An architecture for the vlsi design of systems for time-frequency analysis and time-varying filtering

A flexible system for timefrequency signal analysis is presented. It is based on the S-method, which has a significant advantage in implementation since it can involve, as a key intermediate step, the Shorttime Fourier transform or the Hartley transform, each widely studied and commonly used in practice. Signal invariant and signal dependent system forms are presented. Hardware design, for a fixed-point arithmetic, is wellstructured and suitable for VLSI implementation. The same hardware, without additional time requirements, may be shared for the simultaneous realization of the fourth order LWigner distribution, as well as for the realization of the cross-terms free fourth order polynomial Wigner-Ville distribution. This possibility makes the designed hardware suitable for wide range of the applications. The proposed hardware is applied to the realization of timevarying filtering, as well. Finally, it has been implemented with FPGAs chips (Field Programable Gate Array) in order to verify the results on real devices.