Abstract: A pass band flatness correction circuit for improving flatness of a ripple occurring within a pass band in a band pass filter and a mobile telecommunication repeater system is provided. The pass band flatness correction circuit includes a complementary band pass filter having a pass band transfer characteristic producing a counter-ripple of a reverse shape to a ripple in a pass band of a main band pass filter, for flattening a total of pass band transfer characteristics of a filtering system, an amplifier circuit for enhancing an increase in a filter insertion loss, and an attenuator circuit for enhancing a reflection loss characteristic of the whole circuit. The flatness and a stop band attenuation characteristic of the band pass filter whose pass band flatness is distorted and a repeater system employing the band pass filter is enhanced, to thereby improve performance and speech quality of a mobile telecommunication service.

Abstract: A pass band flatness correction circuit for improving flatness of a ripple occurring within a pass band in a band pass filter and a mobile telecommunication repeater system is provided. The pass band flatness correction circuit includes a complementary band pass filter having a pass band transfer characteristic producing a counter-ripple of a reverse shape to a ripple in a pass band of a main band pass filter, for flattening a total of pass band transfer characteristics of a filtering system, an amplifier circuit for enhancing an increase in a filter insertion loss, and an attenuator circuit for enhancing a reflection loss characteristic of the whole circuit. The flatness and a stop band attenuation characteristic of the band pass filter whose pass band flatness is distorted and a repeater system employing the band pass filter is enhanced, to thereby improve performance and speech quality of a mobile telecommunication service.