# coefficient quantization in fir filter

We have concentrated on effects due to coefficient quantization on filter response and in that also on IIR filters. Quantization has no effect on them. 19. Good for interpolation, decimation filtering Wonyong Sung Multimedia Systems Lab SNU. FIR Filters With this chapter we turn to systems as opposed to sig-nals. 18. Though any number of quantization levels is possible, common word-lengths are 8-bit (256 levels), 16-bit (65,536 levels) and 24-bit (16.8 million levels). The filter is a fractional delay filter (FIR), so for very small fractional delays some of the coefficients are very small, while the center tap is large. > The noise added in each multiplication will be filtered of the rest > of the taps in the filter. The systems discussed in this chapter are finite impulse response (FIR) digital filters. ANSWER: (b) 12 to 14. The previous article in this series discussed some basic structures to implement Finite Impulse Response (FIR) filters. coefficient quantization. The problem is that the output is about five times lower in magnitude. Accordingly, if your filter's coefficients are always quantized to 14 bits, you can expect the minimum stopband attenuation to be only around 70 dB. Th e effects of fixed-point . However, it may be the case that coefficient quantization changes your filter's ferquency response enough so that more SIGNAL NOISE gets through the filter than you expected. Magnitude Response. One consideration for choosing the appropriate structure is the sensitivity to coefficient quantization. \n In digital filters, both the data at various places in the\n filter, which are continually varying, and the coefficients, which\n are fixed, must be quantized. The FIR filter system of claim 16, said multiplier comprising a hardware multiplier. Quantization does not affect the phase characteristics of FIR filter, but it affects the magnitude response. This is in contrast to infinite impulse response (IIR) filters, which may have internal feedback and may continue to respond indefinitely (usually decaying). quantization noise, while minimizing hardware cost and power consumption . – Digital filter coefficient precision rule-of-thumb: 6dB/bit – 135 / 6 = 22.5 …round to 24b FIR filter coefficients • 135dB of stopband attenuation results in negligible aliased non-tonal quantization noise • Where should the stopband begin? If in doubt, try them all, that's what computers are good at. 5 to 10 b. Phase Characteristics. The system where the filter is to be implemented is a 16 bit twos complement system, both input and output should be that, too. Lastly, there is some IMPLEMENTATION NOISE introduced by the filter implementation, as I discused above. DOI: 10.1016/j.dsp.2012.09.020 Corpus ID: 3498803. Home >> Category >> Electronic Engineering (MCQ) questions & answers >> Digital Signal Processing; Q. If FIR filter are realized using direct from realization then linear phase is maintained even when the quantization of filter co- efficients is done. In section III, details ECG signal are described. Coefficient quantization (limited-precision coefficients) will result in filter pole and zero shifting on the z-plane, and a frequency magnitude response that may not meet our requirements. The effects of quantization on data\n and coefficients are quite different, so they are analyzed\n separately.\n \n Data Quantization \n The authors im plement the . receiver are discussed in . Ideal FIR Coefficient Quantization There exists methods for designing ideally quantized-coeffi-cient PFPs  and PPFDs  that function exactly correctly in short word length environments. In this paper, we implemented multiplierless FIR filter with and without optimized coefficients and their performances are compared in terms of speed, power, and area.