US Patent No. 10,560,891

MEDIUM ACCESS CONTROL IN LTE-U


Patent No. 10,560,891
Issue Date February 11, 2020
Title Medium Access Control In Lte-u
Inventorship Eswar Vutukuri, Hampshire (GB)
Takashi Suzuki, Tokyo (JP)
Nicholas William Anderson, Warmley (GB)
Zhijun Cai, Herndon, VA (US)
Assignee BlackBerry Limited, Waterloo, Ontario (CA)

Claim of US Patent No. 10,560,891

9. A user equipment (UE), comprising:a memory; and
one or more processors communicatively coupled with the memory and configured to:
receive, from an eNB and on a long term evolution (LTE) primary cell (PCell) carrier, an UL grant that indicates a permission for a PUSCH transmission on an LTE in Unlicensed (LTE-U) secondary cell (SCell) carrier during one or more subframes, wherein the LTE PCell carrier is in a licensed frequency spectrum;
determine, at the UE, that the LTE-U SCell carrier is available for transmission during the one or more subframes, wherein the determination that the LTE-U SCell carrier is available for transmission during the one or more subframes comprises measuring a signal level lower than a threshold; and
in response to determining at the UE that the LTE-U SCell carrier is available for transmission:
transmit from the UE, a CTS message on the LTE-U SCell carrier independent of receiving an RTS, wherein the CTS message includes a duration field, the duration field indicating a time period until an end of the one or more subframes, and the CTS message includes a Medium Access Control (MAC) address or a pseudo MAC address associated with the UE; and
transmit a PUSCH subframe on the LTE-U SCell carrier during the time period indicated by the duration field.