Multiplex communications – Generalized orthogonal or special mathematical techniques – Quadrature carriers
Reexamination Certificate
2004-02-09
2009-06-23
Jung, Min (Department: 2616)
Multiplex communications
Generalized orthogonal or special mathematical techniques
Quadrature carriers
C370S210000
Reexamination Certificate
active
07551545
ABSTRACT:
For subband-based OFDM demodulation, a “partial” Fourier transform is performed on a sequence of N input samples for an OFDM symbol to obtain Ncreceived symbols for a group of Ncdata subbands, where Nc·L=N and L>1. For the partial Fourier transform, the N input samples are rotated with a phasor to obtain N rotated input samples, which are accumulated (for each set of L samples) to obtain Nctime-domain values. An Nc-point FFT is performed on the Nctime-domain values to obtain the Ncreceived symbols. Channel gain estimates for the data subbands are also obtained, for example, by performing a partial Fourier transform to obtain received pilot symbols, an inverse FFT to obtain time-domain channel gain values, and an FFT to obtain channel gain estimates for the data subbands. The received symbols are processed with (e.g., equalized by) the channel gain estimates to obtain recovered data symbols.
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Braden Stanton
Jung Min
Minhas Sandip S.
QUALCOMM Incorporated
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