A Multi-User Detection Scheme Based on Polar Code Construction in Downlink Underwater Acoustic OFDM Communication System
A Multi-User Detection Scheme Based on Polar Code Construction in Downlink Underwater Acoustic OFDM Communication System
复制标题
DOI：
10.1109/access.2019.2916995
复制
发表时间：
2019
期刊：
影响因子：
3.9
通讯作者：
Gang Qiao;Siyu Xing;Feng Zhou
中科院分区：
文献类型：
--
作者：
Gang Qiao;Siyu Xing;Feng Zhou
本文提出了一种新的极化码构造方案，该方案适用于采用正交频分复用(OFDM)的水声多用户通信系统。我们使用极性码，因为极性码的码率可以任意设计。此外，极性码还可以用于创建嵌套码结构，该嵌套码结构被分成几个子集(码本)。我们利用极性码的这一特性，将信息比特放在码本中，以避免所有用户的重叠。这有助于消除功率分配系数的影响，充分利用发射节点换能器的功率。此外，该方案通过避免传统方案中信道均衡通常需要的零导频音来最大化每个用户的OFDM子载波资源的利用效率。所提出的方案也不依赖于信道状态信息(CSI)作为先验信息，因为每个用户可以通过使用他们自己的码本独立地解码他们自己的数据，而不需要连续干扰消除(SIC)。仿真和水池实验结果表明，该方案在保证所有用户可靠性的同时，降低了接收机的复杂度，最适合于下行水声多用户通信系统。
In this paper, we propose a novel polar code construction scheme, suitable for the underwater acoustic (UWA) multi-user communication system using orthogonal frequency division multiplexing (OFDM). We use the polar codes because the code rate of a polar code can be arbitrarily designed. Moreover, the polar codes can also be used to create a nested code structure, divided into several subsets (codebook). We exploit this feature of the polar codes and place the information bits in the codebook to avoid superimposition of all the users. This helps to eliminate the influence of the power allocation coefficient and make full use of the power of the transducer at the transmitted node. Furthermore, the proposed scheme maximizes the utilization efficiency of the OFDM subcarrier resource for each user by avoiding null pilot tones that are usually required for channel equalization in the traditional schemes. The proposed scheme also does not depend on the channel state information (CSI) as prior information as each user can decode their own data independently by using their own codebook without successive interference cancellation (SIC). The simulation and tank experiment results demonstrate that the proposed scheme can significantly guarantee the reliability of all the users, and reduces the complexity of the receiver, thus making it most suitable for the downlink UWA multi-user communication systems.