上行SCMA信道估计及性能评估

doi:10.11959/j.issn.1000-0801.2017267

摘要/Abstract

摘要：

针对两种SCMA资源映射方式（RE-Sparse SCMA和RB-Sparse SCMA）和已有的基于ZC序列循环移位正交性和正交覆盖码的导频图样方案，提出了基于频分复用的稀疏导频图样，并且在具有不同频率选择性的信道下进行了仿真评估，同时对SCMA的SIC-MPA接收算法提出了目标用户选择策略。从仿真结果可以看出，在慢衰落信道前提下，正交覆盖码和频分复用都可以明显提升信道估计性能，RB-Sparse SCMA 与RE-Sparse SCMA相比，导频图样本身有一定的频域正交性，且性能更好，因此能更灵活地适用于实际多用户传输场景。

关键词: 5G, 非正交多址, SCMA上行链路, 导频图样, 信道估计, SIC-MPA

Abstract:

There are two types of physical mapping for SCMA named RE-Sparse SCMA and RB-Sparse SCMA.A frequency division multiplexing (FDM) based pilot pattern was proposed for RE-Sparse SCMA,and existing code division multiplexing pilot patterns based on cyclic shift and orthogonal cover code (OCC) were considered.Under different frequency selective channels,simulation and evaluation work for the two mapping schemes of SCMA had done.Besides,a target user selection strategy was proposed for existing SIC-MPA.Analytical simulation results show that both OCC and FDM can improve system performance with slot fading channel.Compared with RE-Sparse SCMA,RB-Sparse SCMA with partially frequency orthogonal pilot pattern enjoys better performance gain,and it is more applicable for realistic multi-user SCMA scenario.

Key words: 5G, non-orthogonal multiple access, uplink SCMA, pilot pattern, channel estimation, SIC-MPA

中图分类号:

TP393

胡显安,曾祥念. 上行SCMA信道估计及性能评估[J]. 电信科学, 2017, 33(11): 169-178.

Xian’an HU,Xiangnian ZENG. Channel estimation and performance analysis for uplink SCMA system[J]. Telecommunications Science, 2017, 33(11): 169-178.

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参数	取值
载频/GHz	2
系统带宽/MHz	10
子载波间距/kHz	15
信道模型	TDL-C 300 ns/ETU
移动速度/（km·h^-1）	3
分配RB数	4，12
仿真时长/s	10
信道编码	Turbo，1/3
调制编码	C84
发送天线配置	1
接收天线配置	2