FDF, a 512-TAP FIR filter using a mixed temporal-frequential approach

This paper presents a newly developed chip which performs long Finite Impulse Response (FIR) filtering (up to 512 coefficients). By using an innovative architecture based on small Fast Fourier Transforms (FFT) and short FIR filters, one can achieve such a function on a single chip at a reasonable price: FDF (short for Frequency Domain Filter), 1 cm² in area with 1 million transistors, has been designed in a 3.3 V 0.5 μ triple metal level technology. The first silicon was tested in October 1994 and is fully functional up to 30 MHz at 3.3 V. Its main applications will be FIR filtering (Nyquist) and equalization of analog or digital TV signals. In particular, it should be used in the HDSAT European project for Digital TV broadcasting