| Abstrakt: |
Objective The commonly used max-log-map algorithm reduces the complexity of soft information computation compared to the log-map algorithm. However, it still consumes a large number of resources for high-order Orthogonal Amplitude Modulation (QAM), such as 8QAM, 16QAM Probability Shaping (PS), and 64QAM PS. Methods 8QAM adopts the method of constellation region division, and the soft information is represented by the distance information from the received symbol of the perpendicular of the nearest bit 0 and bit 1. The distance information is simplified and calculated using angle rotation and regional symmetry. For 16QAM PS and 64QAM PS distributed by non Maxwell Boltzmann (MB) distribution, the central boundary between the edges of the region where bit 1 is located and the central boundary between bit 0 on both sides of the region bit 1 no longer coincide. The region merging approximation is used to handle the region ownership between the two boundaries, and the max-log-map expression is factorized to simplify the distance difference to calculate the soft information. The oft information of 16QAM PS and 64QAM PS based on MB distribution can be obtained by simplifying the soft information expression of non MB distribution. Results After the above simplification, the multiplication and addition/subtraction times of 8QAM soft information calculation were reduced from 48 and 75 times to 12 and 16 times respectively with a degradation of only about 0.05 dB; The 16QAM PS with MB distribution has 192 multiplication times and 260 addition/subtraction times reduced to 2 and 4 times, respectively, resulting in a degradation of only about 0. 05 dB. Higher order 64QAM PS has a greater reduction in resource consumption reduced the multiplication and addition/subtraction times from 1 152 and 1 542 times to 3 and 6 times, respectively. Conclusion This article proposes a soft information calculation method suitable for 8QAM and MB distribution of 16QAM PS, MB distribution of 64QAM PS, non MB distribution of 16QAM PS, and non MB distribution of 4QAM PS. When the probability satisfies the MB distribution, the soft information calculation method suitable for non MB distribution can be converted into the MB distribution calculation method. When the shaping factor is 0, the expression based on the MB distribution can be converted into a uniformly distributed soft information calculation formula. The soft information calculation for non MB distribution, MB distribution, and uniformly distributed probability can be designed uniformly on the same circuit, improving circuit reuse rate and reducing the hardware resource consumption. [ABSTRACT FROM AUTHOR] |
