Flexible Biometric Online Speaker-Verification System Implemented on FPGA Using Vector Floating-Point Units

This paper presents the implementation of a speaker-verification system on field programmable gate array. The algorithm is executed by software over an embedded system that includes a MicroBlaze microprocessor connected to a vector floating-point unit (VFPU). The VFPU is designed to speed up the resolution of any vector floating-point operation involved in the verification algorithm, whereas the microprocessor manages the control of the process and executes the rest of operations. With a clock frequency of 40 MHz, the system is capable of executing the complete algorithm in real time, processing a voice frame in 9.1 ms. The same verification process was carried out for two different systems: 1) an ARM Cortex A8 microprocessor; and 2) configuring MicroBlaze with the scalar floating-point unit provided by Xilinx. The experimental results show that when comparing our proposed system against both systems, the number of clock cycles is reduced by a factor of 11.2× and 15.4×, respectively. The main advantage of the VFPU is its flexibility, which allows quick adaptation of the software to the potential changes produced in both the system and the user requirements. The algorithm was tested over a public database that contains the utterances of different users acquired under different environmental conditions, providing good recognition rates.