Software-defined radios (SDR) are highly configurable hardware platforms that provide the technology for realizing the rapidly expanding third (and future) generation digital wireless communication infrastructure. While there are a plethora of silicon alternatives available for implementing the various functions in an SDR, field programmable gate arrays (FPGAs) are an attractive option for many of these. This paper will describe how many of the functions required in a software radio system can be realized in an FPGA. Topics discussed will include adaptive channel equalizers and channelization functions.