Systems and methods for uplink signaling using time-frequency resources

Abstract

Methods, base stations and access terminals for uplink signaling are provided. Resource request channel characteristics such as location in time-frequency, sequence, time slot, are assigned to each access terminal to distinguish their resource requests from the resource requests of other access terminals. Access terminals make requests using a resource request on a resource request channel having the assigned characteristics. The base station can then determine which access terminal transmitted the resource request based on the resource request channel characteristics of the resource request channel upon which the resource request was received. The base station then transmits a response to the request which may for example be a new resource allocation, a default allocation or a renewal of a previous allocation.

What is claimed is: 
     
         1 . A method for uplink signaling between a base station and an access terminal of a plurality of access terminals, the method comprising:
 by the base station:   assigning resources for a resource request to the access terminal, the assigned resources comprising periodic time-frequency resources of an orthogonal frequency division multiplexing (OFDM) based signaling scheme; and   receiving the resource request combined with acknowledge (ACK) and/or negative acknowledge (NACK) feedback from the access terminal,   wherein the resource request is spread over a plurality of subcarriers in one or more OFDM symbols of the assigned resources using at least one orthogonal spreading sequence.   
     
     
         2 . The method of  claim 1 , wherein the periodic time-frequency resources comprise localized or distributed time-frequency resources in a plurality of OFDM symbols and a plurality of sub carriers. 
     
     
         3 . The method of  claim 1 , wherein the resource request comprises an indicator or a flag. 
     
     
         4 . The method of  claim 3 , wherein the resource request comprises a request for uplink resources for the access terminal. 
     
     
         5 . The method of  claim 1 , further comprising the base station identifying the access terminal from which the resource request is transmitted based at least in part on the resources on which the resource request is received. 
     
     
         6 . The method of  claim 1 , wherein the resources for the resource request assigned to the access terminal comprise resources overlaid on time-frequency resources used for uplink control signaling. 
     
     
         7 . The method of  claim 1 , wherein the resources for the resource request assigned to the access terminal comprise time-frequency resources assigned at least in part to a second access terminal of the plurality of access terminals, the second access terminal using at least one orthogonal spreading sequence that differs from the at least one orthogonal spreading sequence used by the access terminal. 
     
     
         8 . A base station configured to receive uplink signaling from an access terminal of a plurality of access terminals, the base station comprising:
 wireless circuitry for performing wireless communication with the plurality of access terminals;   processing circuitry in communication with the wireless circuitry, wherein the processing circuitry is configured to cause the base station to:
 assign resources for a resource request to the access terminal, the assigned resources comprising periodic time-frequency resources of an orthogonal frequency division multiplexing (OFDM) based signaling scheme; and 
 receive the resource request combined with acknowledge (ACK) and/or negative acknowledge (NACK) feedback from the access terminal, 
 wherein the resource request is spread over a plurality of subcarriers in one or more OFDM symbols of the assigned resources using at least one orthogonal spreading sequence. 
   
     
     
         9 . The base station of  claim 8 , wherein the periodic time-frequency resources comprise localized or distributed time-frequency resources in a plurality of OFDM symbols and a plurality of subcarriers. 
     
     
         10 . The base station of  claim 8 , wherein the resource request comprises an indicator or a flag. 
     
     
         11 . The base station of  claim 10 , wherein the resource request comprises a request for uplink resources for the access terminal. 
     
     
         12 . The base station of  claim 8 , wherein the processing circuitry is further configured to cause the base station to identify the access terminal from which the resource request is transmitted based at least in part on the resources on which the resource request is received. 
     
     
         13 . The base station of  claim 8 , wherein the resources for the resource request assigned to the access terminal comprise resources overlaid on time-frequency resources used for uplink control signaling. 
     
     
         14 . The base station of  claim 8 , wherein the resources for the resource request assigned to the access terminal comprise time-frequency resources assigned at least in part to a second access terminal of the plurality of access terminals, the second access terminal using at least one orthogonal spreading sequence that differs from the at least one orthogonal spreading sequence used by the access terminal. 
     
     
         15 . A non-transitory computer-readable medium storing instructions that, when executed by processing circuitry of a base station, case the base station to:
 assign resources for a resource request to the access terminal, the assigned resources comprising periodic time-frequency resources of an orthogonal frequency division multiplexing (OFDM) based signaling scheme; and   receive the resource request combined with acknowledge (ACK) and/or negative acknowledge (NACK) feedback from the access terminal,   wherein the resource request is spread over a plurality of subcarriers in one or more OFDM symbols of the assigned resources using at least one orthogonal spreading sequence.   
     
     
         16 . The non-transitory computer-readable medium of  claim 15 , wherein the periodic time-frequency resources comprise localized or distributed time-frequency resources in a plurality of OFDM symbols and a plurality of subcarriers. 
     
     
         17 . The non-transitory computer-readable medium of  claim 15 , wherein the resource request comprises an indicator or a flag that indicates a request for uplink resources for the access terminal. 
     
     
         18 . The non-transitory computer-readable medium of  claim 15 , wherein execution of the instructions by processing circuitry further cause the base station to identify the access terminal from which the resource request is transmitted based at least in part on the resources on which the resource request is received. 
     
     
         19 . The non-transitory computer-readable medium of  claim 15 , wherein the resources for the resource request assigned to the access terminal comprise resources overlaid on time-frequency resources used for uplink control signaling. 
     
     
         20 . The non-transitory computer-readable medium of  claim 15 , wherein the resources for the resource request assigned to the access terminal comprise time-frequency resources assigned at least in part to a second access terminal of the plurality of access terminals, the second access terminal using at least one orthogonal spreading sequence that differs from the at least one orthogonal spreading sequence used by the access terminal.