一种数字中频系统的设计

Design of a Digital Intermediate Frequency System

随着高性能的模/数、数/模转换器件(ADC、DAC)和现场可编程门阵列(FPGA)的出现,基于软件无线电(SDR)的数字中频技术被广泛地应用到3G直放站中.在分析了WCDMA直放站中频单元基本原理和结构的基础上,比较了模拟处理和数字处理的优劣,提出了一种数字中频系统的设计,并对其中的关键技术,如采样率的选择、滤波器的设计等进行了具体阐述.

As the emerging of high performance Analog-to-Digital Converter. Digital-to-Analog Converter （ADC.DAC） and field programmable gate array （FPGA） , the software defined radio （SDR） based Digital IF technology has been widely used in 3G repeater. Based on the analysis of the principle and structure of Digital IF module in the WCDMA repeater, this paper presents a design of the Digital IF system compared with the method of signal-processing in analog, and shows the key technologies such as the selection of sampling-rate and the design of FIR filter in the Digital IF system.