METHOD AND APPARATUS FOR SHORT HANDOVER LATENCY IN WIRELESS COMMUNICATION SYSTEM USING BEAM FORMING
First Claim
1. A method for handover in a Mobile Station (MS) of a wireless communication system which adjusts a beam direction, the method comprising:
- sending a scan request message for scanning a downlink (DL) beam or a DL beam and uplink (UL) beam with respect to a serving base station (BS) and a neighboring BS, to the serving BS;
receiving a scan response message;
determining the DL beam or the DL beam and UL beam for the MS by performing scanning or the scanning and association with the serving BS and the neighboring BS based on the scan response message;
sending a scan report message comprising a result of the scanning or the scanning and the association to the serving BS;
when receiving an air handover (HO) request message from the serving BS, generating an air-HO response message comprising information of a neighboring handover BS to which the MS hands over based on the air-HO request message;
performing beam selection with the neighboring handover BS based on the air-HO request message; and
performing handover, and transmitting and receiving data to and from the neighboring handover BS.
1 Assignment
0 Petitions
Accused Products
Abstract
Beam selection is provided. A method for handover in a mobile station includes sending a scan request message for scanning a downlink (DL) beam with respect to a serving base station (BS) and a neighboring BS, to the serving BS, and receiving a scan response message; determining the DL beam for the MS by performing scanning with the serving BS and the neighboring BS based on the scan response message; sending a scan report message comprising a result of the scanning to the serving BS; when receiving an air-HO request message from the serving BS, generating an air-HO response message comprising information of a neighboring BS to which the MS hands over based on the air-HO request message; performing beam selection with the neighboring BS of the handover based on the air-HO request message; and performing the handover.
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Citations
47 Claims
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1. A method for handover in a Mobile Station (MS) of a wireless communication system which adjusts a beam direction, the method comprising:
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sending a scan request message for scanning a downlink (DL) beam or a DL beam and uplink (UL) beam with respect to a serving base station (BS) and a neighboring BS, to the serving BS; receiving a scan response message; determining the DL beam or the DL beam and UL beam for the MS by performing scanning or the scanning and association with the serving BS and the neighboring BS based on the scan response message; sending a scan report message comprising a result of the scanning or the scanning and the association to the serving BS; when receiving an air handover (HO) request message from the serving BS, generating an air-HO response message comprising information of a neighboring handover BS to which the MS hands over based on the air-HO request message; performing beam selection with the neighboring handover BS based on the air-HO request message; and performing handover, and transmitting and receiving data to and from the neighboring handover BS. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A method for handover in a serving Base Station (BS) of a wireless communication system which adjusts a beam direction, the method comprising:
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receiving a Scan_Request message for scanning a downlink (DL) beam or a DL beam and uplink (UL) beam for a mobile station (MS), from the MS, receiving a dedicated ranging code of the MS from a neighboring BS through negotiation with the neighboring BS; sending a scan response message comprising information about whether to perform scanning or the scanning and association, to the MS; receiving from the MS a scan report message comprising information of the DL beam or the DL beam and UL beam for the MS and a result of the scanning or the scanning and the association; sending a network handover (NW-HO) request message to at least one neighboring BS based on the scan response message in order to identify a BS capable of supporting handover of the MS and to share context of the MS; receiving a NW-HO response message comprising information indicating whether the handover of the MS is supportable, from the at least one neighboring BS; sending an air-HO request message to the MS based on the NW-HO response message, and receiving an air-HO response message comprising information indicating whether the MS is able to hand over and information of at least one neighboring BS to which the MS hands over; and sending a NW-HO confirm message informing whether the handover of the MS is performed, to the neighboring BS which sends the NW-HO request message based on the air-HO response message. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16)
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17. A method for handover in a neighboring base station (BS) of a wireless communication system which adjusts a beam direction, the method comprising:
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sending a dedicated ranging code of a mobile station (MS) to a serving BS through negotiation with the serving BS; performing association with the MS to scan a downlink (DL) beam or DL beam and uplink (UL) beam for the MS; receiving from the serving BS a network handover (NW-HO) request message based on a scan response message comprising a result of scanning or the scanning and association of the MS in order to identify a BS capable of supporting handover of the MS and to share context of the MS; generating and sending a NW-HO response message comprising information indicating whether the handover of the MS is supportable, to the serving BS; receiving from the serving BS a NW-HO confirm message informing whether the handover of the MS is performed, to the neighboring BS which sends the NW-HO request message based on the air-HO response message; performing beam selection with the MS based on the NW-HO confirm message; and transmitting and receiving data to and from the MS which hands over. - View Dependent Claims (18, 19, 20, 21, 22)
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23. An apparatus of a mobile station (MS) for handover in a wireless communication system which adjusts a beam direction, the apparatus comprising:
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a receiver configured to receive at least one reference signal from a base station (BS) in at least one downlink (DL) Tx beam direction; a transmitter configured to send a ranging signal to the BS in at least one uplink (UL) Tx beam direction; a channel estimator configured to estimate a channel according to the at least one DL Tx beam direction using the at least one reference signal; and a controller configured to select DL and UL beams between the BS and the MS by considering channel information according to the at least one DL Tx beam direction, and control to send and receive messages to and from the BS. - View Dependent Claims (24, 25, 26, 27, 28, 29, 30)
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31. An apparatus of a serving base station (BS) for handover in a wireless communication system which adjusts a beam direction, the apparatus comprising:
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at least one antenna comprising a plurality of antenna elements; a transmitter configured to send at least one reference signal in at least one downlink (DL) Tx beam direction; a receiver configured to receive channel information according to at least one uplink (UL) Tx beam direction from a mobile station (MS); a controller configured to select the UL Tx beam direction by considering the channel information according to at least one uplink (UL) Tx beam direction received from the MS through the receiver, select DL beam and UL beam between the MS and the serving BS by sending and receiving messages for the MS in consideration of the selected UL Tx beam direction, and provide information for handover to the MS; and a plurality of Radio Frequency (RF) paths connected to the respective antenna elements, and configured to form a beam to send a signal to the MS according to the DL Tx beam direction selected by the controller. - View Dependent Claims (32, 33, 34, 35, 36, 37, 38, 39, 40)
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41. An apparatus of a neighboring base station (BS) for handover in a wireless communication system which adjusts a beam direction, the apparatus comprising:
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at least one antenna comprising a plurality of antenna elements; a transmitter configured to send at least one reference signal in at least one downlink (DL) Tx beam direction; a receiver configured to receive channel information according to at least one uplink (UL) Tx beam direction from a mobile station (MS); a controller configured to select the UL Tx beam direction by considering the channel information according to at least one UL Tx beam direction received from the MS through the receiver, select DL beam and UL beam between the MS and the serving BS by sending and receiving messages for the MS in consideration of the selected UL Tx beam direction, and provide information for handover to the serving BS; and a plurality of Radio Frequency (RF) paths connected to the respective antenna elements, and configured to form a beam to send a signal to the MS according to the DL Tx beam direction selected by the controller. - View Dependent Claims (42, 43, 44, 45, 46, 47)
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Specification