978-1-5090-5170-0/16/$31.00 ©2016 IEEE
Implementation of Finite Impulse Response Digital
Filter in Digital Signal Processor Kit for Voice Signal
Application
Endang Djuana, Suhartati Agoes, R. Deiny Mardian, Revi Noviananda Nurmalasari
Department of Electrical Engineering, Faculty of Industrial Technology
Trisakti University, Jakarta, Indonesia
{edjuana, sagoes, deiny_wp}@trisakti.ac.id, revi.noviananda@gmail.com
Abstract— Transmission and receiving of voice signal must be
clear and understandable. To maintain the voice quality, filtering
is needed. Filtering is a part of signal processing to improve the
output signal quality. Digital filter is being used for filtering.
Finite Impulse Response (FIR) filter has many advantages such
as linear phase, stability, and minimum error caused by
quantization. In this research, a filter implementation using
digital signal processor (DSP) kit device with voice signal as input
has been done. Voice signal will experience Analog to Digital
Conversion (ADC), filtering and Digital to Analog (DAC)
processes. Filtering outputs are heard on the loudspeaker and the
graphs are shown on Matlab scope.
Keywords— voice signal, FIR digital filter, DSP kit
I. INTRODUCTION
Rapid development of technology includes digital
processing of voice signal. Voice is human common media for
communication [1]. Received voice signal must be clear.
However, signal processing stages are frequently influenced by
noise. To maintain the voice quality, filtering is needed.
Filtering is a part of signal processing which improves the
output quality [2] [3].
The most common filters being used in telecommunication
area are analog filter and digital filter. But digital filter is more
dominant [4]. This is caused by the Very Large Scale
Integration (VLSI) technology which makes smaller sized
digital filter possible, which can operate at very low frequency,
have linear phase response, insensitive to temperature and have
flexibility to change its frequency response [4]. Digital filter is
divided into two categories: Infinite Impulse Response (IIR)
and Finite Impulse Response (FIR). The division is based on its
impulse response [5]. FIR has impulse response with finite
length. FIR has several advantages such as linear phase, good
stability, and less error caused by quantization [6]. FIR digital
filter consists of four types: low pass, high pass, band pass, and
band stop.
Several investigations have been done in relation to FIR
application for voice signal processing but they are limited to
software simulation [7] [8]. While FIR digital filter using DSP
kit for voice signal as the input has not been investigated [9].
Therefore, in this research, voice signals of male and
female with age range of 22 – 28 years old are investigated.
The voices have been recorded and saved in .wav format. This
research uses Matlab and Code Composer Studio (CCS) as the
software platform. FIR digital filter are developed for four
types of filter and uses Hamming method as the windowing
method. Filtering process is implemented on DSP kit device.
The output signals are heard on the speaker and the graphs are
shown on Matlab scope. Finally, filtering outputs of four filter
types are analyzed.
II. VOICE SIGNAL
Voice signal is a signal representative of the sound. The
signal is formed from a combination of frequency, amplitude,
and phase. In time domain, voice signal is represented in the
form of voltage or current in function of time. Voice signal in
the time domain is shown in Figure 1.
Figure 1. Voice signal in time domain
While in frequency domain, voice signal is represented in
the form of amplitude and phase in frequency function. Voice
signals in frequency domain is shown in Figure 2.
Figure 2. Voice signal in frequency domain