What is GSM Handover ?
GSM Handover
The user movements can produce the need to change the channel or cell, specially when the quality of the communication is decreasing. This procedure of changing the resources is called handover. Four different types of handovers can be distinguished:
- Handover of channels in the same cell.
- Handover of cells controlled by the same BSC.
- Handover of cells belonging to the same MSC but controlled by different BSCs.
- Handover of cells controlled by different MSCs.
Handovers are mainly controlled by the MSC. However in order to avoid unnecessary signalling information, the first two types of handovers are managed by the concerned BSC (in this case, the MSC is only notified of the handover).
The mobile station is the active participant in this procedure. In order to perform the handover, the mobile station controls continuously its own signal strengh and the signal strengh of the neighboring cells. The list of cells that must be monitored by the mobile station is given by the base station. The power measurements allow to decide which is the best cell in order to maintain the quality of the communication link. Two basic algorithms are used for the handover:
1.The `minimum acceptable performance’ algorithm. When the quality of the transmission decreases (i.e the signal is deteriorated), the power level of the mbbile is increased. This is done until the increase of the power level has no effect on the quality of the signal. When this happens, a handover is performed.
2. The `power budget’ algorithm. This algorithm performs a handover, instead of continuously increasing the power level, in order to obtain a good communicatio.
One Response to “Mobile Terminated Call”
By Free WP Themes on Sep 23, 2010 | Reply
Nice post and this enter helped me alot in my college assignement. Say thank you you seeking your information.