Masanori Hamamura

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SUMMARY We propose a novel asynchronous direct-sequence code-division multiple access (DS-CDMA) using feedback-controlled spreading sequences (FCSSs) (FCSS/DS-CDMA). At the receiver of FCSS/DS-CDMA, the code-orthogonalizing filter (COF) produces a spreading sequence , and the receiver returns the spreading sequence to the transmitter. Then the transmitter(More)
SUMMARY In this paper, we propose a new modulation named parallel combinatory/high compaction multi-carrier modulation (PC/HC-MCM) using the techniques of parallel combinatory orthogonal frequency division multiplexing (PC-OFDM) and high compaction multi-carrier modulation (HC-MCM). Two types of PC/HC-MCM systems, which are named as modulated PC/HC-MCM(More)
SUMMARY We propose multitone-hopping code-division multiple access (MH-CDMA) using a feedback-controlled hopping pattern (FCHP) (FCHP/MH-CDMA). In the FCHP/MH-CDMA, part of the filter coefficients of an adaptive finite-duration impulse response (FIR) filter receiver are fed back to a transmitter, in which they are used as an updated hopping pattern. Each(More)
To make use of the sparsity property of broadband multipath wireless communication channels, we mathematically propose an l p -norm-constrained proportionate normalized least-mean-square (LP-PNLMS) sparse channel estimation algorithm. A general l p -norm is weighted by the gain matrix and is incorporated into the cost function of the proportionate(More)
SUMMARY A novel peak-to-average power ratio (PAR) control algorithm for feedback-controlled multitone-hopping code-division multiple access (FC/MH-CDMA) signals is proposed. In FC/MH-CDMA, since each chip consists of plural tones, the energy consumption due to a large PAR is not negligible at the transmitter. The proposed PAR control algorithm iteratively(More)
This paper presents BER performance of several FH/M-ary multilevel FSK (abbr.MMFSK) and OFDM (MC-SS type) systems using limiters, and compares their properties in an AWGN channel and in a high frequency power-line. The proposed MMFSK systems are modified by using a parallel system and a multi-tone combination system. As a limiter, a soft clipper is adopted.(More)