Frequency Assignment – Models and Algorithms

Wireless connections are established by the use of a transmitter which is sending radio waves at a specific frequencies to a receiver. Nowadays, due to the variety of different services, only a restricted part of the radio spectrum is available. The set of available frequencies for a provider of a wireless communication service is limited even further by concurrent providers and local frequency blockings. To overcome this shortage, frequencies are used simultaneously by many connections. However, if multiple signals are transmitted at the same or close by frequencies, these signals may interfer the dedicated signal a receiver is listening to, resulting in a loss of quality at the recieving end of the connection. Therefore, the allocation of frequencies to wireless connections is a task that has to be carried out very carefully, in order to avoid, or second best, to minimize interference in the network. This task is known as “frequency assignment” or “channel assignment”.