基于FPGA的航空数据链信道模拟器

A New Channel Emulator for Aerospace Data Link Based on FPGA

针对航空通信背景,建立了航空数据链复合衰落信道模型,并提出了一种基于谐波叠加思想且易于FPGA硬件实现的定点模型。该模型利用不同谐波叠加产生高斯随机过程,并通过非线性变换分别获得Nakagami衰落和对数正态分布衰落。最后,通过数值仿真选取合适的定点参数,并利用Xilinx公司的FPGA芯片进行编程实现。实测结果表明,该硬件模拟器的输出衰落统计特性与理论值吻合,可用于实际航空数据链系统的模拟测试。

Considering the aeronautical communication scenario, a new composite fading channel model for the aerospace data link system is established in this paper.And on this basis, a fixed-point realizable model based on Sum-of-Sinusoids （SoS） method is proposed which is easy to be achieved by FPGA.It generates Gaussian random processes using different SoS models and then obtains the Nakaga-mi fading process and lognormal fading process through some nonlinear transformations.Finally, the suitable fixed-point parameters are selected by numerical simulation and implemented based on FPGA produced by Xilinx.The experimental results show that the statistical characteristics of this channel em-ulator are consistent with the theoretical value, and it can be used for the test of aerospace data link sys-tem.