The purpose of this lab is to familiarize students with the DSP development workstation in the signal processing lab by examining sampling, analysis, and reconstruction of continuous-time signals. Specifically, we will first look at sampling/reconstruction of continuous-time signals. We will then examine time- and frequency-domain displays. Finally, we will examine the importance of sampling frequency and its effects on aliasing.
Dsp workstation hardware list&Setup
Hardware: dell dimension 4550 pc with a pentium 4
microprocessor
Runs software to design/implement digital filters
Controls data acquisition and analysis
Communicates with the DSP board and/or soundcard
Edits/assembles/downloads code for the DSP chip on the DSP
board
National instruments speedy-33
A self-contained, high-performance,
programmable DSP board for signal processing applications. TheSPEEDY-33 comes equipped with a Texas Instruments DSP for high
speed DSP calculations and Analog to Digital (A/D) and Digital toAnalog (D/A) converters for interaction with the outside
world.
Specifications of the
NI SPEEDY-33 are as follows:
Eight memory-mapped LED’s and eight memory-mapped general
purpose switch inputs
Serial Port, CompactFlash interface
Condenser microphone.
Personal headphone set with individual
volume control.
Black 3 prong headphone booster.
Audio cable to go from the computer sound
card to the microphone.
Male to male adapter cable.
Alternative option to NI Speedy 33:
Texas instruments 6711 dsk
Digital Signal Processing Board with PCM3003 Audio Daughter Card
The DSP board is responsible for the
high-speed DSP calculations and the daughter card controls the A/Dand D/A conversion between the DSP board and the outside
world.
Specifications of the DSP board and daughter card are as
follows:
16-bit stereo audio codec with two on-board microphones. A
lowpass anti-aliasing filter at the input channel with a fixedcutoff frequency = 24 kHz
Software:
The software used in the lab is
National Instruments
LabVIEW DSP Module ; a block diagram-based
graphical programming package for digital signal processing thatwill be used for: data acquisition, time domain data display,
frequency domain calculation and display, filter implementation,convolution and correlation calculations, speech/signal modeling,
and real-time filtering. Using LabVIEW DSP Module in conjunctionwith the LabVIEW Digital Filter Design Toolkit, the DSP board and
the rest of the lab equipment will not only allow students toperform data acquisition, analysis, and filtering, it will also
give them the ability to listen to the filtered output.