US Patent No. 10,743,344

CHANNEL ACCESS METHOD, DEVICE AND SYSTEM IN UNLICENSED BAND


Patent No. 10,743,344
Issue Date August 11, 2020
Title Channel Access Method, Device And System In Unlicensed Band
Inventorship Minseok Noh, Seoul (KR)
Jinsam Kwak, Gyeonggi-do (KR)
Juhyung Son, Gyeonggi-do (KR)
Assignee WILUS INSTITUTE OF STANDARDS AND TECHNOLOGY INC., Gyeonggi-Do (KR)

Claim of US Patent No. 10,743,344

1. A method for a user equipment to perform uplink transmission on a specific cell in a cellular wireless communication system, the method comprising:receiving uplink scheduling information on the uplink transmission including a new data indicator (NDI) associated with a specific subframe in a first uplink transmission burst;
determining a contention window size based on the NDI;
generating a random number N (N?0) in the determined contention window size; and
performing the uplink transmission on the specific cell after sensing a channel on the specific cell at least for N slots while the channel on the specific cell is idle,
wherein the contention window size is determined independently for each of every channel access priority class,
wherein when the NDI is toggled, the NDI associated with the specific subframe indicates a new data transmission, and each of a contention window size for every channel access priority class is reset to a minimum value for each of every channel access priority class, and
wherein when the NDI is not toggled, the NDI associated with the specific subframe indicates a data retransmission, and each of the contention window size for every channel access priority class is increased to a next higher allowed value for each of every channel access priority class.