Posts: 1
Threads: 1
Joined: Feb 2010
18-02-2010, 08:35 AM
iam found no information about my seminar topic "TERRESTRIAL TRUNKED RADIO".
Friends plssssssssssssssss help me out.
Only two days for me.
Posts: 1,061
Threads: 613
Joined: Feb 2010
read this
TETRA (Terrestrial Trunked Radio) is a set of standards developed by the European Telecommunications Standardisation Institute (ETSI) for two-way transceiver (colloquially known as a walkie talkie) specification. TETRA was specifically designed for use by government agencies, emergency services, (police forces, fire departments, ambulance), rail transportation staff, transport services and the military. that describes a common mobile radio communications infrastructure throughout Europe. This infrastructure is targeted primarily at the mobile radio needs of public safety groups (such as police and fire departments), utility companies, and other enterprises that provide voice and data communications services.All of these groups have been high-end users of private/professional mobile radio (PMR) or public access mobile radio (PAMR) technology. This is especially true in the areas of law enforcement and public safety, where fast and accurate field communications to and from a central office or dispatcher are often critical. TETRA is a standard solution for groups that use both PMR and PAMR., when European disasters have struck, emergency response teams from several European nations had a difficult time communicating with each other, due in part to the lack of standardization in their mobile radio equipment. The TETRA standards evolved to answer this communication challenge as well as others faced or anticipated by the European Commission (EC) in its efforts to unify European countries. TETRA uses Time Division Multiple Access (TDMA) with four user channels on one radio carrier and 25 kHz spacing between carriers. Both point-to-point and point-to-multipoint transfer can be used. Digital data transmission is also included in the standard though at a low data rate.TETRA Mobile Stations (MS) can communicate Direct Mode or using Trunked infrastructure (Switching and Management Infrastructure or SwMI) made of TETRA Base Stations (TBS). As well as allowing direct communications in situations where network coverage is not available, Direct Mode or DMO also includes the possibility of using one (or a chain) of TETRA terminals as relays for a signal. This functionality is called DMO gateway (from DMO to TMO) or DMO Repeater (DMO to DMO). In Emergency situations this feature allows direct communications underground or in areas of bad coverage.
more on
http://en.wikipediawiki/Terrestrial_Trunked_Radio
http://simt.si/pdf/Uvod_TETRA.pdf
http://ascomen/tetra-article.pdf
http://spinrootspin/Workshops/ws99b/ug090060.pdf
Posts: 7,939
Threads: 421
Joined: Jun 2012