Low-complexity de-mapping algorithms for 64-APSK signals

  • Bao, Junwei (College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics) ;
  • Xu, Dazhuan (College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics) ;
  • Zhang, Xiaofei (College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics) ;
  • Luo, Hao (College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics)
  • Received : 2017.12.01
  • Accepted : 2018.10.08
  • Published : 2019.06.03


Due to its high spectrum efficiency, 64-amplitude phase-shift keying (64-APSK) is one of the primary technologies used in deep space communications and digital video broadcasting through satellite-second generation. However, 64-APSK suffers from considerable computational complexity because of the de-mapping method that it employs. In this study, a low-complexity de-mapping method for (4 + 12 + 20 + 28) 64-APSK is proposed in which we take full advantage of the symmetric characteristics of each symbol mapping. Moreover, we map the detected symbol to the first quadrant and then divide the region in this first quadrant into several partitions to simplify the formula. Theoretical analysis shows that the proposed method requires no operation of exponents and logarithms and involves only multiplication, addition, subtraction, and judgment. Simulation results validate that the time consumption is dramatically decreased with limited degradation of bit error rate performance.


Supported by : National Natural Science Foundation of China


  1. R. D. Gaudenzi et al., Performance analysis of Turbo‐coded APSK modulations over nonlinear satellite channels, IEEE Trans. Wirel. Commun. 5 (2006), no. 9, 2396-2407.
  2. CCSDS 131.2-B-1, Recommendation for space data system standards: Flexible advanced coding and modulation scheme for high rate telemetry applications, The Consultative Committee for Space Data Systems (CCSDS), Washington, DC, USA, 2012.
  3. ETSI EN 302 307 v1.2.1, Digital video broadcasting (DVB); Second generation framing structure, channel coding and modulation systems for broadcasting, interactive services, news gathering and other broadband satellite applications (DVB-S2), European Telecommunications Standards Institute, France, 2009.
  4. E. Yao et al., A simplified soft decision demapping algorithm of 16-APSK signals in AWGN channel, in Int. Conf. Netw. Security, Wireless Commun. Trusted Comput., Wuhan, China, Apr. 2010, pp. 103-106.
  5. K. Cho et al., An approximated soft decoding algorithm of 16-APSK signal for DVB-S2, in Int. Conf. Consumer Electron., Hiroshima, Japan, Jan. 2007, pp. 1-2.
  6. J. Lee et al., Soft‐decision demapping algorithm with low computational complexity for coded 4+12 APSK, Int. J. Satell. Commun. Netw. 31 (2013), no. 3, 103-109.
  7. M. Zhang et al., Efficient soft demodulation scheme for digital video broadcasting via satellite - second generation system, IET Commun. 8 (2014), no. 1, 124-132.
  8. M. Anedda et al., 64‐APSK constellation and mapping optimization for satellite broadcasting using genetic algorithms, IEEE Trans. Broadcast. 62 (2016), no. 1, 1-9.
  9. X. Xiang et al., Constellation labeling optimization for bit‐interleaved coded APSK, Sensors Syst. Space Appl. IX 98380Q, (2016), 1-11.
  10. A. R. Ndjiongue et al., Closed‐form SER expression for APSK based on the kite structure, IEEE Commun. Lett. 21 (2017), no. 10, 2181-2185.
  11. M. Sandell et al., Efficient demodulation of general APSK constellations, IEEE Signal Process. Lett. 23 (2016), no. 6, 868-872.
  12. Q. Xie et al., Simplified soft demapper for APSK with product constellation labeling, IEEE Trans. Wirel. Commun. 11 (2012), no. 7, 2649-2657.
  13. M. Zhang et al., Near ML soft bit estimation for APSK with very low complexity, in Vehicular Technol. Conf., Nanjing, China, May 2016, pp. 1-5.
  14. K. Yan et al., Non‐uniform APSK optimization for BICM systems, Tsinghua Sci. Technol. 20 (2015), no. 2, 175-181.
  15. S. H. Choi et al., The mapping and demmaping algorithms for high order modulation of DVB-S2 systems, in Asia-Pacific Conf. Commun., Busan, Rep. of Korea, Aug. 2006, pp. 1-5.
  16. V. B. Olivatto et al., Simplified method for log‐likelihood ratio approximation in high‐order modulations based on the Voronoi decomposition, IEEE Trans. Broadcast. 63 (2017), no. 3, 1-7.
  17. W. You et al., An efficient soft de-mapping algorithm for APSK signals, in Int. Conf. Mechatronics Inform. Technol., Shenzhen, China, Aug. 2016, pp. 100-104.
  18. E. Larsson et al., Fixed‐complexity soft MIMO detection via partial marginalization, IEEE Trans. Signal Process. 56 (2008), no. 8, 3397-3407.
  19. L. Wang et al., A simplified bit metric calculation method for high‐order PSK, Sci. China 56 (2012), no. 7, 1-9.