In this paper, we propose efficient parity allocation schemes when rateless codes are used in satellite communication systems in conjunction with an adaptive coding and modulation (ACM) scheme. ACM schemes are widely used in modern satellite communication systems to maintain the required error rate performance under channel impairment (such as rain fading observed in high‐frequency bands). The performance enhancement of ACM can be achieved by providing a good channel prediction and mode allocation method. In the case of a channel prediction or allocation error, rateless codes can be used as an effective means of retransmission to compensate for the performance degradation. After investigating the performance behaviour of rateless codes combined with ACM, we derive a mathematical formula to find the optimum parity length of the rateless code to be retransmitted to satisfy the target performance requirements. Simulation results described in this paper show that the proposed method can be used to enhance the error performance as well as spectral efficiency.

中文翻译：

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卫星系统具有自适应奇偶校验分配的无速率码

在本文中，我们结合自适应编码和调制（ACM）方案，提出了在卫星通信系统中使用无速率码时的有效奇偶校验分配方案。ACM方案广泛用于现代卫星通信系统中，以在信道受损（例如在高频带中观察到雨衰）下维持所需的误码率性能。通过提供良好的信道预测和模式分配方法，可以提高ACM的性能。在信道预测或分配错误的情况下，可以使用无速率码作为重传的有效手段，以补偿性能下降。在研究了无速率代码与ACM相结合的性能行为之后，我们导出一个数学公式，以找到要重发的无速率代码的最佳奇偶校验长度，以满足目标性能要求。本文描述的仿真结果表明，该方法可用于提高误差性能以及频谱效率。