A ZCZ-CDMA system with BFSK modulation

• Published in: International journal of communication systems Vol. 25; no. 12; pp. 1620 - 1638
• Main Authors: Huang, Jincheng, Matsufuji, Shinya, Matsumoto, Takahiro, Kuroyanagi, Noriyoshi
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.12.2012; Wiley Subscription Services, Inc
• Subjects: CDMA; modulation; Rayleigh fading; short-range communication; spread spectrum; ZCZ code
• ISSN: 1074-5351; 1099-1131
• DOI: 10.1002/dac.2313

SUMMARY A quasi‐timing synchronous code division multiple access (CDMA) system called ZCZ‐CDMA, which uses a set of sequences with a zero‐correlation zone called ZCZ code as a spreading code, is useful for short‐range wireless communications because of its excellent properties such as co‐channel interference‐free performance, simplified hardware design, and low transmit power as well as fast frame synchronization capability. In this paper, a ZCZ‐CDMA system with binary frequency‐shift keying (BFSK) modulation called BFSK‐ZCZ‐CDMA is proposed. This system is characterized by using a pair of balanced ZCZ codes for spreading and transmitting the two spread components over the respective keying carrier frequencies. Its bit error rate performance, compared with those of existing BPSK‐ZCZ‐CDMA, ASK‐ZCZ‐CDMA, and CDMA systems using the other spreading codes, is evaluated in theory and simulation. The bit error rate performance of the three ZCZ‐CDMA systems over additive white Gaussian noise and Rayleigh fading channels are formulated. It is proved that BFSK‐ZCZ‐CDMA is much more robust in anti‐fading performance and low transmit power in such an environment that fading distributions on the keying frequencies are independent mutually. Fading versus frequency characteristics are also investigated. Copyright © 2012 John Wiley & Sons, Ltd. This paper proposes a ZCZ‐CDMA system with binary frequency‐shift keying modulation called BFSK‐ZCZ‐CDMA. This system is characterized by using a pair of balanced zero‐correlation zone codes for spreading and transmitting the two spread components over the respective keying carrier frequencies. It is proved that BFSK‐ZCZ‐CDMA is much more robust in anti‐fading performance and low transmit power in such an environment that fading distributions on the keying frequencies are independent mutually.