Configurable logic for digital communications: some signal processing perspectives

For the past two decades software programmable digital signal processors and ASICs have provided hardware solutions for signal processing system designers. A new option has become available: field programmable gate arrays. FPGA-based DSP platforms allow the designer to realize a data path that exactly matches the required processing, while at the same time maintaining the flexibility of a software approach. This article presents an overview of some FPGA DSP applications. Several filter designs are presented, and the use of CORDIC arithmetic for constructing an FPGA carrier recovery loop is outlined. In addition to presenting design examples that can be realized using present-generation devices and tools, we take a brief look at how the dynamic reconfiguration aspect of certain FPGAs could be exploited in future-generation communication technologies.