Adaptive rate conversion filter

Achieving an appropriate rate conversion is a key factor in digital signal processing. In ordinary applications, a conversion ratio is expressed by a simple fraction. Therefore, the rate conversion can be performed by simple hardware. However, if this conversion ratio is time-variant or if it cannot be expressed by a fraction, very complicated and sophisticated hardware is required, using the present techniques. This paper discloses, a new rate conversion algorithm for those conversion ratio conditions. This algorithm reduces the hardware requirement drastically, compared with conventional methods. Validity and usefullness are proven by applying this algorithm to a parallel transmission digital radio demodulator attached to the output from an FFT digital filter bank.