These advantages translate into lower cost and are the main reason for the ongoing shift from analog to digital processing in wireless telephones, consumer electronics, industrial controllers, and numerous other applications.
In order to store, transmit, or process analog signals using digital hardware, first analog signals must be converted into a digital signals by sampling and quantization. In this respect, the term digital signals refers to signals that have been conditioned and formatted into digits. Examples of digital signals include data transmitted over local area network (LANs) or other high-speed networks. Digital Signal Processors (DSPs) are found in a wide range of applications such as in communications, servo and motor control, speech and video processing. Today, DSPs are used in ECG (electro cardiogram) monitors, Fax, modems, cellular phones, digital answering machines, feature phones, and digital cameras to name just a few.
A complete signal processing system usually consists of several components for signal conditioning and incorporates multiple signal processing techniques. In some cases, for example, it may be desirable to reformat the information contained in a signal. This would be the case in the transmission of voice signal over a frequency division multiple access (FDMA) telephone system. In this case, analog techniques are used to ßtack" voice channels in the frequency spectrum for transmission via microwave relay, coaxial cable, or fiber.
In other cases, the signal containing the information is buried in noise, and the primary objective may be the signal recovery. Techniques such as filtering, auto-correlation, and convolution, are often used to accomplish this type of processing.
Yet another requirement for signal processing may be to compress the frequency content of the signal (without losing significant information) and then format and transmit the information at lower data rates, thereby achieving a reduction in required channel bandwidth. High speed modems and adaptive pulse code modulation systems (ADPCM) make extensive use of data reduction algorithms, as do mobile radio systems, MPEG recording and playback, and High Definition Television (HDTV).
Topics in digital signal processing [2], [3] include a number of specific techniques. These techniques can be roughly categorized into two families:
A Digital Signal Processing platform provides an economical way to introduce algorithms and techniques for real-time digital signal processing to computer science students. In a typical development environment, the platform is connected to a host computer thru a parallel port. Once the program is compiled, linked, debugged simulated and tuned for performance it is loaded on to the DSP with the emulator software. From thereon the module functions as an embedded signal processing system.
Thru the Motorola University Program, I have obtained the core hardware components for building a design and test platform. The main hardware components include (i) a Motorola DSP56824 16-bit processor, and (ii) coder-decoder chip for conversion of voice signal to digital signal. On the software side, I have obtained from Metroworks Inc. an Integrated Development Environment (IDE). The IDE software includes: C language compiler, linker, loader, debugger, simulator, and emulator tools for the DSP56824 processor. The software is, however, provided for a trial period of one month. Using the software environment IDE, I have successfully programmed the DSP56824 signal processor for filtering out background noise from voice signals.
The funds from Cayhill award will be used (i) to purchase the IDE software when the trial period expires in November 2000, for continued development of more applications in voice processing and (ii) to add real-time video processing capabilities.
After several applications in audio and video processing are successfully built with the design platform, a grant proposal will be submitted to NSF during Fall 2001 to fund the establishment of a Digital Signal Processing Laboratory (DSP Lab). The DSP Lab will be used to support research and instruction in the fast growing fields of embedded systems, image processing, and voice processing.
| SN | Software, Hardware | Vendor | Price |
| 1. | Integrated Development Environment (IDE) | Metroworks CodeWarrior | 200.00 |
| 2. | Charged Couple Device (CCD) Camera | Analog Devices | 450.00 |
| 3. | Video Encoder, and Decoder | Analog Devices | 250.00 |
| 4. | Video Processing Software libraries | Hyperception | 2500.00 |
| 5. | Video Monitor | Analog Devices | 250.00 |
| Total* | 3650.00 |
*The Computer Science Department has agreed to provide matching funds for up to $ 1000.00 towards the cost of this project.
I. Publications:
``Parallel Algorithms for k-tree recognition and its
applications'',
HICSS-27, 27th Hawaii International
Conference on System Sciences, 1994. jointly with Shietung Peng.
``Mixed Domination in trees- A Parallel Algorithm'',
Congressus Numerantium, vol. 100-104, 1994, jointly
with Shietung Peng.
``Parallel Algorithms for Finding Connected, Independent, and Total Domination in Interval Graphs'', Parallel Algorithms and VLSI Architectures, June 1991, Elsevier Publications, jointly with Shietung Peng.
``Parallel Algorithms for Cographs and Parity Graphs with Applications'', Journal of Algorithms, Vol. 11, 1990, pp 252-284, jointly with Shietung Peng.
``Parallel Algorithm for Maximum Matching in Cographs,''
Congressus Numerantium, Vol.77, December 1990, pp
217-227, jointly with Shietung Peng.
``Parallel Algorithm for Cographs: Recognition and
Applications'',
Springer Verlag Series- Lecture Notes
in Computer Science, 1989, jointly with Shietung Peng.
``Parallel Algorithms for Complement Reducible Graphs and Parity
Graphs'',
Proceedings of the International
Conference on Computing
and Information, May 1989,
jointly with Shietung Peng.
``Parallel Algorithms for Path Covering, Hamiltonian Paths, Hamiltonian Cycles Cograph'', 1990 International Conference on Parallel Processing, Vol.3 1990, 364-365, jointly with Shietung Peng.
II. Invited Lectures :
III. Membership in professional societies: