SPARSE CHANNEL ESTIMATION FOR ORTHOGONAL FREQUENCY DIVISION MULTIPLEXED SIGNALS

摘要

A COMPUTATIONALLY EFFICIENT CHANNEL ESTIMATION TECHNIQUE FOR USE WITHIN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) COMMUNICATION SYSTEM DETERMINES COEFFICIENTS OF A CHANNEL TRANSFER FUNCTION BY CALCULATING THE DOT PRODUCTS OF A PILOT VECTOR AND A PLURALITY OF INTERPOLATION VECTORS. ONE DOT PRODUCT IS PREFERABLY CALCULATED FOR EACH SUBCARRIER OF INTEREST WITHIN THE SYSTEM. THE PILOT VECTOR IS EXTRACTED FORM AN OFDM SYMBOL RECEIVED FROM A COMMUNIOCATION CHANNEL.IN A PREFERRED APPROACH, A NUMBER OF INTERPOLATION VECTORS ARE PRECALCULATED AND STORED WITHIN A COMMUNICATION DEVICE FOR SUBSEQUENT USE DURING CHANNEL ESTIMATION AND EQUALIZATION OPERATIONS. THE THECHNIQUE IS HIGHLY FLEXIBLE AND CAN BE IMPLEMENTED USING, FOR EXAMPLE, A VARIABLE USER BLOCK SIZE OR A VARIABLE PILOT VECTOR SIZE. (FIG.5)