Today we take our mobiles for granted. You dial a number and directly your call will end up at the right place. Many of us probably don’t think about our mobile calls more than that. But much of what we take for granted today posed big problems in the past.
Mobile phones mounted in cars have been around for a long time, ever since 1956. These had fully automatic calls and thus did not require any physical operator to direct the call properly. But there was a geographical restriction on these phones because they were tied to a so-called base station, a specific mast to which that particular phone belonged. If the mobile phone was too far from the station, it you could not make a call.
When mobile phones really started to break through, there was no uniform standard for how wireless communication should take place. Especially not when it comes to long distance calls. That’s when NMT was created, what we today call the first generation of mobile telephony. This was created in response to the congestion and heavy demands of the manual cellular networks.
With NMT, anyone could call anyone, anywhere with your mobile phone. You no longer needed to know where the cell phone you were trying to call was located. A separate number series was required as well as a computerized system that kept track of where the phones were located, i.e. roaming.
NMT stands for Nordic Mobile Telephone and is an analog mobile telephone network that was jointly built up in the Nordic countries. NMT was a fully automated network created for the public and put into operation after ten years of development.
Although NMT was a Nordic invention, the Nordic countries were not first out with the NMT system. It was in Saudi Arabia that the system was first launched in 1981. Only a few months later, the system also began to be used in Sweden and Norway. The following year Finland and Denmark started and Iceland joined a few years later. By 1985, the network in the Nordic region had grown to 110,000 users, making it the largest mobile network at that time. Many European and Asian countries then adopted the same system.
The specifications for NMT were free and open. This enabled many companies to create NMT hardware, which in turn lowered prices.
So what was so great about NMT? Well, NMT had a superior range compared to other systems. Even if you were far away from a mast, you could still place a call. This was particularly favorable in countries with a sparse population, such as Iceland or northern Sweden. Since later systems often reach a large percentage of the population of the country, there are still large land areas that have no coverage at all. NTM, on the other hand, reaches almost the entire land surface and also a good distance out to sea.
The longer reach in the system was due to two different things. Partly, NMT had a lower frequency, which allowed the signals to travel longer. With the lower frequency, the wavelength became longer and so you could be farther from the mast. In addition, NMT phones had a higher transmission power. An NMT 450 phone is allowed to have a transmit power of 15 watts while a GSM phone (second generation telephony, 2G) has a maximum of 6 watts only.
NMT was decommissioned on December 31, 2007, after the shutdown had been postponed for about two years. It was the company Nordic Mobile Phone, now called Net1, which expanded a digital mobile network within the same frequency range. In this way, they gained access to the frequency channels that NMT used, giving Net1 access to the entire frequency space of the 450 MHz band. This means that Net1 has a very good coverage throughout Sweden. According to Net1, you can be up to 74 miles off the coast and still get mobile broadband because of the frequency.
It is easy to forget the many years that have been required to develop the mobile services we use today. And who knows, in 10 years, users may think that the way we use mobiles today is outdated and obsolete.