The Researches And Design Of A IF Digital Receiver

Conventional receiver depends on hardware much more and the sign's adaptability is bad. The emergence of software radio results in receiver's renovation. The foundational idea of Software Radio ( SWR) is to establish a open, standard and modular universal hardware platform where the A / D converter is moved as closed as possible to antenna and all of the communication function is realized by software. Due to the limitation of device level ,it is impossible to sample RF signal in direct now and have to choose the middle project—sampling IF signal, using special chip to build in the flexible multi-mode and multi-function receivers.The study of this paper places emphasis on the block of signal processing in the IF and the block of base signal processing, and gives special details of algorithm analysis and realized techniques in ADC, DDC and DSP. In this paper, a programmable digital down converter applied on wide bandwidth digital IF receiver is designed and implemented by FPGA. This PDDC can translate digital IF signal channel shape. It establishes an digital IF Software Radio framework.Because of the opening of software radio, bus architecture is usually adopted. Absorbed the idea of virtual radio, the designed IF digital receiver is based on PCI bus. Date after AD sampling and digital down converter transfer to computer through PCI bus. The design based-on PCI bus updates software and hardware handily, economizes cost.