Research On Speech Localization Technology Based On Microphone Array On A Mobile Robot

With the rapid development of computer technology, speech localization is a new project. In complex environment, such as poor light or obstructions, locating the interesting sound source, and even tracking the target sound source, which make speech localization technology used widely. Now, the most research on speech localization technology is still in the theoretical simulation stage. Speech localization research is difficult in reasonable choice of the localization algorithm, topological structures of microphone array, reducing the surrounding environmental noise, and so on. Speech localization technology has become focus in the world because of broad application foreground.Aiming at the above requirements, speech localization system is designed based on microphone array on a mobile robot, by the use of microphone array to pick up sound source signal, the signal analysis based on pre-treatment such as filtering, amplification, endpoint detection and so on. SEM / ADT800 multi-channel data acquisition card based on PC/104 is applied for the speech signal acquisition and processing. Based on analysis and comparation of the traditional orientation algorithm, this paper employs generalized cross-correlation time delay estimation algorithm to calculate the time difference between the microphone array element, interpolates generalized cross-correlation function, weights PHAT, removals pseudo-zero cross-correlation function peak, as well as narrows the search interval and other improvements, makes the simulation algorithm and analyzes the accuracy of algorithm. Four-element cross Lineup geometric positioning is used to caculate the sound source signal target location and orientation. According to actual demand, it focuses on improving performance of the algorithm and the accuracy of orientation system, and proposing the entire orientation process of algorithm.On the base of theory analysis, this paper configures microphone array, designs and realizes the pre-filter-amplifier, builds the system working environment, edits pre-processing program, speech data acquisition program and speech localization program. Then, it tests the speech localization system, gives the experiment results, analyzes the error, and suggests to improve the accuracy of the speech localization system.The experiment proved that speech localization system based on microphone array on a mobile robot is actually available, with good performance, and is able to control the system error in the required range.