Title :
Soft output equalization techniques for π/4-DQPSK mobile radio
Author :
Park, Jong Il ; Wicker, Stephen B. ; Owen, Henry L.
Author_Institution :
Sch. of Electr. & Comput. Eng., Georgia Inst. of Technol., Atlanta, GA, USA
Abstract :
The concatenation of an equalizer and a Viterbi decoder is a powerful means for improving the performance of mobile radio. The best system performance is obtained when the Viterbi algorithm is used with soft decisions. The soft output equalizer enables the use of soft decision Viterbi decoding. This paper proposes new soft output adaptive equalization techniques based on the SOVA and the modified-MAP algorithm for π/4-DQPSK mobile radio over multipath fading channels. Simulation results were obtained by using a modified version of the common functional blocks which were used previously by Hamied and Stuber (1996). A complexity analysis is also presented
Keywords :
Viterbi decoding; adaptive equalisers; cellular radio; concatenated codes; differential phase shift keying; digital radio; fading; maximum likelihood decoding; multipath channels; quadrature phase shift keying; time division multiple access; π/4-DQPSK mobile radio; SOVA; Viterbi algorithm; Viterbi decoder; adaptive equalization techniques; common functional blocks; complexity analysis; concatenation; modified-MAP algorithm; multipath fading channels; performance; simulation; soft output equalization techniques; AWGN; Additive white noise; Delay; Equalizers; Filters; Land mobile radio; Maximum likelihood decoding; Maximum likelihood estimation; Modulation coding; Radio transmitters;
Conference_Titel :
Communications, 1997. ICC '97 Montreal, Towards the Knowledge Millennium. 1997 IEEE International Conference on
Conference_Location :
Montreal, Que.
Print_ISBN :
0-7803-3925-8
DOI :
10.1109/ICC.1997.595039
