本文先比较分析了毫米波IEEE 802.11 aj标准中正交频分复用(OFDM)和单载波频域均衡(SC-FDE)两种系统模式的实现流程框图差异以及性能的优劣,然后提出一种IEEE 802.11 aj单载波(SC)超高速WLAN(WirelessLocal Area Network)原型机设计方案,并基于NI-PXIe毫米波平台和LabVIEW语言进行开发实现.系统实现了IEEE 802.1 1aj物理层基带的加(解)扰码、信道编(解)码、星座点映射与解映射、FFT(Fast Fourier Transform)与IFFT、同步、信道估计与均衡、相位补偿等模块.文中重点介绍了同步和均衡模块,其中均衡模块采用分数间隔频域均衡的方法,有效提升系统性能.基带处理均采用WDP(Wide Data Path)数据结构进行并行处理,有效的降低基带处理中FPGA的时钟速率要求.本系统支持多种调制方式,测试结果表明,接收端均衡之后数据星座点聚集度良好,系统误码率低、实时传输速率高,支持高清视频稳定实时传输,具有很强的可行性和应用性.%In this paper,firstly the advantages and disadvantages and flow block diagram of the OFDM and single carrier frequency domain equalization (SC-FDE) modes in IEEE 802.11aj protocol the millimeter-wave WLAN system were analyzed,and then we proposed a IEEE 802.11aj SC millimeter wave ultra-high speed WLAN prototype design scheme,which implemented based on the NI-PXIe millimeter wave platform using LabVIEW language.The system based on IEEE 802.11 aj baseband processing included scrambling and descrambling,channel coding and decoding,constellation mapping and demapping,Fast Fourier Transform (FFT) and IFFT,synchronization,channel estimation and equalization,phase compensation and other modules.Among those modules synchronization and equalization were introduced in detail.The equalization module adopted the method of fractional-space frequency domain equalization to improve the system performance effectively.WDP (Wide Data Path) data structure was used in base-band data processing for parallel processing,effectively reducing the requirement of FPGA clock rate.The system supports a variety of modulation methods.Testing results showed that the prototype had good feasibility and applicability,which could achieve well collected of data constellation point,low bit error rate,high real-time transmission rate,as well as supporting the high-definition video stable and real-time transmission.
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