Digital signal processing is better than analog signal processing for several reasons. Early radar systems during WWII used analog processing and encountered many problems with aging, stability, and sensitivity. By the 1950s, digital signal processing was established and provided guaranteed accuracy and perfect reproducibility. Applications of digital signal processing now include audio, automotive, medical, military, telecommunications, video and imaging, and wireless communications. Digital systems have perfectly reproducible performance without aging or environmental sensitivity issues faced by analog systems. The use of digital signal processing for problems involving signals is recommended.

1. Kevin Kuang © 2004
Use Digital Signal Processing
instead of Analog Signal Processing

2. Kevin kuang © 2004
First signal processing problem
 World War II brought us Radio Detection And Ranging (RADAR)
- one of the first signal processing applications
- it was implemented in analog
- encounter lots of problem, aging, stability, sensitivity…
 By 1955 control theory was established due to the mathematics
explaining:
- the effects of sampling
- its spectral effects
- the z-transform

3. Kevin kuang © 2004
Prophets
 “Thus, although many signal processing will be most
economically implemented with analog methods, it is the
capability of digital system to achieve a guaranteed accuracy
and essentially perfect reproducibility that is so appealing to
engineers. … To summarize, the importance of the DSP should
eventually surpass that of analog signal processing for the same
reasons that digital computers have surpassed analog
computers.”
- p5, “Theory and Application of Digital Signal Processing” Prentice Hall, 1975,
Lawrence Rabiner and Bernard Gold

4. Kevin kuang © 2004
Digital better than Analog
 Analog
- Aging
- Sensitivity to the environment
- Uncertain performance in production units
- Variation in performance of units
- Sensitivity analog traces on PCBs
- Effort to migrate and adopt “canned” solutions
 DSP doesn’t have these problems!

5. Kevin kuang © 2004
Applications
 Audio (sound card, digital musical instruments)
 Automotive (Security Systems, Safety Systems)
 Medical (Medical Imaging, Personal Medical Devices)

Military (Data Communications, Radar/Sonar)
 Telecom (Navigation Systems, Telecom Accessories)
 Video and imaging ( Digital Still Cameras, Digital TV)
 Wireless communication (cell phone, Bluetooth Solutions)

6. Kevin kuang © 2004
Summary
 Digital system has perfectly reproducible and never varying
performance.
 Applications already became everywhere, and more will come.
 For any signal problems, think about digital first!

7. Kevin kuang © 2004
Summary
 Digital system has perfectly reproducible and never varying
performance.
 Applications already became everywhere, and more will come.
 For any signal problems, think about digital first!