The digital front-end of software radio terminals

When expanding digital signal processing of mobile communications terminals toward the antenna while making the terminal more wideband in order to be able to cope with different mobile communications standards in a software-r adio-based terminal, the designer is faced with strong requirements such as bandwidth and dynamic range. Many publications claim that only reconfigura ble hardware such as FPGAs can simultaneously cope with such diversity and requirements. Starting with considerations of the receiver architecture, we describe key functionalities of the digital front-end and highlight how si gnal characteristics of mobile communications signals and commonalities amo ng different signal processing operations can be exploited to great advanta ge, eventually enabling implementations on an ASIC that, although not recon figurable, would empower the software radio concept.