April 14th, 2008

http://mrtmag.com/mag/radio_mhz_challenges_far/

ftp://download.intel.com/technology/wimax/10367.pdf

http://www.altera.com/literature/an/an434.pdf

http://www.digit-life.com/articles2/mobile/wimax.html

http://www.cs.tut.fi/kurssit/TLT-6556/Slides/3-802.20.pdf

http://www.picochip.com/solutions/wimax

http://www.dailywireless.org/2005/05/05/sprint-intel-mobile-wimax/

http://smartmobilegadgets.wordpress.com/2007/07/31/wimax-wireless-broadband/

http://www.3gamericas.org/English/Technology_Center/QA/ofdmqa.cfm

Posted in comm | No Comments »
April 9th, 2008

http://www.dvb-h.org/ 
http://www.mediaflo.com/

If outside readers of this blog cannot tell by now, I am a fan of the visual (more than the audio). This is probably because I am half deaf and rely on my seeing more than my hearing. (WOW something about me! We haven’t heard about me in a very long time.)

Anyway, one of the interesting and emerging technologies is handheld video broadcasting. Current video media distribution in domestic (US) mobile/cellular networks is a one-to-one connection. A good example is Verizon’s V-Cast. The way it works is a user subscribes to this service. He or she is given a list of media then he or she requests to download that media to his or her handheld. It’s a communication between the giver (the server) and the receiver (the user). An analogy would be a landline phone conversation between two people. The conversation is exclusively between two people.

The emerging technologies, MediaFLO (US) and DVB-H (Euro), take the idea of a television broadcast, scaled it in such a way so that a phone can process it. This is a BROADCAST. Hopefully you know what that means. This is a one-to-many connection which is similar to being in a lecture hall, or tuning into a radio station. In the simple case, the lecture hall, the speaker discusses a topic and projects it out to his/her audience. The audience doesn’t have much influence on the material being lectured; he or she can only choose to listen or not. The action of listening or not is tuning in or out. Radio is the most tangible example of tuning in or out; if we were to use the lecture hall analogy, it would be lecture hall hopping.

 A one-to-many connection is desired in a mobile communications network since you are giving content a-la-carte. Because there are so many users in your network, it seems illogical to repetitively supply content on a per-demand basis. A case when you would want a one-to-one connection for video would be to have an actual video conference; similar to a private conversation.

Posted in comm | No Comments »
April 7th, 2008

Radiotelephon (push to talk)
http://en.wikipedia.org/wiki/Radiotelephone

Emergency Broadcast System (old)
http://en.wikipedia.org/wiki/Emergency_Broadcast_System

Emergency Alert System (new)
http://en.wikipedia.org/wiki/Emergency_Alert_System

Posted in comm | No Comments »
April 7th, 2008

Wimax
http://www.wimax-industry.com/eq/wimaxbasestationequipment.htm

questions about cell phones
http://www.hps.org/publicinformation/ate/faqs/cellphoneqa.html

wiki on base station subsystems
http://en.wikipedia.org/wiki/Base_Station_Subsystem

unstrung: a website on wireless (specifically for base station transcievers) http://www.unstrung.com/topics.asp?node_id=312

DVB-H:
http://www.cio-today.com/story.xhtml?story_id=012000PM271O

Posted in comm | No Comments »