Design and Implementation of Speech Recognition on a Softcore Based Fpga

A speech recognition algorithm is implemented on a Xilinx´s MicroBlaze softcore based FPGA platform. When compared to programmable DSP or RISC processor based design, this approach not only can support large vocabulary speech recognition but also leads to a multi-channel system implementation utilizing an off-the-shelf FPGA device. The design space is explored in a few ways; firstly by configuring the datapath of the MicroBlaze softcore and secondly by adding a custom hardware block to speed up the emission probability computation. The hardware block designed for emission probability computation incorporates the BRAM where the reference data is accessed directly thereby reduces the overhead of transferring data from the processor to the hardware block