Method and system for half-duplex wireless communication

• US 6,370,123 B1
• Filed: 01/21/1998
• Issued: 04/09/2002
• Est. Priority Date: 01/21/1998
• Status: Expired due to Term

• Current Assignee: RPX Corporation
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Woo, Thomas Yat Chung
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Pezzlo, John
• Application Number:
  US09/010,076
• Time in Patent Office: 1,539 Days
• Field of Search: 370/229, 370/236, 370/346, 370/347, 370/349, 370/445, 370/462, 370/311, 370/278, 455/524, 455/422, 725/81, 375/220, 375/222
• US Class Current: 370/278
• CPC Class Codes: H04W 74/0816 with collision avoidance
• CPC Class Codes: H04W 74/085 collision avoidance

Abstract

The present invention is a method and system of half-duplex wireless communication where a premises has a base station that services a defined communication cell. The base station transmits and receives Request to Send and Clear to Send announcements to and from mobile stations to indicate that the base station can send and receive data. A plurality of mobile stations send and receive data after transmitting and receiving Clear to Send and Request to Send announcements to and from the base station based on the respective time period in which the base station has received the Clear to Send and Request to Send announcements from respective mobile stations.

Claims

1. A method of half-duplex wireless communication comprising the steps of:

transmitting from a base station to a plurality of mobile stations contained within one wireless communication cell that is serviced by the base station a Ready announcement indicating that the base station is ready to receive data on an uplink channel from the mobile stations,

setting a random initial backoff time for each mobile station and transmitting from each mobile station a Request to Send announcement to the base station following expiration of the backoff time,

transmitting from the base station to the mobile stations a Clear to Send announcement indicating that the first mobile station to have had its Request to Send announcement received in the base station can now transmit data,

resubmitting the Request to Send announcements from the other mobile stations after a predetermined backoff time period has expired corresponding to a time period in which the first mobile station can transmit its data to the base station, and

prioritizing any messages from the mobile stations by setting a higher probability that the base station will be in a receiving state rather than a transmitting state.

2. The method according to claim 1 including the steps of transmitting Clear to Send announcements from the mobile stations to the base station indicating that mobile stations are clear to receive data from the base station, and transmitting the data from the base station to a respective mobile station based on the first Clear to Send announcement received within the base station.

3. A half-duplex wireless communication system comprising a premises having a base station that services a defined communication cell, wherein the base station transmits and receives Request to Send and Clear to Send announcements to and from mobile stations to indicate that the base station can receive and send data, and a plurality of mobile stations that send and receive data after transmitting and receiving Clear to Send and Request to Send announcements to and from the base station based on the respective time period in which the base station has received the Clear to Send and Request to Send announcements from respective mobile stations, and means for prioritizing any messages from the mobile stations by setting a higher probability that a base station will be in a receiving state rather than a transmitting state.

4. The system according to claim 3 wherein a Request to Send and Clear to Send announcement exchange must occur between the base station and mobile station before any data exchange can occur.

5. The system according to claim 3 wherein the base station and a mobile station send and receive an acknowledgement message signalling the completion of data transfer.