US 10,560,891 B2
Medium Access Control in LTE-U
Eswar Vutukuri, Hampshire (GB); Takashi Suzuki, Tokyo (JP); Nicholas William Anderson, Warmley (GB); and Zhijun Cai, Herndon, VA (US)
Assigned to BlackBerry Limited, Waterloo, Ontario (CA)
Filed by BlackBerry Limited, Waterloo (CA)
Filed on Sep. 9, 2014, as Appl. No. 14/481,808.
Prior Publication US 2016/0073344 A1, Mar. 10, 2016
Int. Cl. H04W 52/02 (2009.01); H04W 72/14 (2009.01); H04W 76/28 (2018.01)
CPC H04W 52/0216 (2013.01) [H04W 52/0229 (2013.01); H04W 72/14 (2013.01); H04W 76/28 (2018.02)] 12 Claims
OG exemplary drawing
 
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.