Detecting WiFi, a kilometer away, with an Android?

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This memorial day weekend, I went camping out of a bed and breakfast that had open wifi. When I went out on a hike one afternoon, I decided to see what kinds of wifi signals I could get I could get on my Android phone. I got on top of a pretty tall peak where I could see the bed and breakfast.
Ground level view of the wifi source.
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I was surprised when I was still detecting the wifi signal from the bead and breakfast (although it was very faint).
WiFi Analyzer screen shot of wifi
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When I got back home and saw how far away I really was, I found that I was about a kilometer away.
Sky view of wifi source
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I could only establish a very sketch connection that would only last a few seconds, barely enough to load a single web page before cutting out. I think it's really phenomenal that consumer grade wifi devices can get range like this. Granted the source and I were in direct line of site to each other and I was in a rural area with minimal interference.

Has anyone else seen anything similar to this?
Try using parabolic chineese cook wear (a WOK or a WOK lid) to boost the signal. I often get 20+ dB of gain from a $1 thrift store special. I have used it to still transfer data at 5 mbps at 1 km from my house. I did not go further because I lost line of sight. Just put the antenna close to the focal point. I determined that by focusing the sun on my hand, till it got how. Just a plain metal (conducting) sheet will often give you 3 DB.

Search google there are tons of examples.

With line of sight all you need is power or antenna gain. The last I knew the unofficial wifi link record was 140km. Done using 2 4m dishes between two mountain tops in Poland. There was a DefCon contest going for a while that made 70km in Nevada.

You don't need to use a solid wok either. A spider(dumpling) wok may be more parabolic than a standard wok and behaves like a solid sheet at 2.4ghz. My personal best is with a 200mw card that will sustain a 1/4 mile link at 5.5mbit. I used a cd as a reflector for a 4k link @ w mbit. Also you can transmit farther over a weak link if you can force your device to a slower speed.

Lastly you may want to look into getting an amateur radio license in your country. Most of the huge distance records seem to have call letters attached to the participants names.
  • Have you driven today?

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