Survey of Digital Filters for Speech Signals Using Multi-Rate Signal Processing

Digital filters provide an important role in the world of communication. This paper proposes a literature review related to design the digital filters for audio application using multi rate signal processing. One of the important applications in multi rate signal processing is sub band coding. Humming sounds are present in the speech signal which cannot be removed easily and without filtering can cause degradation in the signal due to aliasing. These problems can be overcome by designing sub-band coding system and implementing digital filters such as FIR and IIR filters. The main objective of this survey paper is to analyse various techniques for designing digital filters. The focus is put on sub band coding, design of FIR and IIR filters, various transforms and quantization. The paper is concluded with a brief discussion of choosing the most appropriate digital filter for multi rate digital signal processing. Keywords—Digital filters, Multi rate Signal Processing, Sub Band Coding, FIR, IIR, Transforms, Quantization