Protocol assisted switched diversity of antennas

• US 20030096617A1
• Filed: 11/20/2001
• Published: 05/22/2003
• Est. Priority Date: 11/20/2001
• Status: Active Grant

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Miller ll, Robert Raymond, Sherman, Matthew J.
• Granted Patent: US 8,090,381 B2
• Time in Patent Office: Days
• US Class Current: 455/452.1
• CPC Class Codes: H04B 7/0822 according to predefined selection scheme
• CPC Class Codes: H04L 1/0618 Space-time coding
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence

Abstract

Fading is countered in a WLAN or similar system to maintain QoS by a fusion of switched diversity and protocol based redundancy using time spaced transmission bursts to improve the performance of radio receivers. This redundancy may be enhanced by an overlay of space-time coding of the transmission bursts.

Claims

1. A radio receiver comprising

first and second antennas connected to RF processing circuitry by an RF switch;

an RF switch control switched incrementally in response to a sequence of scheduled packet bursts.

2. The radio receiver of claim 1, wherein:

the RF switch control schedules sequence bursts prescribed by a QoS defined by a MAC protocol.

3. The radio receiver of claim 2, wherein:

a MAC processor is synchronized with transmission of a base station.

4. The radio receiver of claim 1, wherein:

the antennas are switched so that each antenna receives a related packet burst.

5. A method of maintaining a controlled QoS in a wireless communication system, comprising steps of:

receiving communications from a transceiver at a transmission station by wireless transceivers at receiving stations having switched protocol diversity reception operational modes;

communications being formatted as multiple packet bursts;

enabling a first antenna to receive a first packet burst;

enabling a second antenna to receive a second packet burst;

recording the received bursts as soft information in a storage medium;

combining the soft information from the first and second bursts into a single message.

6. The method of claim 5 wherein:

each packet burst contains a same complete message.

7. The method of claim 5 wherein:

each packet burst contains a portion of a space-time coded message spread across the first and second packet bursts.

8. A method of achieving a QoS control in a wireless LAN communication system, comprising steps of:

transmitting a message contained within a plurality of packet bursts occurring at spaced time intervals;

receiving the packet burst individually at a plurality of antennas.

9. The method of claim 8 wherein;

each of the plurality of the antennas is connected to a radio receiver at separate times relative to other receiving antennas.

10. The method of claim 8, wherein:

including a complete message within each packet burst.

11. The method of claim 8 wherein:

a message is spread across the plurality of packet bursts by space-time coding.

12. The method of claim 8 wherein:

the process of signal transmitting combines a protocol with signal processing.

19. The method of claim 8, including a further step of:

notifying a transmitter at a transmitting end by a receiving end of the number of antennas and radio receivers at the receiving end.

20. The method of claim 8, including a further step of:

a receiver notifying a transmitter that it accepts and responds to protocol-assisted diversity operations.

21. The method of claim 8, including a further step of:

upon reconstruction of a received message sending a message to the transmitting end to cease further message bursts.

13. A communication system for coupling a transmitter and a receiver adapted for receiving at least first and second signal bursts by first and second antennas respectively, and responding to the two signal bursts to communicate a single unified message at the receiver;

whereby;

the first and second signal bursts are sequentially separated in time;

the first and second antennas are sequentially enabled to communicate to storage at the receiver;

enabling a representation of the unified message by responding to the first and second signals.

14. The communication system of claim 13, wherein:

the first and second signal bursts are identical packets of a common message.

15. The communication system of claim 13, wherein:

the first and second signal bursts are each a part of a space-time coded message spread across two bursts; and

a common message is derived from the sequential signal bursts received by the first and second antennas.

16. The communication system of claim 13, wherein:

enabling includes retaining the first and second signal bursts in a storage medium and processing to deliver the single unified message.

17. The communication system of claim 13, wherein:

deriving the common message includes selecting a message from one of the receiving antennas.

18. The communication system of claim 13, wherein:

deriving the common message includes decoding a space-time coded signal spread across and received by both the first and second antennas.