It is widely recognized that OFDM schemes are well-suited for high rate transmission in severely time-dispersive environments; however, the strong envelope fluctuations of OFDM signals lead to power amplification difficulties. This paper considers the use of a CEPB-OFDM technique (Constant-Envelope Paired-Burst OFDM) allowing a power-efficient, grossly nonlinear power amplification, within an ATM-compatible broadband wireless system which operates at mm-wave frequencies. A convolutional code isemployed to cope with the frequency notches inherent to the frequency selective fading and the coded bits are interleaved and mapped on the subcarriers under a frequency-domain DQPSK rule. The receiver design is considered for both conventionaldifferential detectors and coherent detectors, with or without space diversity. It is shown that the proposed receiver structures are powerful enough to cope with time dispersion effects associated to typical indoor scenarios: service bit rates over100Mbit/s are achievable through coherent receivers without diversity and through differential receivers when two-branch space diversity is employed.
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