Name
Title | ||
|---|---|---|
One-Dimensional Soft-Demapping Algorithms for Rotated QAM and Software Implementation on DSP |
Abstract | ||
|---|---|---|
To improve detection performance of quadrature amplitude modulation (QAM), signal space diversity (SSD) has been exploited and adopted for the second generation of digital video broadcasting (DVB-T2) system. Maximum-likelihood detection (MLD) to get full SSD is avoided because of enormous computational complexity. Its max-log approximated detection (full search algorithm) and subregion based soft-demappers are also too complex to be implemented due to their two-dimensional (2D) Euclidean distance calculation. In particular, the complexity becomes the main burden for the software implementation, which is attractive for multistandard broadcasting receivers. To tackle the main bottleneck, we propose one-dimensional (1D) soft-demappers. By reformulating a rotated QAM signal as two layered pulse amplitude modulation (PAM) signals, the full search algorithm is simplified to an MMSE decorrelation followed by 1D soft-demapping, where Gaussian approximation is used for the interferences. Additional interference cancellation is considered to further suppress its residual interference. For 256-QAM with 4/5 code rate in memoryless Rayleigh channels with/without erasures, the performance gap to the full search is within 0.15 dB at $10^{-3}\ {\hbox{bit}}$ error rate (BER), while the complexity is less than 8%. Due to the significant complexity reduction of the proposed algorithms, the software implementation of a DVB-T2 receiver on DSP is feasible with 73% less computations than the one with the full-search-based soft-demapper. |
Year | DOI | Venue |
|---|---|---|
2013 | 10.1109/TSP.2013.2262681 | IEEE Transactions on Signal Processing |
Keywords | Field | DocType |
subregion based soft-demappers,mld,residual interference suppression,soft-demapping,log likelihood ratio (llr),code rate,1d soft-demapping algorithms,rayleigh channels,digital signal processor (dsp),diversity reception,dsp,signal space diversity (ssd),multistandard broadcasting receivers,gaussian processes,ssd,radiofrequency interference,interference cancellation (ic),software implementation,approximation theory,rotated qam,rotated qam signal,coarse-grained reconfigurable array (cgra) architecture,full search algorithm,gaussian approximation,detection performance improvement,computational geometry,maximum likelihood detection,dvb-t2 receiver,search problems,pam,digital signal processing chips,256-qam,computational complexity,pulse amplitude modulation,codes,minimum mean square error (mmse),digital video broadcasting system,maximum-likelihood detection,quadrature amplitude modulation,signal space diversity,memoryless rayleigh channels,digital video broadcasting,radio receivers,interference suppression,interference cancellation,two layered pulse amplitude modulation signals,mmse decorrelation,2d euclidean distance calculation,noise figure 0.15 db,max-log approximated detection,software defined radio (sdr) | Quadrature amplitude modulation,Decorrelation,Computer science,QAM,Single antenna interference cancellation,Algorithm,Reduction (complexity),Digital Video Broadcasting,Pulse-amplitude modulation,Bit error rate | Journal |
Volume | Issue | ISSN |
61 | 15 | 1053-587X |
Citations | PageRank | References |
4 | 0.52 | 12 |
Authors | ||
5 | ||
Name | Order | Citations | PageRank |
|---|---|---|---|
| Kyeongyeon Kim | 1 | 101 | 13.54 |
| Navneet Basutkar | 2 | 17 | 2.00 |
| Kitaek Bae | 3 | 53 | 7.08 |
| Peng Xue | 4 | 15 | 3.06 |
| Ho Yang | 5 | 31 | 6.03 |