Dr. Howard Johnson is an electrical engineer, known for his consulting work and commonly referenced books on the topic of signal integrity, especially for high speed electronic circuit design.
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Johnson has significantly raised awareness of analog effects at work in high speed digital electronic systems. In modern digital systems, it is common for digital designs to be subject to analog effects, even if they operate at a relatively low clock frequency. Circuits operating at lower clock rates can behave as high speed digital systems if there is sufficient high frequency content in the signal edges (when transitioning between digital logic levels) relative to the distance traveled across a printed circuit board. As a result of improvements in semiconductor process, faster edge rates of even "low technology" electronic components can be sufficient to make the system effectively high speed and thus subject to havoc caused by unanticipated analog effects.
Johnson was also active in the development of two Institute of Electrical and Electronics Engineers (IEEE) standards that govern Ethernet, IEEE 802.3 Fast Ethernet and IEEE 802.3 Gigabit Ethernet.
Johnson earned his Bachelor of Science in Electrical Engineering (1978), Masters of Electrical Engineering (1979), and PhD (1982) from Rice University. His dissertation was titled The design of DFT algorithms.
Johnson has written three books.
Johnson also runs a monthly column at EDN (magazine), entitled Signal Integrity.
Johnson was recognized by the IEEE as an "Outstanding Contributor" to the IEEE P802.3z Gigabit Task Force."IEEE P802.3z Outstanding Contributor Awards". http://grouper.ieee.org/groups/802/3/z/public/presentations/july1998/award.html. Retrieved 2006-07-09.