tailieunhanh - Báo cáo hóa học: " Research Article Joint Multilevel Turbo Equalization and Continuous Phase Frequency Shift Keying"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Joint Multilevel Turbo Equalization and Continuous Phase Frequency Shift Keying | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2008 Article ID 458785 8 pages doi 2008 458785 Research Article Joint Multilevel Turbo Equalization and Continuous Phase Frequency Shift Keying Oguz Bayat 1 Niyazi Odabasioglu 2 Onur Osman 3 Osman N. Ucan 2 Masoud Salehi 4 and Bahram Shafai4 1 Electronics and Communication Engineering Department Beykent University Buyukcekmece 34500 Istanbul Turkey 2 Electrical and Electronics Engineering Department Istanbul University Avcilar 34320 Istanbul Turkey 3 Electronics and Telecommunications Engineering Department Engineering Faculty Halic University Sisli 34381 Istanbul Turkey 4 Electrical and Computer Engineering Northeastern University 360 Huntington Avenue Boston MA 02115 USA Correspondence should be addressed to Oguz Bayat obayat@ Received 2 May 2008 Revised 21 July 2008 Accepted 31 December 2008 Recommended by Huaiyu Dai A novel type of turbo coded modulation scheme called multilevel turbo coded-continuous phase frequency shift keying MLTC-CPFSK is designed to improve the overall bit error rate BER and bandwidth efficiency. Then this scheme is combined with a new double decision feedback equalizer DDFE to remove the interference and to enhance BER performance for the intersymbol interference ISI channels. The entire communication scheme is called multilevel turbo equalization-continuous phase frequency shift keying MLTEQ-CPFSK . In these schemes parallel input data sequences are encoded using the multilevel scheme and mapped to CPFSK signals to obtain a powerful code with phase continuity over the air. The performances of both MLTC-CPFSK and MLTEQ-CPFSK systems were simulated over nonfrequency and frequency-selective channels respectively. The superiority of the two level turbo codes with 4CPFSK modulation is shown against the trellis-coded 4CPFSK multilevel convolutional coded 4CPFSK and TTCM schemes. Finally the bit error rate curve of MLTEQ-CPFSK