Abstract

The design and implementation of a new method of generating arbitrary signals was attempted. This new system is based upon the use of Walsh functions, which are derived from Rademacher functions. The VHDL modeling and the Xilinx field programmable gate arrays (FPGA) implementation of the proposed circuit were made. Two Walsh circuits realized using counter and exclusive OR (XOR) gates mainly control the operation of the system. For area efficiency, suitable word lengths at every stage were designed accurately based on arithmetic rules and Matlab analysis. The implementation was targeted to 3 technologies from Xilinx - Spartan 3, Virtex E and Virtex 4. It was found that the proposed system is about two times faster than the previously reported designs. In addition, the occupied area in some cases is less than 25% of the earlier designs.

Key words: Arbitrary waveform generation, Walsh functions, Rademacher functions, Walsh Circuit, VHDL Model.