摘要
编码正交频分复用(OFDM)因其频带利用率高、抗多径能力强等特点而成为高清视频无线传输的首选物理层技术,而频率选择性衰落是宽带无线信道的固有特性,信道均衡可有效对抗由于无线信道频率选择性衰落引入的码间干扰,是基于OFDM的高清无线传输系统的核心关键技术之一。详细介绍了OFDM系统的原理,深入分析了无线信道对OFDM信号的影响,提出了一种基于导频信号的频域均衡算法,深入分析了该算法原理,从导频设计、信道插值算法和信道估计准则等方面对该算法进行了优化设计和电路实现,在Xilinx Spartan 6FPGA开发平台上进行了算法验证,最后给出了Modelsim 6.5仿真结果。仿真表明,所设计的信道均衡算法可有效补偿无线信道对信号的影响,实现数据正确解调,且算法复杂度低、占用硬件资源小,可满足系统设计需求。
Orthogonal frequency division multiplexing （OFDM） has become the preferred physical layer technology for high-definition video wireless transmission due to its high frequency band utilization and strong anti-multipath capability. However, frequency-selective fading is an inherent characteristic of broadband wireless channels. Channel equalization can effectively resist the inter-symbol interference introduced by the frequency-selective fading of wireless channels and which is one of the key technologies of the OFDM-based HD wireless transmission system. The principle of OFDM system is introduced in detail,the influence of wireless channel on OFDM signal is analyzed in this paper. This paper presents a frequency domain equalization algorithm based on pilot signal. The principle of the algorithm is analyzed. The algorithm is designed and implemented from the aspects of pilot pattern design, interpolation algorithm and estimation criterion. The algorithm is validated by Xilinx Spartan 6 FPGA and some simulation results show that the designed channel equalization algorithm can effectively compensate the influence of the wireless channel on the signal to realize a correct demodulation of the data, and the algorithm is low in complexity and small in occupied hardware resources, it can meet the requirements for system design.
作者
徐劲松
何家富
李明宇
王雅慧
李振坤
XU Jin-song;HE Jia-fu;LI Ming-yu;WANG Ya-hui;LI Zhen-kun(Nanjing 6902 Technology Corpration Limited,Nanjing 210009,China)
出处
《时间频率学报》
CSCD
2018年第3期242-250,共9页
Journal of Time and Frequency
基金
2017年江苏省"双创计划"资助项目(苏人才办[2017]37号)
关键词
编码的正交频分复用
无线视频传输
信道均衡
设计与实现
orthogonal frequency-division multiplexing （OFDM）
wireless video transmission
channel equalization
design and implementation
