Abstract:

A method of time domain synchronous orthogonal frequency division multiplexing (TDS-OFDM) communication, including the steps of: preparing OFDM-body; generating pseudo random (PN) sequence as a training signal; manipulating the PN sequence to concentrate the energy distribution thereof to the same bandwidth of sub-carriers of the OFDM-body; offsetting the manipulated PN sequence to align with frequency spectrum of the sub-carriers; and inserting the offset PN sequence as prefix of a TDS-OFDM data frame. The manipulating step may include the step of repeating the PN sequence by N times, wherein the spectrum of the repeated PN sequence concentrates on discrete bundles of sub-carriers, i.e., on one sub-carrier every N sub-carriers or M adjacent sub-carriers every MN sub-carriers, where M is an integer determined by the time duration ratio of the OFDM body and prefix. Alternatively, the manipulating step may include the step of expanding the PN sequence by N times, wherein the spectrum of the expanded PN sequence concentrates on a block of continual adjacent sub-carriers, the bandwidth of the PN sequence is 1/N of the whole bandwidth.

Description:

CROSS-REFERENCES TO RELATED APPLICATIONS

This application does not have any related US patent applications at the time of filing.

TECHNICAL FIELD

The presently claimed invention relates generally to methods and apparatus for digital multi-carrier modulation and, in particular, to methods and apparatus for Time Division Synchronous Orthogonal Frequency Division Multiplexing (TDS-OFDM).

BACKGROUND OF THE INVENTION

Orthogonal Frequency Division Multiplexing (OFDM) is one widely utilized multi-carrier based scheme for wired or wireless wideband digital communication systems. One known implementation of OFDM is by the scheme of Cyclic Prefix OFDM (CP-OFDM) in which tail part of OFDM body is used to stuff the guard interval between two con ...

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