What is Tetra?
The government recently sold off the existing emergency services radio frequencies to the mobile telephone companies for £20 billion.
To replace these outdated and inefficient systems, the government purchased Tetra for £3 billion. Tetra stands for Terrestrial Trunk Radio Access.
It is a microwave radio communications system which will require some 3000 base station masts to support the many mobile units.
Unlike mobile phone masts which are only in action when users call on them, Tetra is 'on' round-the-clock 24 hours a day.
mmo2 operated by Airwave (the BT off-shoot responsible for rolling out the system in the UK) plan to cover the whole country. Tetra has only been in use for 2 years starting in Lancs but already there are many concerns and health issues amongst the users and those living near to the masts.