摘要 |
Microcells, located within an umbrella cell, are provided with a listen-only control channel at the same frequency as the uplink control channel of the umbrella cell. During call access the umbrella cell and microcells determine signal strength, forwarding information to the system. The most appropriate cell to handle the call is selected, causing the umbrella cell to respond on its down link control channel. This produces several uplink and one down link control channel. |