一种L波段数字接收机的直接射频采样研究

随着现代集成电路的发展,高速串行JESD204B协议及高速ADC令射频直接采样成为可能。本文对L波段数字接收机的直接射频采样进行研究,基于新型ADC器件AD9625,提出与支持JESD204B软核的FPGA协同工作的设计方案,在硬件设计不发生改变的条件下,分别支持在ADC内进行下变频、抽取、滤波或在FPGA内部进行此项工作。两种方式均属数字处理,在处理不同回波信号时可通过软件进行调整。

With the development of modem integrated circuits, high-sped serial protocol JESD204B and high-speed ADC make direct RF sampling possible. In this paper the L-band direct RF sampling of digital receiver is studied. Based on new devices AD9625, the design conceptual came up. The ADC collaborates with FPGA which contains JESD204B core. The DDC, decimation and FIR can operate either in ADC or in FPGA without any change on the hardware. Both methods belong to the digital processing. It can be adjusted by software when deal with differential RF echo.