Rayleigh Fading in GNU Radio | Carriers Everywhere

https://www.bastibl.net/rayleigh-autocorrelation/

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O’Shea Research | Radio and Machine Learning Zen

https://oshearesearch.com/

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Good article on UDP vs TCP

I am currently working on a project that involves satellite based radios and digital data exchange. During a test of the project the system started having all sorts of problems that the main contractor and customer could not figure out. I was asked to take trouble shoot the problem over the phone. I asked the main contractor, who built all the networking system that is transparent to our project, and asked what protocol they were using for transport. They stated UDP. So I immediately asked what Quality of Service had been implemented. They asked what I meant which got me worried. So I asked how they were handling packet delivery (priority, order, etc), how they were dealing with data loss, data delays, data corruption, acknowledgements, etc. They told me they were not doing any of that but it was not needed because they had been testing the system for two years and never had an issue. Asking how they had tested the system I found out they had only tested the system over WiFi and 4G with small numbers of units and using an application that was not sensitive to data loss. Long story short we were able to confirm that the problem was lack of QoS being implemented into UDP by monitoring the data traffic at the wire where you could see packets getting dropped, lost, having huge round trip delays, etc. This resulted in me having to try to explain to the engineer that while it makes sense to use UDP for stacoms instead of TCP/IP you still have to implement various mechanisms that you find in TCP/IP on UDP in many cases. This was surprisingly hard discussion which led me to look for a nice explanation which I found with this article called UDP vs. TCP by Glenn Fiedler. This article is part of a series of articles he wrote around networking for games and while its game centric many of the items he discusses will arise whenever you need to use UDP. Whether you use UDP to try to speed up data transfer or because you’re working with extremely bandwidth limited applications that same set of patterns appear. As such I highly recommend check out these articles which are written at a level that a layman or an experience developer will understand easily.

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Decent tips for reducing data usage by apps on your Android device

Many people don’t realize that most apps, regardless of OS, make all sorts of network calls. Sometimes this is to check for things like updates or important notifications but usually its because your applications are sending data home with information on your app usage and other such things. This can eat away at your plans data limits. To help control this you can use the following tip to control those appa pesky data calls on your cellular service.
http://www.ghacks.net/2015/04/09/restrict-app-data-on-cellular-networks-on-android/

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Useful tool for uninstalling all the bloatware on your windows computer

Bulk Crap Uninstaller removes multiple programs silently on Windows http://www.ghacks.net/2015/04/10/bulk-crap-uninstaller-removes-multiple-programs-silently-on-windows/

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Great explanation of Bayes Theorem

When I first learned Bayes Theorem from a text book for some reason I had a hard time with it. What ended up making it stick for me was sitting down and writing several little programs implementing Bayes. I like this article though http://www.countbayesie.com/blog/2015/2/18/bayes-theorem-with-lego were they use legos to help you visualize how bays works. Very neat and fun.

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Fear of Drones

Wired has a interesting article governments fear of commercial an DIY drones here. One of the things they point out is how one company is forcing a mandatory firmware on its drones to create a no go geofence. This is a bit silly since most drones are pretty easy to hack, the ones that are not tend to get ignored, as well as the ones that are hard to hack will still get hacked by enthusiasts if they really want the product. That and bad guys are of course going to hack hardware if it has capabilities they want. That being said stopping COTs drones is really not that hard. Its odd that people are getting so frantic about it.

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