Physical random access channel for slotted wireless communication systems

Abstract

In one embodiment, a physical random access channel (PRACH) is used in communicating in a slotted wireless communication system. The slotted system uses repeating radio frame structure for communication. The PRACH is associated with a set of characteristics comprising: a set of channelization codes associated with the PRACH; at least one time slot associated with the PRACH; and a set of subchannels associated with the PRACH, the subchannels associated with a single time slot of the radio frames. In another embodiment, access service classes (ASCs) are separted in a wireless slotted communication system. Each ASC is associated with a unique set of channelization codes and subchannels of a physical random access channel (PRACH). The subchannels are associated with a single time slot of radio frames of the wireless slotted communication system.

What is claimed is:  
     
         1 . A physical random access channel (PRACH) for use in communicating in a slotted wireless communication system, the slotted system using repeating radio frame structure for communication, the PRACH associated with a set of characteristics comprising: 
 a set of channelization codes associated with the PRACH;    at least one time slot associated with the PRACH; and    a set of subchannels associated with the PRACH, the subchannels associated with a single time slot of the radio frames.    
     
     
         2 . The PRACH of  claim 1  wherein the radio frames have associated system frame numbers (SFNs) and each sub channel is associated with specified ones of the SFNs.  
     
     
         3 . The PRACH of  claim 1  wherein the associating each subchannel with specified ones of the SFNs is by a modulo counting of the SFNs.  
     
     
         3 . The PRACH of  claim 1  wherein a number of the subchannels is N and N has a value of either 1, 2, 4 or 8.  
     
     
         4 . The PRACH of  claim 3  wherein an ith subchannel is associated with a SFN by i=SFN mod N.  
     
     
         5 . A method for separating access service classes (ASCs) in a wireless slotted communication system, the method comprising: 
 assigning each ASC with a unique set of channelization codes and subchannels of a physical random access channel (PRACH), the subchannels associated with a single time slot of radio frames of the wireless slotted communication system.    
     
     
         6 . The method of  claim 5  wherein the unique set of channelization codes and subchannels of the PRACH define a partition of that PRACH.  
     
     
         7 . The method of  claim 5  wherein the radio frames have system frame numbers (SFNs) and each subchannel is associated with specified ones of the SFNs.  
     
     
         8 . The method of  claim 5  wherein the associating each subchannel is by a modulo counting of the SFNs.  
     
     
         9 . The method of  claim 8  wherein a number of the subchannels is N and N has a value of either 1, 2, 4 or 8.  
     
     
         10 . The method of  claim 9  wherein an i th  subchannel is associated with a SFN by i=SFN mod N. N.