Simplified spectral analysis system using phases

摘要

The system has at its input a Cartesian-to-polar coordinate transformer RP receiving the binary variables Xn and Yn representing the real and imaginary parts respectively of the nth sample of the received signal. This is followed by a binary rearrangement device RB supplying a binary number PHI n = RnSnTn "proportional" to the phase of the received signal. Phase combinations of the type e<j PHI >n.e<-2 pi j>kn/N occurring in the expression for the discrete Fourier transform of dimension N are then produced by a set of standard binary subtractors AD0 - AD7. After a polar-to-Cartesian coordinate transformation in polar-to-Cartesian coordinate transformers in coordinate transformers PR0 - PR7, the signals supplied are summed in adders SIGMA 0 - SIGMA 7. The modulus ¦Ai¦ of the spectral lines supplied can then be calculated by simplified modulus calculators CM0 - CM7. The system includes only standard logic devices. Application to Fourier transform calculators. <IMAGE>