Patent EA-002245-B1 (EA)
Title: Seamless lobe handover
Inventor: ANDERSSON HENRIK
IPC: H04B7/04
Filed: 1998-10-20
Abstract: 1. A method in a telecommunication system for communication between at least one base station site having one or more sectors each divided into a number of fixed lobes and a mobile station moving within said base station site, comprising: - establishing a connection forming a channel between a base station site transmitter/receiver equipment and a mobile station; - transmitting signals between said transmitter/receiver equipment and said mobile station via said channel by utilizing one of said lobes in one of the sectors of said base station; - changing said utilized lobe to another lobe of said base station site without changing transmitter/receiver equipment of said base station site, thus being devised to achieve seamless lobe handover within the base station site, utilizing at a time only one lobe and without changing the channel. 2. A method as claimed in claim 1, characterized in that an antenna array and its supporting equipment is used to form fixed lobes. 3. A method as claimed in claim 1 or 2, characterized in that the change of the lobe is made without any signalling or channel order to and from said base station site to control the change of the lobe. 4. A method as claimed in any of the preceding claims, characterized in that equipment in said base station site determines the best lobe by comparing signals received in actual lobe with signals received in adjacent lobes. 5. A method as claimed in claim 4, characterized in that signals are compared by detecting received signal strength. 6. A method as claimed in claim 4, characterized in that signals are compared by evaluating received signal to interference ratio. 7. A method in a telecommunication system for communication between at least one base station site having a plurality of sectors each divided into a number of fixed lobes and a mobile station moving within said base station site, comprising: - establishing a connection forming a channel between a base station site transmitter/receiver equipment and a mobile station; - transmitting signals between said transmitter/receiver equipment and said mobile station via said channel by utilizing one of said sectors of said base station; - changing said utilized sector to another sector without changing transmitter/receiver equipment of said base station site, thus being devised to achieve seamless lobe handover within the base station site, utilizing at a time only one sector and without changing the channel. 8. A method as claimed in claim 7, characterized in that the change of the sector is made without any signalling or channel order to and from said base station site to control the change of the sector. 9. A method as claimed in claim 7 or 8, characterized in that equipment in said base station site determines the best lsector by comparing signals received in actual sector with signals received in adjacent sectors. 10. A method as claimed in claim 9, characterized in that signals are compared by detecting received signal strength. 11. A method as claimed in claim 9, characterized in that signals are compared by evaluating received signal to interference ratio. 12. A base station site in a telecommunication system, said base station site comprising a transmitter/receiver equipment connected to an antenna for establishing contact and communicating with a mobile station on a channel within the coverage are of said base station site, said coverage area being divided into sectors, each sector being divided into a number of fixed lobes, characterized in that a lobe selecting unit, intermediate said transmitter/receiver equipment and said antenna, devised to select one lobe at a time defined by said antenna for communication between said transmitter/receiver equipment and a mobile station, and capable of changing the connection from said transmitter/receiver equipment to another lobe without changing the channel, thus being devised to achieve seamless lobe handover within the base station site. 13. The base station site as claimed in claim 12, wherein said antenna related equipment comprises a fixed lobe antenna array, and said lobe selecting unit comprises an antenna array related equipment, devised to select one amongst a plurality of fixed lobes defined by said antenna array. 14. The base station site as claimed in claim 12, wherein said lobe selecting unit comprises an antenna selection equipment, connectable to one amongst a plurality of antennas, each antenna defining one fixed sector. 15. The base station site as claimed in claim 14, wherein each of said antennas comprises an antenna array related equipment, devised to select one amongst a plurality of fixed lobes defined by respective antenna arrays, within said sector.