A method for transmitting data from a transmitter to a plurality of receivers, the method comprising the steps of:

at the transmitter,

(a) transmitting first signals each having a first time period which is divided into a plurality of frames,

each of the frames comprising;

a synchronization field;

an address field comprising a plurality of addresses associated with the receivers, respectively; and

a message field comprising a plurality of messages corresponding to the addresses, respectively, each of the messages comprising a message and a message header which includes an address transmission number of an address corresponding to the message, said address transmission number indicating a transmission order of each of the addresses within said address field, and

at each of the receivers,

(b) receiving a frame of at least one of the first signals;

(c) sequentially searching the address field for an address of the receiver itself while incrementing an address count at each address searched;

(d) storing the address count when the address of the receiver itself is found; and

(e) selecting a message addressed to the receiver itself from the message field by comparing the address count stored with the address transmission number included in the message header.

2. The method according to claim 1, wherein the address field is terminated by a predetermined word.

3. The method according to claim 2, further comprising the steps of:

terminating the step (c) when the predetermined word is found; and

returning to the step (b).

4. The method according to claim 1, wherein the message header comprises:

a first field for containing a message header indicator;

a second field for containing the adress transmission number;

a third field for containing a message type; and

a fourth field for containing a message length.

5. The method according to claim 4, wherein the step (e) comprises:

detecting a message header from the message field;

comparing the address count stored with the address transmission number included in the message header; and

selecting the message addressed to the receiver itself when the address count stored is coincident with the address transmission number in accordance with the message type and the message length.

6. The method according to claim 2, wherein the message header comprises:

a first field for containing a message header indicator;

a second field for containing the adress transmission number;

a third field for containing a message type; and

a fourth field for containing a message length.

7. The method according to claim 6, further comprising the steps of:

terminating the step (c) when the predetermined word is found; and

returning to the step (b).

8. The method according to claim 6, wherein the step (e) comprises:

detecting a message header from the message field;

comparing the address count stored with the address transmission number included in the message header; and

selecting the message addressed to the receiver itself when the address count stored is coincident with the address transmission number in accordance with the message type and the message length.

9. A transmitting method for transmitting data from a transmitter to a plurality of receivers, the method comprising the steps of:

(a) dividing a predetermined time period into a plurality of frames,

in each of the frames

(b) generating a synchronization signal;

(c) sequentially generating a plurality of address signals associated with the receivers, respectively;

(d) storing an address transmission count which is incremented at each address signal;

(e) sequentially generating a plurality of message signals corresponding to the address signals, respectively, each of the message signals comprising a message and a message header which includes the address transmission count of an address signal corresponding to the message signal, said address transmission count indicating a transmission order of each of the addresses within said address field; and

(f) transmitting the frames to the receivers.

10. The method according to claim 9, wherein the address signals is terminated by a predetermined word.

11. The method according to claim 9, wherein the message header comprises:

a first field for containing a message header indicator;

a second field for containing the adress transmission count;

a third field for containing a message type; and

a fourth field for containing a message length.

12. A receiver comprising:

receiving means for receiving a frame of at least a first signal, said frame comprising a synchronization field, an address field comprising a plurality of addresses associated with the receivers, respectively, and a message field comprising a plurality of messages corresponding to the addresses, respectively, each of the messages comprising a message and a message header which includes an address transmission number of an address corresponding to the message, said address transmission number indicating a transmission order of each of the addresses within said address field;

searching means for sequentially searching the address field for an address of the receiver itself while incrementing an address count at each address searched;

storage means for storing the address count when the address of the receiver itself is found; and

message selecting means for selecting a message addressed to the receiver itself from the message field by comparing the address count stored with the address transmission number included in the message header.

13. The receiver according to claim 12, wherein the address field is terminated by a predetermined word.

14. The receiver according to claim 13, wherein the searching means stops searching the address field when the predetermined word is found.

15. The receiver according to claim 12, wherein the message header comprises:

a first field for containing a message header indicator;

a second field for containing the adress transmission number;

a third field for containing a message type; and

a fourth field for containing a message length.

16. The receiver according to claim 15, wherein the message selecting means comprises:

header detecting means for detecting a message header from the message field;

comparing means for comparing the address count stored with the address transmission number included in the message header; and

selecting means for selecting the message addressed to the receiver itself when the address count stored in coincident with the address transmission number in accordance with the message type and the message length.

17. A selective calling receiver comprising:

receiving means for intermittently receiving a first signal comprising a plurality of frames, each of the frames comprising an address field of addresses and a message field of messages, the respective addresses being associated with the messages, each of the messages including an address transmission number, said address transmission number indicating a transmission order of each of the addresses within said address field;

searching means for sequentially searching the address field for an address of the selective calling receiver itself while incrementing an address count at each address searched;

storage means for storing the address count when the address of the selective calling receiver itself is found; and

message selecting means for selecting a message addressed to the selective calling receiver itself from the message field by comparing the address count stored with the address transmission number.

18. The selective calling receiver according to claim 17, wherein the address field is terminated by a predetermined word.

19. The selective calling receiver according to claim 18, wherein the searching means stops searching the address field when the predetermined word is found.

20. The selective calling receiver according to claim 17, wherein each the message comprises a message header and message data, the message header comprising:

a first field for containing a message header indicator;

a second field for containing the adress transmission number;

a third field for containing a message type; and

a fourth field for containing a message length.

21. The selective calling receiver according to claim 20, wherein the message selecting means comprises:

header detecting means for detecting a message header from the message field;

comparing means for comparing the address count stored with the address transmission number included in the message header; and

selecting means for selecting the message data addressed to the selective calling receiver itself when the address count stored in coincident with the address transmission number in accordance with the message type and the message length.

27. The selective calling receiver according to claim 17, further comprising:

a battery as a power supply of the selective calling receiver; and

power control means for controlling the battery such that power is supplied to at least the receiving means in accordance with intermittent timing of receiving a frame of the first signal.

22. A receiving method for receiving a first signal comprising a plurality of frames, each of the frames comprising an address field of addresses and a message field of messages, the addresses being associated with the messages, respectively, and each of the messages including an address transmission number, said adress transmission number indicating a transmission order of each of the addresses within said address field, the receiving method comprising the steps of:

(a) sequentially searching the address field for a specific address indicating a relevant receiver while incrementing an address count at each address searched;

(b) storing the address count when the specific address is found; and

(c) selecting a specific message addressed to the relevant receiver from the message field by comparing the address count stored with the address transmission number.

23. The receiving method according to claim 22, wherein the address field is terminated by a predetermined word.

24. The receiving method according to claim 23, further comprising the step of:

terminating the step (a) when the predetermined word is found.

25. The receiving method according to claim 22, wherein each the message comprises a message header and message data, the message header comprising:

a first field for containing a message header indicator;

a second field for containing the adress transmission number;

a third field for containing a message type; and

a fourth field for containing a message length.

26. The method according to claim 25, wherein the step (c) comprises the steps of:

detecting a message header from the message field;

comparing the address count stored with the address transmission number included in the message header; and

selecting the message data addressed to the relevant receiver when the address count stored is coincident with the address transmission number in accordance with the message type and the message length.