Speech Recognition System HM2007

The speech recognition system HM2007 designed as a completely assembled and easy-to-use programmable speech recognition circuit. Here Programmable means that you can train the words (or vocal utterances) you want the circuit to recognize. This module comes with an 8-bit data out and can be interfaced with any microcontroller for further development. These HM2007 widely used in applications such as controlling home appliances, robotics movements, Speech Assisted technologies, Speech to text translation.

HM2007 designed as a CMOS voice recognition LSI (Large Scale Integration) circuit with an analog front end, voice analysis, regulation, and system control functions.  This HM2007 chip is capable of providing options of recognizing either the .96 second word length (40-word vocabulary). Or the 1.92-second word length (20-word vocabulary). The basic principle of voice recognition involves that when the speech or words spoken by any human generates vibrations in the air, known as sound waves. These continuous or analog waves further digitized, processed, and then decoded to appropriate words and then appropriate sentences.

A speech exists in the form of an acoustic waveform, i.e. signal carrying message information. A microphone converts this acoustic waveform to analog electrical signals. The Analog to Digital converter converts this analog signal to digital samples by taking precise measurements of the wave at discrete intervals. Digital Signal Processor using FFT technique converts this digitalized time-domain signals to the frequency domain. In other words, the digitized signal segmented into small parts of frequency amplitudes.  Each segment or frequency corresponds to the different sounds made by human beings.