RADIO RESOURCE MANAGEMENT

It is the level control of interference and the other characteristics in wireless communication systems , e.g cellular networks, wireless and broadcasting systems. It involves algorithms for controlling parameters such as transmit power, user allocation , data rates, handover criteria and error coding scheme etc. it concerns multi-user and multi cell network capacity issues rather than point to point channel capacity.  In traditional telecommunications research and education it uses channel coding and source coding with a single user in mind although it may not be possible to achieve the maximum channel capacity when several users and adjacent base stations share the same frequency channel.  RRM is especially important in systems limited by co-channel interference rather than by noise, for example cellular systems and broadcast networks homogeneously covering large areas, and wireless networks consisting of many adjacent access points that may reuse the same channel frequencies.

The cost for deploying a wireless network is normally dominated by base station sites (real estate costs, planning, maintenance, distribution network, energy, etc.) and sometimes also by frequency license fees. The objective of radio resource management is therefore typically to maximize the system spectral efficiency in bits/sec, that the grade of service should be above a certain level. The latter involves covering a certain area and avoiding outage due to co-channel interference, noise, attenuation caused by path losses, fading caused by shadowing and multipath, Doppler shift and other forms of distortion. The grade of service is also affected by blocking due to admission control or inability to guarantee quality of service that is requested by the users.

Static RRM involves manual as well as computer-aided fixed cell planning or radio network planning. E.g:

1.     Frequency allocation band plan

2.     Antenna heights

3.     Antenna directions

4.     Modulation and coding parameters

5.     Antenna space diversity.

Dynamic RRM schemes adjust the radio parameters to tha traffic load, user mobility, quality of service requirements etc.e.g:

1.     Power contraol algorithms

2.     Link adaption algorithms

3.     Dynamic channel allocation.

 

INTER-CELL RRM:

Networks like LTE standard are designed for a frequency reuse of one. Thus neighbouring cells use the same frequency spectrum.such standards exploits Space Division Multile Access and can be highly efficient but requires close coordination between cells to avoid intercell interference. Intercell RRM coordinates resourse allocation between different cell sites by using MIMO techniques.