A bandwidth-power efficient modulation scheme based on quaternary quasi-orthogonal sequences

• Published in: IEEE communications letters Vol. 7; no. 7; pp. 293 - 295
• Main Authors: KIM, Youhan, CHEUN, Kyungwhoon, YANG, Kyeongcheol
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.07.2003; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; AWGN channels; Bandwidth; Channel capacity; Costs; Degradation; Demodulation; Demodulators; Exact sciences and technology; Frequency shift keying; Hardware; Microwave integrated circuits; Modulation; Phase modulation; Power efficiency; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Walsh transforms; AWGN channels; Performance evaluation; quasi-orthogonal sequences (QOSs); Matched filter; noncoherent demodulation; Modulation; Orthogonal modulation; Symbol error rate; Demodulation; Quadrature phase shift keying; Walsh transformation
• ISSN: 1089-7798; 1558-2558
• DOI: 10.1109/LCOMM.2003.813821

A novel modulation scheme suitable for noncoherent demodulation based on quaternary quasi-orthogonal sequences is proposed. Compared to orthogonal modulation, the controlled quasi-orthogonality between the sequences allows significantly increased bandwidth efficiency with little or no degradation in power efficiency. A hardware efficient demodulator structure using fast Walsh transforms is also presented.