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How wireless phone networks are using RF

How wireless phone networks are using RF

The wireless bands that are used for commercial use are divided into two categories. One is regulated and the other isn’t. The regulated RF-bands are used for cellular phones, broadcasting television and radio programs. There are also some ranges that are not for commercial use like those for military use or satellite communications. On the other hand there are unregulated frequencies that the public can use. You don’t need a license to use those and it is shared among the public.

Shielding off RF radiation

You can imagine that, over the years, the increasing use of the ether has caused more and more interference. Signals clash and cause wireless devices to malfunction. Being able to shield off certain frequencies has become more important these days. Especially when testing sensitive devices it’s important to keep signals clean. Innovative solutions are there to improve shielding against RF noise and interference. DMAS provides a whole range of such solutions to be able to get clean signals in a testing environment. Solutions are offered for RF waves, but also microwaves. The innovative walkway absorbers are even able to block out electromagnetic waves coming from the floor. This way a whole room can be isolated from electromagnetic interference.

Cellular networks based on RF

Besides being able to test radio waves it should also be put in use with all the noise in the air. So how does a wireless phone network actually work? These networks are also called cellular networks. The reason for this is that all the areas are divided into cells. Within each cell certain frequencies are divided amongst radio base stations. These base stations are essential for wireless phone communications. For example when a wireless phone makes a call it cannot communicate directly with the device you are trying to reach. This is because the Earth is round and signals are ejected into space, because they do not bend around the surface of the planet, but go in a straight line. Also the signal will weaken over a distance due to dampening effects of the medium through which the signal passes. So from time to time the electromagnetic wave needs to be picked up and broadcasted again under a different angle to curve around the Earth and to reinforce the signal. The base station is responsible for picking up the radio waves with their antennas and amplifying the signal to the next station or the phone that is being called. Certain bands of radio frequencies can, in this way, be reused over and over again as long as base stations next to each other don’t use the same frequency. Because all these cells have their own unique set of frequencies it’s possible for multiple users to make use of their local cell without it being flooded by too many requests. All the calls, which take place in many different places, are therefore divided between all the different cells in an area which reduces the load on a single frequency. This makes it possible to increase the capacity of the whole network.