Apparatus and method for improving the voice quality in portable communication system

PURPOSE: An apparatus for improving a communication quality in a portable terminal and method thereof are provided to improve reception rates by accurately receiving a voice signal. CONSTITUTION: An input unit(100) receives the input of a voice signal. An expansion signal generation unit(112) creates a harmonic wave signal corresponding to a frequency band by using the voice signal inputted by the input unit. The frequency band displays sensitive reaction for hearing. An adder(114) integrates voice signal inputted by the input unit with the created harmonic wave.