多通道频率交织1.4GHz宽带DRFM系统

1.4 GHz Broadband DRFM System Based on Multi-Channel Frequency Interleaved

更大的带宽是数字射频存储(DRFM)系统的发展方向,获取超宽带微波器件、高速AD/DA、高速存储/信号处理芯片等关键器件成为制约DRFM系统发展的瓶颈问题。该文提出了一种多通道频率交织架构,构建了一套C波段的超宽带DRFM系统。并针对系统复杂度增加带来的信号失真问题,在FPGA上设计并实现了补偿算法。实验结果表明:系统瞬时带宽达到f0±700 MHz、带内幅度平坦度优于6 d B、信号线性度优于5×10?5。从而实现利用通用器件构建超大带宽DRFM系统的目的。

Large broadband is an important goal of the digital radio frequency memory （DRFM） system, but a bottleneck problem is how to obtain wideband RF microwave devices, high speed AD/DA, memory and signal process chip economically and efficiently. To avoid this problem, a novel DRFM system based on multi-channel frequency interleaved method has been developed. The design of the digital correlation algorithm can overcome the shortcomings of this system on reconstruction accuracy, such as the channel amplitude and phase distortion, the difference of delay between channels, and the non-ideal effect of sharp bandpass filters. Test experiments certify that the system can reconstruct the broadband signal f0±700 MHz with the flatness less than 6 dB and the linearity less than 5× 10^-5.