Systems and methods for creating in a transmitter a stream of symbol frames configured for efficient processing in a receiver

Abstract

A system and method of creating frames comprised of blocks, where each block comprises data symbols corresponding to a higher order quadrature modulation format and support symbols corresponding to a lower order modulation format. One or more of the blocks can further comprise markers comprising distinct symbol patterns. The markers can mark the start of each frame and/or another location in the frame. The support symbols can be in a common location in each block.

We claim: 
     
         1 . A method of generating, in a communications transmitter, a stream of symbol blocks, the method comprising:
 providing in a first of the symbol blocks a distinct symbol pattern identifying a start of a frame of the symbol blocks;   providing in each of at least the first and a second of the symbol blocks a set of data symbols comprising a first set of user bits modulated in accordance with a first modulation format;   providing in each of at least the first and the second of the symbol blocks a set of support symbols comprising a second set of the user bits modulated in accordance with a second modulation format;   and   outputting each of at least the first and the second of the symbol blocks for transmission to a remote receiver, wherein the first modulation format is of a different modulation order than the second modulation format.