Framing for an adaptive modulation communication system

Abstract

A system and method for mapping a combined frequency division duplexing (FDD) Time Division Multiplexing (TDM)/Time Division Multiple Access (TDMA) downlink subframe for use with half-duplex and full-duplex terminals in a communication system. Embodiments of the downlink subframe vary Forward Error Correction (FEC) types for a given modulation scheme as well as support the implementation of a smart antenna at a base station in the communication system. Embodiments of the system are also used in a TDD communication system to support the implementation of smart antennae. A scheduling algorithm allows TDM and TDMA portions of a downlink to efficiently co-exist in the same downlink subframe and simultaneously support full and half-duplex terminals.

1 . A base station for wirelessly communicating with a plurality of cellular telephones, comprising:
 a transmitter configured to group the plurality of cellular telephones into groups by the downlink (DL) physical (PHY) mode in which they will receive DL data and encode data into a DL frame, and a receiver configured to receive data from an uplink (UL) frame, the DL frame having
 control information including synchronization information and information about DL transmission resources allocated to the plurality of cellular telephones scheduled to receive DL data in the DL frame, including what portion of the DL transmission resources allocated to the scheduled cellular telephones is allocated for each of the scheduled cellular telephones scheduled to receive DL data in the DL frame, a DL transmission resource being associated with a DL PHY mode, and 
 at least two data blocks with downlink data for the scheduled cellular telephones, each data block having an allocation of a portion of the DL transmission resources and being encoded according to the respective PHY mode; and 
   an antenna system for transmitting the downlink frame, wherein the downlink data is transmitted to at least one of the scheduled cellular telephones,   wherein the control information is transmitted to the scheduled cellular telephones using a PHY mode compatible with cellular telephones scheduled to receive DL data in a DL frame and for cellular telephones scheduled to transmit data in an UL frame.   
     
     
         2 . A base station according to  claim 1 , wherein the base station is operable to update the UL PHY mode and the DL PHY mode based on data traffic requirements and physical layer requirements of the wireless communication system. 
     
     
         3 . A base station according to  claim 2 , wherein the physical layer requirements include one or more of interference minimization, propagation delays and round trip delays. 
     
     
         4 . A base station according to  claim 1 , wherein the DL PHY mode provides information about a DL modulation scheme and a DL coding scheme to be used by the scheduled cellular telephones for decoding the DL data. 
     
     
         5 . A base station according to  claim 1 , wherein the UL PHY mode provides information about an UL modulation scheme and an UL coding scheme to be used by the cellular telephones scheduled to transmit data in the UL frame for encoding the UL data. 
     
     
         6 . A cellular telephone for wirelessly communicating with a base station, comprising:
 an antenna system for receiving, from a base station, a downlink frame having control information including
 synchronization information, 
 information about downlink (DL) transmission resources allocated to cellular telephones scheduled to receive DL data in the DL frame, including what portion of the DL transmission resources allocated to the cellular telephones is allocated for the cellular telephone, a DL transmission resource being associated with a DL physical (PHY) mode, and 
 one or more data blocks with downlink data for the cellular telephone, each data block having a bandwidth allocation in accordance with the information about DL transmission resources and being encoded according to the associated DL PHY mode; and 
   a receiver configured to decode the control information and to decode the downlink data for the cellular telephone from the transmission resources allocated to the cellular telephone, based on the control information,   wherein the control information is transmitted to the terminal in the downlink frame map using a PHY mode compatible with cellular telephones scheduled to receive DL data in a DL frame and for cellular telephones scheduled to transmit data in an uplink (UL) frame.   
     
     
         7 . A cellular telephone according to  claim 6 , further comprising a transmitter for mapping data to an UL frame for transmission to the base station.