A Lightweight Approach to Wireless Access Point Geolocation

Submitted by Brad Tombaugh on 17 July 2010 - 11:38am


One of the side-effects of "wardriving" to detect the locations of wireless access point (WAP) using a mobile device such as a laptop computer with a GPS is that all of the locations of the WiFi hotspots all appear on a map at the location where they were detected, not where the source of the radio signal originates. This generally means that all of the mapped locations of detected networks are marked in the middle of a street.


The geographic location of a wireless access point (WAP) can be approximated by recording the GPS coordinates and signal strength in three or more locations. The point of origin can then be calculated using trilateration.

To optimize efficiency for use with a mobile device such as a smartphone, use of a simple algorythm to capture four points, corresponding to the minimum and maximum latitude and longitude coordinates where the signal from the WAP can be conveniently measured.

Watch "The Pluto Files" on PBS tonight!

Submitted by Brad Tombaugh on 2 March 2010 - 8:48am

Tonight, 2 March 2010, is the premier of "The Pluto Files" on the PBS science series "Nova." Pluto was discovered on February 18, 1930 by Clyde W. Tombaugh, the first planet discovery by an American. In 2006, its status was changed to dwarf planet amid much controversy. This episode of Nova explores the history of Pluto and the decision and reactions to its change in status. If you miss tonight's broadcast, the episode will be available on-line starting tomorrow, 3 March 2010.

Y2K10 Bug

Submitted by Brad Tombaugh on 6 January 2010 - 4:33pm

Since the beginning of the year, I've noticed that I had started to catch good email in my Mac OS X Server's email spam filter. It was odd, since it generally works quite well, and rarely catches any "false positives." This morning at my office, one of the guys I work with was having to patch one of our systems because of a "Y2K10 bug" where the date isn't interpreted correctly.

In Memory of Charles Junior Gaede 1920 - 2009

Submitted by Brad Tombaugh on 25 February 2009 - 8:00pm

My father-in-law, Charles Junior Gaede, passed away on 24 February 2009 at age 89. He
was born in Richmond, Indiana on 11 February 1920 to Ruth Vera (Gehring) and Charles
Louis Gaede.

In 1936 he quit high school and performed odd jobs. He also painted houses for his
father for $35 per week. From 1939 to 1941 he worked in a camera shop in Richmond,
Indiana. This was an important position for Charles, as it became his goal to own his
own camera shop.

Welcome Baby Zoe!

Submitted by Brad Tombaugh on 1 July 2008 - 10:46am

Welcome Baby Zoe! Congratulations to my sister, Meagan, and brother-in-law Mike. Zoe was born on July 1st at 9:46 am, weighing in at 8 pounds even, and 20 inches long. It sounds like Zoe, Mom and Dad, and big sister Savannah are all doing well. There is more at Meagan's blog.

Updates and Desktop Pictures

Submitted by Brad Tombaugh on 23 January 2008 - 8:00pm

I've come to the conclusion that spammers have used a web crawler to harvest email addresses from my website, so I've removed all of the email links, including the pages for Friends and Family. I will clean up those pages and link them back in as soon as I have time.