Eric Jacobsen's Professional and Technology Page

Signal Processing and Communications Engineering

I'm Eric Jacobsen and I've worked professionally as an Electrical Engineer since 1985 in the areas of Digital Signal Processing and Communications. My experience includes system engineering, research, algorithm development, standard development, technical due diligence for capital investment, patent matters, design, implementation, debug, and troubleshooting. My primary area of expertise is Wireless Communications and I served as a voting member in both the IEEE 802.16 (aka WiMAX) and IEEE 802.11 (aka WiFi) Working Groups.


This page is a repository for professional and technical information related to my work in the Signal Processing and Digital Communications areas -- a placeholder for relevant technical references and a sort of quick web resume of research and work I've been involved with. If you have a need for any of the technical information included here please help yourself to it. If you need help in these areas, I am available for independent consulting. You can be reach me at

eric.jacobsen@ieee.org

My LinkedIn profile.





Published Work, Papers, etc.

Frequency Estimation

This work was done in the context of quickly and accurately computing frequency offsets for burst communication systems. The resulting algorithm and analysis is generalized and applicable to a much wider range of applications. The original work on frequency estimation, which evolved a bit over time, can be seen here (which includes a link to a pdf file of the paper, On Local Interpolation of DFT Outputs). It led to follow-up work comparing additional, similar algorithms here. Matlab source code for the comparison simulations is included on the follow up page. The basic frequency estimator and the comparison studies were published in the IEEE Signal Processing Magazine (May, 2007, p.123) and are also covered in more detail as Chapter 10 of Rick Lyons' Streamlining Digital Signal Processing.

Sliding-Window DFT Algorithm

I also wrote Chapter 14 of Streamlining Digital Signal Processing which covers the Sliding Window DFT. This chapter was also based on an article I'd done (with Rick Lyons) in IEEE Signal Processing Magazine.

Signal Propagation and Channel Model Research

While working at Intel in the Radio Communications Laboratory I was Principal Investigator on several research projects, one of which included propagation studies in the 5GHz band. This work led up to the high-throughput studies that eventually became the IEEE 802.11n standard amendment. The 5GHz unlicensed bands provide much more spectrum than is available in the 2.4GHz unlicensed ISM band, and there's less interference. While there were a number of good propagation studies in the 2.4GHz band there was very little data to support model development for 5GHz applications. We developed a test apparatus and did extensive measurements at a number of residential (basically the team member's homes) and office sites.

When we were done with the data collection we had an enormous database of channel measurements. Val Rhodes spent a ton of time on data mining and crunching and at the end we had some interesting insights and some new pathloss models. Since Val did most of the number crunching he was primary author on the paper, Rhodes and Jacobsen - Stationary Propagation Characteristics for 5GHz Wireless LAN Applications. (pdf) The pathloss results were used in the development of the IEEE 802.11n Channel Models.

An overview of Intel's research leading into the development of IEEE 802.11n

Intel Technology Journal, Vol. 7, Issue 3 (pdf) contains an article (p. 47) titled High-Throughput Wireless LAN Air Interface which summarized some of the research we'd been doing at the time (2003). Again, the idea was to prime the technology pipeline for the expected work on high-throughput WLAN in the IEEE 802 group, which ultimately became IEEE 802.11n. I'd been working primarily on the Adaptive Bit Loading (ABL) techniques described as well as the Advanced Forward Error Correction work on Low Density Parity Check codes. The MIMO techniques adopted in the IEEE flatten the channel enough that ABL wasn't worth pursuing, but LDPC codes are included in the standard as an option. I chaired the ad-hoc committees that developed the LDPC codes for IEEE 802.16e (aka WiMAX) as well as the TGnSync proposal effort in IEEE 802.11n that developed the LDPC architecture adopted there.

My professional blog.

I occassionally write about DSP and Digital Communications topics in my blog at DSPRelated.


Intellectual Property

I am an inventor on a number of US and foreign patents. (Fifteen at last count.)

While working at Intel I served on some of the various incarnations of Intel's Wireless Patent Committee. Intel has some outstanding IP attorneys and I learned a lot about patents, patent policy, and related issues.


Technical Due Diligence for Capital Investment

I've done an extensive amount of Technical Due Diligence for capital investment, the majority of it for Intel Capital while I was in the Radio Communications Lab. From 1999 to about 2004 there was so much activity that I long ago lost count of how many companies we looked at. My involvement has been primarily with companies in wireless communications with example technologies including smart antennas, WAN, wireless networking, physical layer advancements, coding, and RFID.


Summary of Expertise

If you need help in any of the following areas I am available for consultation:


My LinkedIn profile.

Contact me at

eric.jacobsen@ieee.org

Copyright 2008, Eric Jacobsen.

Last modified August 14, 2008, although all I changed was this date.

The background image of Kokopelli blowing a sinx/x waveform out of his flute is an attempt at faking a glyph showing my interests in southwestern anthropology, signal processing, and music. It seemed like a cool idea.