正交频分复用技术由于具有频带利用率高和抗多径干扰能力强等优点,近年来在无线音频广播、无线视频广播、无线局域网等方面得到广泛的应用.然而,对OFDM系统进行准确的信道估计一直是其技术难点之一;加之MIMO技术虽然能有效的提高系统容量,但是同时也大大提高了系统的复杂度,这就进一步加大了对MIMO-OFDM系统进行信道估计的难度.在前人工作的基础上,对目前各常用信道评估方法实现复杂度与准确度进行分析,经过模拟仿真选择最适宜MIMO-OFDM系统评估手段进行研究.同时,由于OFDM系统本身对于信号同步性与正交性的苛刻要求,尤其在高容量高速率的实际应用中,其硬件实现往往需要付出高昂的成本代价;拟通过另一角度,研究在低成本、允许一定系统延迟、相对系统容量较低、传输速度不高的应用中,例如:短信业务、同区域语言服务等,仅搭建相应的软件平台实现真实仿真.%Orthogonal frequency division multiplexing (OFDM) technology has been widely applied in wireless audio and video broadcasts and WLAN due to its advantages of high band frequency usage and strong capability in anti-multipath interference. However, it is always one of the technical difficulties of OFDM that to make accurate channel estimation on the system. Moreover, though multi-input and multi-output (MIMO) technology can effectually increase system capacity, but it also greatly adds system' s complexity at the same time, and this further enlarges the difficulty in estimating the MIMO-OFDM system channels. On the basis of previous work, in the paper we carry out the analyses on the implementation complexity and accuracy of the channel estimation methods commonly used at present, and choose the most appropriate estimation means of MIMO-OFDM system through simulation for studying. Meanwhile, since OFDM system itself has demanding requirements on signal synchronisation and orthogonality, particularly in practical applications with high capacity and high rate, the realisation of its hardware usually has to cost hugely; In the paper, we try to study from another perspective to realise actual simulation by just construct corresponding software platform in applications with low cost, certain system latency allowance, relative low system capacity and medium transmission speed, such as text message business and voice services within same region, etc.
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