| 摘要 |
Within a telecommunication cell there are two frequency bands available for use, 900 MHz and 1800 MHz, of which a mobile user is assigned to. If it appears that the quality of the other frequency is better, then the system can hand over the mobile user to the other frequency, known as intra cell hand over. However, if the quality is not actually better, this can result in a user being passed back and fore between the frequencies repeatedly when it would be more beneficial to remain on a single frequency (known as ping pong handover). This reduces power efficiency and increases system resources. This is overcome by counting the number of handovers within a certain time. If this number exceeds a predetermined threshold, then no handovers are allowed to take place for a second predetermined period of time. |
