A NEW MULTIPLIER-FREE STRUCTURE FOR DFT BASED ON DELTA MODULATION
一种不用乘法器的增量调制DFT新结构

A new implementation of the DFT based on delta modulation (DM) is proposed. It is different from the conventional implementation based on PCM. The hardware structure of the method is constructed without A/D converter and multiplier, so it is simpler and of lower cost. Its SNR can approach that of the conventional one, such as FFT. Computer simulations demonstrate that for deterministic signals, results obtained agree well with theoretical analyses, for band-limited Gaussian signals; if step size is suitably selected, results similar to the conventional DFT can still be obtained. Because of the limitation of the working speed of the device, this method will be suitable for processing speech and seismic signals. Finally, the hardware structure which simply consists of a ROM, an adder and some other auxiliary circuits is given.