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ComputersComputer Systems

Differential Space-Time Modulation for Wideband Wireless Networks

Authors: Hongbin Li; STEVENS INST OF TECH HOBOKEN NJ
Abstract:
This project investigated differential modulation for broadband wireless communication systems equipped with multiple transmit antennas operating in frequency-selective channels. The objective was to provide full spatio-spectral diversity and coding gain at affordable decoding complexity without the burden of estimating the underlying space-time frequency-selective channel. The authors have developed two differential space-time modulation schemes tailored to frequency-selective channels. These schemes offer different trade-offs in dealing with time-selective versus frequency-selective fading channels. When applied along with a full-diversity spectral code, these schemes achieve full spatio-spectral diversity and significant coding gain. They also have examined the code design problem for the system under consideration, and obtained optimum code design criteria. For practical spectral encoding, they have developed a class of minimum-length full-diversity codes, referred to as linear constellation decimation (LCD) codes, which offer significant coding gain at modest decoding complexity. They also have developed a differential space-time modulation scheme using amplitude-phase shift keying (APSK) symbols, which are more efficient than conventional PSK-based differential space-time techniques.

Limitations: APPROVED FOR PUBLIC RELEASE
Description: Final progress rept. 1 Jul 2003-30 Jun 2006
Pages: 7
Report Date: 30 SEP 2006
Contract Number: DAAD190310184
Report Number: A934954
Keywords relating to this report:
*AMPLITUDE MODULATION
*BROADBAND
*COMMUNICATIONS NETWORKS
*MULTICHANNEL COMMUNICATIONS
*PHASE MODULATION
*SPACE DIVERSITY COMMUNICATIONS
*WIRELESS LINKS
CODE DIVISION MULTIPLE ACCESS
CODING
ERROR ANALYSIS
FADING_ELECTROMAGNETIC WAVES_
FREQUENCY DIVISION MULTIPLEXING
FREQUENCY DOMAIN
GAIN
MULTIPLE BEAM ANTENNAS
SIGNAL PROCESSING
TIME DOMAIN
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