增量调制DFT的硬件实现

HARDWARSE IMPLEMENTAION OF DFT BASED ON DM

作者在文献[1,2]中提出过一种基于 DM(LDM 和 ADM)序列的 DFT 实现方法,与常规的 PCM 处理方法相比较,它不需要使用模数变换器和乘法器,从而简化了硬件设备量,降低了成本,而其信噪比与 PCM 处理结果相一致。本文在笔者以前研究的模拟分析基础上用硬件实现基于 DM的 DFT 实时处理。文中采用 ROM 来存贮各个系数值。本法具有速度快、硬件结构简单的特点,但由于ROM 存取速度的限制,目前还只能用于对语音、地震等信号的处理。

A hardware implementation of Discrete Fourier Transform(DFT)ispresented using Delta Modulation(DM)technique based on a realization method pro-posed by the author in references.With this implementation,the hardware ismuch different from the eonventional implementation and is constructed without A/Dconverter and multiplier,so that it is simpler and of lower cost.Its SNR is approximatelythe same as that of conventional one.EP ROM is used to store all the coefficients.Thefeatures of the method presented are fast in operation and simrle in structure.Due to thelimitation of the speed of ROM's operations,it is now only suitable for processing nar-row fand signals,such as speech signals or seismic signals.