US 12,035,364 B2
Secondary cell activation mechanism in the new radio unlicensed spectrum
Xiang Chen, Campbell, CA (US); Dawei Zhang, Saratoga, CA (US); Huaning Niu, San Jose, CA (US); Jie Cui, San Jose, CA (US); Manasa Raghavan, Sunnyvale, CA (US); Qiming Li, Beijing (CN); and Yang Tang, San Jose, CA (US)
Assigned to Apple Inc., Cupertino, CA (US)
Appl. No. 17/437,784
Filed by Apple Inc., Cupertino, CA (US)
PCT Filed Mar. 31, 2021, PCT No. PCT/CN2021/084343
§ 371(c)(1), (2) Date Dec. 8, 2021,
PCT Pub. No. WO2022/205048, PCT Pub. Date Oct. 6, 2022.
Prior Publication US 2022/0417990 A1, Dec. 29, 2022
Int. Cl. H04W 74/0808 (2024.01)
CPC H04W 74/0808 (2013.01) 20 Claims
OG exemplary drawing
 
1. An apparatus, comprising:
a memory; and
at least one processor in communication with the memory, wherein the at least one processor is configured to:
receive a media access control (MAC) control element (CE) from a base station (BS) indicating a secondary cell (SCell) to be activated in an unlicensed band;
initiate, in response to receiving the MAC CE, a timer with an end value;
adjust a radio-frequency (RF) chain from a first state to a second state, wherein the second state corresponds to the SCell;
determine, based on measurements of one or more synchronization signal blocks (SSBs) transmitted from the BS indicating one or more listen before talk (LBT) failures corresponding to the SCell, one or more failed SSB transmissions corresponding to the Scell;
readjust, in response to expiry of the timer, the RF chain from the second state to the first state; and
receive one or more additional SSBs in the first state.