4G 无线通信系统通过多输入多输出(multiple input multiple output, MIMO) 技术及增加信号带宽来获得高的系统吞吐量. MIMO 的性能很大程度上取决于真实信道的传播环境，利用能模拟真实信道传播环境的信道仿真仪进行空中测试，可以在实验室环境下验证MIMO 系统性能. 为了更好地进行宽带MIMO 系统性能的测试，设计了一种针对宽带MIMO的信道仿真仪，利用压缩感知实现宽带模拟信号采样. 为降低仿真高阶MIMO时的计算复杂度，采用了频域实现方法.
4G technologies are focused on delivering high level throughput by using MIMO technology and wider signal bandwidth. To evaluate the MIMO system performance highly related to the accurate representation of the channel condition, over-the-air (OTA) test is performed with a channel emulator as an important part. In this paper, a channel emulator for wideband MIMO system is designed. Compressed sensing is used to sample analog signals as the bandwidth becomes wider. Frequency domain approaches are used to implement the emulator to reduce complexity for higher order arrays.
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