Exp-10 DSP Application

The last experiment was based on a application of signal processing. The signal had to be a one-dimensional signal. This was a group experiment. We had to find patents and ieee papers related to a single application. We were thinking about a audio processing application and after some research we came up with comb filter for noise cancellation.

My group members: Umesh Gawale, Pranav Ghaisas, Tejashree Gore, Natasha Choudhary

Application: Noise Cancellation using Comb Filter

The patents of group were:-

1. Adaptive Frame Comb Filter System

2. Inverse hyperbolic comb filter 

3. Comb Filter

4.Speech signal processor using comb filter

My patent was : Inverse hyperbolic comb filter 

Patent No:- US5270803 

Review:

The patent describes an inverse hyperbolic comb filter. It decodes an encoded signal by subtracting a vertically filtered and horizontally filtered version of the encoded signal from a delayed version of the encoded signal. The output is further horizontally filtered. This gives first output. Later, a twice delayed version has the first output signal subtracted  there from to provide a second output.The inverse hyperbolic comb filter may be used in encoding signals where input signal components are first filtered through respective inverse hyperbolic comb filters to provide filtered component signals which are then provided to a combiner to generate an encoded output signal.With simple comb filters, cross luminance artifacts may result due to high frequecny chroma. Another drawback is loss of high frequency luma resolution of reference points near the innermost corner areas which may give rise to cross-artifacts.

The IEEE paper reviewed was titiled 'New Method of FIR comb Filtering'.In this paper, it is mathematically proven that FFT comb filter can be transformed to a computational efficient equivalent structure. It is also shown this structure can be used as simple FIR filter. The FIR filter removes statbility issues and proper choice of m(radix2) allows FIR filter wih no multiplications avoiding all quantization issues.

https://drive.google.com/open?id=0Bzfvoo_rjoa8S19TN2V1SE9kckk