Mobile Telephone Service

The Mobile Telephone Service (MTS) is a pre-cellular VHF radio system that links to the Public Switched Telephone Network (PSTN). MTS was the radiotelephone equivalent of land dial phone service. As of 2012, only rural and wilderness areas were still using the system. The Mobile Telephone Service was one of the earliest mobile telephone standards. It was operator assisted in both directions, meaning that if one was called from a land line the call would be routed to a mobile operator, who would route it to one's phone. Similarly, to make an outbound call one had to go through the mobile operator, who would ask for the mobile number and the number to be called, and would then place the call. This service originated with the Bell System, and was first used in St. Louis on June 17, 1946. The original equipment weighed 80 pounds (36 kg), and there were initially only 3 channels for all the users in the metropolitan area, later more licenses were added bringing the total to 32 channels across 3 bands (See IMTS frequencies). This service was used at least into the 1980s in large portions of North America. [1] On October 2, 1946, Motorola communications equipment carried the first calls on Illinois Bell Telephone Company's new car radiotelephone service in Chicago.[2][3] Due to the small number of radio frequencies available, the service quickly reached capacity. MTS was replaced by Improved Mobile Telephone Service (IMTS). These channels are prone to network congestion and interference since a radio closer to the terminal will sometimes take over the channel due to having a more powerful signal. The service uses technology that has been manufacturer discontinued for more than three decades. The driver for replacement in most of North America, particularly large cities, was congestion, the inability of the network to carry more than two dozen channels in a geographic area. Cellular service resolved this congestion problem very effectively, especial y since cellular frequencies, typically UHF, do not reach as far as VHF frequencies and can therefore be reused. The ability of a cellular system to use signal strength to choose channels and split cells into smaller units also helps expand channel capacity. The driver for replacement in remote areas, however, is not network congestion, but obsolescence. Because the equipment is no longer manufactured, companies still using the service must struggle to keep their equipment operating, either by cannibalising from retired equipment or improvising solutions. Due to insufficient traffic, cellular is not a cost-effective replacement. Currently, the only viable solution is satellite telephony, as the small number of "base stations" orbit the planet serving large geographic regions as they pass over. Cost, however, has been an issue, and the replacement will become acceptable to VHF mobile customers gradually, as the cost of satellite telephony has been dropping and will continue to drop. Many MTS frequencies are now used for local paging services. They are only found in some parts of rural North America, having been replaced in most areas by cellular service in the 1980s or later. The service territory of Northwestel has only eliminated ten MTS locations since 2003; in the case of six sites, cellular is available and the company had to rent tower space for five sites, making them even more unprofitable; four other sites had near zero traffic. The remainder of the MTS network is still operating, though at a deficit, virtually blanketing the Yukon and northern British Columbia highway network, the western Great Slave Lake region, the Mackenzie River and the Mackenzie Delta. As noted above, cellular service is too costly to install in these areas due to a more limited signal reach, cellular sites are more complex technology, and they would still require the same logistical support, like electricity supplied from diesel generators, using barged-in fuel.