DTMF BASED AFAAN OROMO, AMHARIC AND TIGRIGNA LANGUAGE AUTOMATED IVRS

In this paper we designed and developed Dual Tone Multi Frequency (DTMF) based Interactive Voice Response system (IVRS) for Amharic, Afaan Oromo and Tigrigna languages using low end terminal telephone line. The system is designed to help users to access list of commodity price and trade schedule information via telephone keypad input given by DTMF signal dialing to IVR application service number in reliable, scalable and user-friendly manner. To design, develop and implement the proposed system the functional requirements are described by the use case model. Based on the requirements the complexity of the proposed system is decomposed into sub systems. Voice interface subsystem is responsible for voice menu handling, DTMF input interpreting, and phone line handling. Speech synthesis subsystem responsible for synthesizing speech for dynamically changing information. To implement the proposed model open source Asterisk PBX and X lite VoIP soft phone is used. Asterisk PBX is connected to with the X lite VoIP soft phone over the local area network. User interacts to IVR application by using telephone keypad via dial plan which is configured on asterisk server by defining outgoing and incoming call flow mechanism. When messages are received on this channel to asterisk server, the message is sent to the IVR application for processing using Asterisk's Application Gateway Interface (AGI) to interact with users based on predefined IVR voice menu and synthesized speech on IVR application.