Acknowledging missed messages broadcast on a control channel

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 channel.

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 . 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.