This paper presents a comprehensive analysis and performance enhancement of short block length channel detection incorporating training information. The current communication systems' short block length channel detection typically consists of least squares channel estimation followed by quasi-coherent detection. By investigating the receiver structure, specifically the estimator-correlator, we show that the non-coherent term, often disregarded in conventional detection metrics, results in significant losses in performance and sensitivity in typical operating regimes of 5G and 6G systems. A comparison with the fully non-coherent receiver in multi-antenna configurations reveals substantial losses in low spectral efficiency operating areas. Additionally, we demonstrate that by employing an adaptive DMRS-data power adjustment, it is possible to reduce the performance loss gap, which is amenable to a more sensitive quasi-coherent receiver. However, both of the aforementioned ML detection strategies can result in substantial computational complexity when processing long bit-length codes. We propose an approach to tackle this challenge by introducing the principle of block or segment coding using First-Order RM Codes, which is amenable to low-cost decoding through block-based fast Hadamard transforms. The Block-based FHT has demonstrated to be cost-efficient with regards to decoding time, as it evolves from quadric to quasi-linear complexity with a manageable decline in performance. Additionally, by incorporating an adaptive DMRS-data power adjustment technique, we are able to bridge/reduce the performance gap with respect to the conventional maximum likelihood receiver and attain high sensitivity, leading to a good trade-off between performance and complexity to efficiently handle small payloads.

翻译：本文针对融合训练信息的分组长度信道检测进行了全面分析与性能提升研究。现有通信系统中的短分组长度信道检测通常采用最小二乘信道估计后接准相干检测的方案。通过深入分析接收机结构（特别是估计-相关器结构），我们发现传统检测度量中常被忽略的非相干项在5G和6G系统的典型工作模式下会导致显著的性能与灵敏度损失。在多天线配置条件下与全非相干接收机对比表明，该损失在低频谱效率工作区域尤为突出。此外，我们证实通过采用自适应解调参考信号-数据功率调整技术，能够缩小性能损失差距，从而适配灵敏度更高的准相干接收机。然而，前述两种最大似然检测策略在处理长比特码字时均会产生显著的计算复杂度。为此，我们提出采用基于一阶RM码的分组/段编码原则，通过基于分组的快速哈达玛变换实现低成本译码。基于分组的快速哈达玛变换在译码时间方面展现出成本效益，其复杂度从二次型演变为准线性型，同时仅带来可控的性能下降。进一步结合自适应解调参考信号-数据功率调整技术，我们能够缩小/弥补与传统最大似然接收机的性能差距，实现高灵敏度接收，从而在性能与复杂度之间取得良好平衡以高效处理小数据包。