Title :
2D Markovian SS codes flatten time-frequency distribution of signals in asynchronous Gabor division CDMA systems
Author :
Kohda, Tohru ; Jitsumatsu, Yutaka ; Aihara, Kazuyuki
Author_Institution :
Dept. of Inf., Kyushu Univ., Fukuoka, Japan
Abstract :
We propose a Gabor division (GD)-CDMA system which permits time and frequency offsets. Negatively correlated time- and frequency-domain spreading codes have shown to reduce the variances of mutual- and self-interferences. In this paper, we show that such negatively correlated spreading codes have another important property that they flatten the time-frequency energy distributions of signals in GD-CDMA system.
Keywords :
Markov processes; code division multiple access; codes; radiofrequency interference; signal processing; spread spectrum communication; time-domain analysis; time-frequency analysis; 2D Markovian SS codes; Gabor division system; asynchronous gabor division CDMA systems; correlated time-domain spreading codes; flatten time-frequency distribution; frequency offsets; frequency-domain spreading codes; mutual-interference variance; negative correlated spreading codes; self-interferences; signal distribution; spread spectrum code; Frequency conversion; Markov processes; Multiaccess communication; RNA; Time frequency analysis; Timing; Ambiguity function; CDMA; Spread Spectrum code; Time and frequency offsets; interference;
Conference_Titel :
Acoustics, Speech and Signal Processing (ICASSP), 2011 IEEE International Conference on
Conference_Location :
Prague
Print_ISBN :
978-1-4577-0538-0
Electronic_ISBN :
1520-6149
DOI :
10.1109/ICASSP.2011.5946687
