Title :
Soft-demodulation algorithm for 64QAM and it´s application in HSPA+
Author :
Sun Qiang ; Qi Wenfei
Author_Institution :
Sch. of Electron. & Inf. Eng., Beijing Jiao tong Univ., Beijing, China
Abstract :
QAM is very favorable in high speed communication systems, because it could enhance the frequency spectrum utilization of them. In this paper, consists of two aspects. On the one hand, the theoretical algorithm of bit-level soft demodulation for 64QAM is analyzed, and two simplified algorithm to calculate LLR is developed. On the other hand, an advanced Hybrid ARQ (HARQ) with chase combing is presented, employing 64QAM modulation and signal constellation rearrangement; also introduce the application in HSPA+.
Keywords :
demodulation; quadrature amplitude modulation; 64QAM; HSPA+; bit-level soft demodulation; frequency spectrum utilization; high speed communication systems; signal constellation rearrangement; soft-demodulation algorithm; 64Quadrature Amplitude Modulation (64QAM); HSPA Evolution(HSPA+); Hybrid ARQ; Log-Likelihood Ratio (LLR); Soft-Demodulation Algorithm and Application; constellation rearrangement;
Conference_Titel :
Signal Processing (ICSP), 2012 IEEE 11th International Conference on
Conference_Location :
Beijing
Print_ISBN :
978-1-4673-2196-9
DOI :
10.1109/ICoSP.2012.6492042
