New concept of digital multi-frequency receiver

A new algorithm of multi-frequency signal receiver is proposed. The algorithm is based on Itakura´s idea of line spectrum representation of signal spectrum derived from linear predictive analysis. The receiver has many advantages, above all, easy implementation by micro-processors, sure safe guard against miss-operations by speech and low 4 kHz. sampling is preferable than normal 8 kHz. The reciever becomes simple and practical for PB signals. Because signals are consisted of two sinusoidals and each of which is selected from low and high frequency band respectively. Further improvement of the method is carried out for micro-processor implementation by introducing WFT algorithm instead of FFT algorithm in spectrum analysis in order to reduce the number of calculation steps especially multiplications.