A new implementation for DFT based on delta modulation

This paper proposes a new implementation for DFT based on delta modulation which is different from the conventional PCM implementation. The hardware structure of the method is multiplier-free, simple and low in cost. Theoretical analyses show that its SNR can approach conventional one's, for instance, FFT. Computer simulations demonstrate that for deterministic signals, the results agree with theoretical analyses. For bandlimited Gaussian signals, we can still get results similar to the conventional DFT's if selecting the step size suitably. A hardware structure which simply consists of ROM, an adder and other auxiliary circuits is also given. This Project is supported by the National Natural Science Fundation of China.