Acknowledging missed messages broadcast on a control channel

• US 20030119557A1
• Filed: 12/20/2001
• Published: 06/26/2003
• Est. Priority Date: 12/20/2001
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Lundby, Stein A.
• Granted Patent: US 6,993,352 B2
• Time in Patent Office: Days
• US Class Current: 455/561
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1858 Transmission or retransmission of more than one copy of acknowledgement message

Abstract

Methods and apparatus are presented for acknowledging missed control channel messages. In a system wherein control channel messages can be used to send the transmission parameters of signals on a data traffic channel, the inability to decode the latest control channel message can cause a delay in system throughput. Functionality is added to the acknowledgment channel, which is already in place to acknowledge the receipt of data subpackets on the data traffic channel, so that acknowledgments of missed control channel messages can be conveyed. A pattern or multiplicity of acknowledgment signals can be used to request transmissions of control channel messages. An infrastructure element can be configured to read the acknowledgment signals as a request for a broadcast on the control channel.

Claims

1. In a wireless communication system, apparatus within a remote station for triggering a broadcast of a transmission parameters message from a base station, comprising:

a memory element; and

a processing element configured to execute a set of instructions stored in the memory element, the set of instructions for;

determining whether a stored set of transmission parameters is current;

if the stored set of transmission parameters is not current, then transmitting a re-transmission request on a reverse link channel to a base station; and

if the stored set of transmission parameters is current, then decoding a data packet using the stored set of transmission parameters.

2. The apparatus of claim 1, wherein the reverse link channel is an Acknowledgment (ACK) Channel.

3. The apparatus of claim 2, wherein the re-transmission request has the form of a pattern of ACK signals.

4. The apparatus of claim 2, wherein the re-transmission request has the form of a multiplicity of ACK signals

5. The apparatus of claim 1, wherein the reverse link channel is a Channel Quality Feedback (CQI) Channel.

6. The apparatus of claim 5, wherein the re-transmission request is carried by the fifth bit of a CQI symbol.

7. The apparatus of claim 6, wherein the re-transmission request is carried by the fifth bit of more than one CQI symbol.

8. The apparatus of claim 1, wherein determining whether the stored set of transmission parameters is current comprises:

performing a hand-off from a previous base station to the base station; and

if the hand-off is successfully completed, then determining that the stored set of transmission parameters is not current.

9. The apparatus of claim 1, wherein determining whether the stored set of transmission parameters is current comprises:

attempting to decode the data packet using the stored set of transmission parameters; and

if the data packet cannot be decoded using the stored set of transmission parameters, then determining that the stored set of transmission parameters is not current.

10. In a wireless communication system, an infrastructure element for controlling a broadcast of a control message, comprising:

a memory element; and

a processing element configured to execute a set of instructions stored in the memory element, the set of instructions for;

transmitting the control message to a remote station, herein the control message contains a set of transmission parameters by which a data packet is to be transmitted;

monitoring a reverse link channel for a re-transmission request;

if a re-transmission request arrives on the reverse link channel, then re-transmitting the control message; and

if a re-transmission request does not arrive on the reverse link channel, then transmitting the data packet.

11. The apparatus of claim 10, wherein the reverse link channel is an Acknowledgment (ACK) Channel.

12. The apparatus of claim 11, wherein the re-transmission request has the form of a pattern of ACK signals.

13. The apparatus of claim 11, wherein the re-transmission request has the form of multiple ACK signals.

14. The apparatus of claim 10, wherein the reverse link channel is a Channel Quality Feedback (CQI) Channel.

15. The apparatus of claim 14, wherein the re-transmission request is carried by the fifth bit of a CQI symbol.

16. The apparatus of claim 15, wherein the re-transmission request is carried by the fifth bit of more than one CQI symbol.

17. A method for triggering a re-broadcast of a control channel message, comprising:

determining whether a set of transmission parameters stored at a remote station is current;

if the stored set of transmission parameters is not current, then transmitting a re-transmission request on a reverse link channel to a base station; and

if the stored set of transmission parameters is current, then decoding a data packet at the remote station using the stored set of transmission parameters.

18. A method for controlling a re-broadcast of a control message, comprising:

transmitting the control message to a remote station, herein the control message contains a set of transmission parameters by which a data packet is to be transmitted;

monitoring a reverse link channel for a re-transmission request;

if a re-transmission request arrives on the reverse link channel, then re-transmitting the control message; and

if a re-transmission request does not arrive on the reverse link channel, then transmitting the data packet.

19. In a wireless communication system, a method for acknowledging missed control messages that are broadcast from a base station to a remote station, comprising:

transmitting a control message from the base station to the remote station, wherein the control message contains a set of transmission parameters for a data packet to be subsequently transmitted to the remote station;

monitoring a reverse link channel at the base station for a re-transmission request from the remote station;

determining whether a set of transmission parameters stored at a remote station is current;

if the stored set of transmission parameters is not current, then transmitting a re-transmission request on the reverse link channel to the base station, whereupon the base station re-transmits the control message; and

if the stored set of transmission parameters is current, then not transmitting a re-transmission request on the reverse link channel to the base station, whereupon the base station transmits the data packet, which the remote station will subsequently receive and decode using the stored set of transmission parameters from the control message.

20. In a wireless communication system, apparatus for controlling the transmission of control messages from a base station, comprising:

means for transmitting a control message from the base station to the remote station, wherein the control message contains a set of transmission parameters for a data packet to be subsequently transmitted to the remote station;

means for monitoring a reverse link channel at the base station for a re-transmission request from the remote station; and

means for determining whether a set of transmission parameters stored at a remote station is current;

means for transmitting a re-transmission request on the reverse link channel to the base station if the stored set of transmission parameters is not current, whereupon the base station re-transmits the control message using the means for transmitting the control message.