In coding theory, an error-correcting code can be encoded either systematically or non-systematically. In a systematic encode, the input data is embedded in the encoded output. Conversely, in a non-systematic code, the output does not contain the input symbols. In this paper, we propose a hybrid encoding scheme for polar codes, in which some data bits are systematically encoded while the rest are non-systematically encoded. Based on the proposed scheme, we design a joint channel estimation and data decoding scheme. We use the systematic bits in the hybrid encoding scheme as pilots for channel estimation. To mitigate the code rate loss caused by the pilots and to provide additional error detecting capability, we propose a dynamic pilot design by building connections between the systematic bits and non-systematic bits. Simulation results show that the performance of the proposed scheme approaches that of the traditional non-systematic polar coding scheme with perfect channel state information (CSI) with the increase of SNR.

翻译：在编码理论中，纠错码可采用系统编码或非系统编码方式。系统编码将输入数据嵌入编码输出中，而非系统编码的输出不包含输入符号。本文提出一种极化码的混合编码方案，其中部分数据比特采用系统编码，其余比特采用非系统编码。基于该方案，我们设计了一种联合信道估计与数据解码方法。利用混合编码方案中的系统比特作为导频进行信道估计。为弥补导频导致的码率损失并提供额外的检错能力，我们通过建立系统比特与非系统比特之间的关联，提出一种动态导频设计方法。仿真结果表明，随着信噪比的增加，所提方案的性能趋近于具有完美信道状态信息（CSI）的传统非系统极化编码方案。