System and method of supporting softer handover in a cell using adaptive antenna in enabling narrow beam operation

A radio base station in a cellular radio communication system, said-radio base station being operable for serving at least one mobile unit and having adaptive antennas for enabling narrow beam operation, wherein said radio base station comprises:

• a processing circuitry configured to receive a radio link setup request from a network control unit for configuration of a new serving radio link in a neighboring cell for a selected mobile unit, wherein the network control unit has determined that the new serving radio link is needed based on downlink quality measurements;
• the processing circuitry further configured to perform, upon receiving said radio link setup request and before responding to said radio link setup request, uplink measurements with respect to said mobile unit and for selecting, based on said uplink measurements, a narrow target beam within the neighboring cell served by said radio base station;
• the processing circuitry further configured to configure said new serving radio link for said mobile unit directly with the selected narrow target beam while said radio link setup request is pending, wherein said radio link setup request is incomplete with respect to the setup of said new serving radio link, and information of the selected narrow target beam constitutes complementary information for setup of said new radio link directly with the selected narrow target beam;
• and
• the processing circuitry further configured to send information representative of the selected narrow target beam to said network control unit in a radio link setup response.

A network control unit for supporting handover between cells in a cellular radio communication system, said cellular radio communication system having adaptive antennas for enabling narrow beam operation, wherein a mobile unit is served by an active cell set of at least one cell in said cellular radio communication system, wherein said network control unit comprises:

• a processing circuitry configured to send a radio link setup request from the network control unit to a selected radio base station for configuration of a new serving radio link in a neighboring cell for said mobile unit, wherein the network control unit has determined that the new serving radio link is needed based on downlink quality measurements;
• the processing circuitry further configured to receive, in a radio link setup response from said radio base station, information representative of a narrow target beam selected for said new radio link by said radio base station based on uplink measurements with respect to said mobile unit;
• wherein said radio link setup request is incomplete with respect to the setup of said new serving radio link, and information of the selected narrow target beam constitutes complementary information for setup of said new radio link directly with the selected narrow target beam while said radio link setup request is pending with said selected radio base station;
• and
• the processing circuitry further configured to inform said mobile unit that said new serving radio link is associated with said radio base station and said selected narrow target beam.