Radio communication terminal for optimizing transmission of messages to selective call transceivers and method therefor

• US 6,512,923 B2
• Filed: 02/03/1999
• Issued: 01/28/2003
• Est. Priority Date: 02/03/1999
• Status: Expired due to Term

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Pallas, Anthony David, Lacey, James David
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US09/243,678
• Publication Number:
  US 20020058508A1
• Time in Patent Office: 1,455 Days
• Field of Search: 455/435, 455/434, 455/433, 455/456, 455/458, 455/445
• US Class Current: 455/435.1
• CPC Class Codes: H04W 68/04 multi-step notification using statistical or historical mobility data
• CPC Class Codes: H04W 84/025 with acknowledge back capability

Abstract

A radio communication terminal operating under a frequency reuse plan for communicating to and from a SCT (116) located in any one of a plurality of communication zones (118) corresponding to the frequency reuse plan, includes: a processing system (412), and a radio transceiver (114) coupled thereto. The processing system is programmed to: (202) cause the radio transceiver to receive a registration request when transmitted from the SCT as the SCT enters a new communication zone, (204) track a history of the SCT'"'"'s whereabouts according to each registration request received from the SCT, (206) receive a message intended for the SCT, (208) cause the radio transceiver to transmit the message to the SCT, and (210) cause the radio transceiver to wait a predetermined time to receive an acknowledgement message from the SCT indicating that the message was received. If the acknowledgement message is not received, the processing system is programmed to: (212, 214) determine from the history of the SCT'"'"'s whereabouts, one or more most probable communication zones where the SCT may be located, and (216) cause the radio transceiver to re-transmit the message to the SCT at the one or more most probable communication zones.

Claims

1. In a radio communication terminal comprising a controller, a plurality of base receivers, and a plurality of base transmitters, operating under a frequency reuse plan for communicating to and from a SCT (selective call ransceiver) located in any one of a plurality of communication zones corresponding to the frequency reuse plan, a method for optimizing transmission of messages to the SCTs, comprising:

receiving a registration request from the SCT each time the SCT enters a new communication zone;

tracking a time dependent history of the SCT'"'"'s whereabouts according to each registration request received from the SCT;

receiving a message intended for the SCT;

transmitting the message to the SCT;

waiting a predetermined time to receive an acknowledgement message from the SCT indicating that the message seas received;

if the acknowledgement message is not received, determining from the history of the SCT'"'"'s whereabouts one or more most probable communication zones where the SCT may be located; and

re-transmitting the message to the SCT at the one or more most probable communication zones.

2. The method as recited in claim 1, wherein the step of tracking the history of the SCT'"'"'s whereabouts comprises the step of storing in ascending order each registration request received from the SCT, each stored-entry indicating a communication zone entered by the SCT.

3. The method as recited in claim 2, wherein the foregoing storing step comprises the steps of:

allocating a buffer in the radio communication terminal having a predetermined number of entries for storing each of the registration requests; and

discarding the least recently received registration request when a registration request is received and all the predetermined number of entries of the buffer are occupied.

4. The method as recited in claim 2, wherein the step of determining the SCT'"'"'s whereabouts comprises the step of selecting one or more communication zones according to a corresponding one or more most recently stored registration requests.

5. The method as recited in claim 1, wherein the step of tracking the history of the SCT'"'"'s whereabouts comprises the steps of:

storing each registration request received from the SCT, each stored-entry indicating a communication zone entered by the SCT; and

tracking for each registration request received and stored a corresponding number of occurrences of messages transmitted to the SCT within a corresponding communication zone.

6. The method as recited in claim 5, wherein the step of determining the SCT'"'"'s whereabouts comprises the step of selecting one or more communication zones corresponding to one or more registration requests, each registration request having a high number of occurrences of messages transmitted to the SCT within a corresponding communication zone.

7. The method as recited in claim 5, wherein the step of determining the SCT'"'"'s whereabouts comprises the steps of:

applying a probability distribution function the number of occurrences of messages transmitted to the SCT for each registration request stored; and

determining according to the probability distribution function a degree of confidence that the SCT is located in one or more most probable communication zones.

8. The method as recited in claim 1, wherein the step of tracking the history of the SCT'"'"'s whereabouts comprises the steps of:

storing each registration request received from the SCT, each stored-entry indicating a corresponding communication zone entered by the SCT;

for each registration request stored,

applying a predetermined weight;

periodically tracking at predetermined intervals a corresponding number of occurrences of messages transmitted to the SCT within the corresponding communication zone; and

decreasing the weight applied to a registration request when the corresponding number of occurrences of messages transmitted to the SCT within the corresponding communication zone is less than a predetermined threshold of occurrences.

9. The method as recited in claim 8, wherein the step of decreasing a corresponding weight of a stored registration request follows an exponentially decaying function.

10. A radio communication terminal operating under a frequency reuse plan for communicating to and from a SCT (selective call transceiver) located in any one of a plurality of communication zones corresponding to the frequency reuse plan, comprising:

a processing system for directing operation of a controller;

a base transmitter coupled to the processing system for transmitting messages to the SCT;

a base receiver coupled to the processing system for receiving messages from the SCT, wherein the processing system is programmed to;

cause the base receiver to receive a registration request when transmitted from the SCT, wherein each SCT transmission occurs as a result of the SCT entering a new communication zone;

track a time dependent history of the SCT'"'"'s whereabouts according to each registration request received from the SCT;

receive a message intended for the SCT;

cause the base transmitter to transmit the message to the SCT;

cause the base receiver to wait a predetermined time to receive an acknowledgement message from the SCT indicating that the message was received;

if the acknowledgement message is not received, determine from the history of the SCT'"'"'s whereabouts one or more most probable communication zones where the SCT may be located; and

cause the base transmitter to transmit the message to the SCT at the one or more most probable communication zones.

11. A radio communication method operating under a frequency reuse plan for communicating with a selective call transceiver located in any one of a plurality of communication zones, comprising:

receiving a registration request from the selective call transceiver each time the selective call transceiver enters a new communication zone;

tracking a time dependent history of the location of the selective call transceiver in the plurality of communication zones by storing when registration requests are received from the selective call transceiver and storing the corresponding communication zones for which the registration requests were received;

determining a communication zone where the selective call transceiver is probably located at a particular time from the time dependent history of the selective call transceiver.

12. The method of claim 11, tracking the time dependent history of the location of the selective call transceiver by storing in which communication zone the selective call transceiver is most often located at a particular time.

13. The method of claim 11, determining a communication zone where the selective call transceiver is probably located by selecting the communication zone for which the most registration requests have been received historically from the selective call transceiver for the particular time.

14. The method of claim 11, tracking the time dependent history of the location of the selective call transceiver by storing the number of communication requests from the selective call transceiver for each of the, communication zones at particular times.

15. The method of claim 14, determining a communication zone where the selective call transceiver is probably located by selecting the communication zone for which the most registration requests were received historically from the selective call transceiver at the particular time.

16. The method of claim 11, determining a communication zone where the selective call transceiver is probably located by applying a probability distribution function to a number of occurrences of messages transmitted to the selective call transceiver for each registration request stored, and determining according to the probability distribution function a degree of confidence that the selective call transceiver is located in one or more most probable communication zones.

17. The method of claim 11,

transmitting a message to the selective call transceiver in the last known communication zone of the selective call transceiver, without transmitting the message to other communication zones,

if an acknowledgement is not received within a predetermined time from the selective call transceiver in response to the message transmitted, determining a communication zone where the selective call transceiver is probably located at a particular time from the time dependent history of the selective call transceiver, and

re-transmitting the message to the selective call transceiver at the communication zone identified, without transmitting the message to the other communication zones.

18. A radio communication method, comprising:

receiving a registration request from a mobile wireless communication device each time the mobile wireless communication enters one of a plurality of communication zones;

tracking a time dependent history of a plurality of registration requests of the mobile wireless communication in the plurality of communication zones;

determining a communication zone where the mobile wireless communication is probably located at a particular time from the time dependent history of the plurality of registration requests tracked.

19. The method of claim 18, tracking the time dependent history of the registration requests of the mobile wireless communication in the plurality of communication zones by storing when each of the plurality of registration requests is received and storing the communication zone for which the corresponding registration request is received.

20. The method of claim 18, paging the mobile wireless communication by transmitting a message to the mobile wireless communication at the communication zone where the mobile wireless communication is probably located.