Method and apparatus for timing management in communication system
AssigneeElectronics and Telecommunications Research Institute
InventorJi Hyung Kim
Life of this patent
Estimating the term…
Abstract
An operation method of a terminal may comprise: receiving information on a common delay time between the terminal and the base station and information on a PRACH occasion through a service link established between the terminal and the satellite; calculating a first adjustment value based on the common delay time; transmitting a PRACH preamble through the service link at a first timing earlier by the first adjustment value than the PRACH occasion; receiving a random access response (RAR); calculating a second adjustment value based on the common delay time; and transmitting an uplink signal through the service link at a second timing later by the second adjustment value than the response delay time.
Claims12
A method of a terminal, the method comprising:
- receiving a timing drift rate from a base station;
- receiving information of a common delay time between a plurality of terminals and the base station from the base station;
- transmitting a random access (RA) preamble at a time determined based on the common delay time to the base station;
- monitoring to receive a random access response (RAR) in response to the RA preamble from the base station within a window starting after an offset time which is determined based on a delay parameter between the terminal and a satellite;
- obtaining a timing advance (TA) value from the base station;
- updating the TA value based on the timing drift rate and an ephemeris of the satellite;
- calculating a difference value between the TA value and the updated TA value;
- transmitting information of the updated TA value which is the difference value to the base station;
- performing an uplink communication with the base station based on the updated TA value;
- receiving a medium access control (MAC) control element (CE) including additional update information of the updated TA value from the base station;
- further updating the updated TA value based on the additional update information;
- and
- performing an uplink communication with the base station based on the further updated TA value.
A method of a base station, the method comprising:
- transmitting a timing drift rate to a terminal;
- transmitting information of a common delay time between a plurality of terminals and the base station to the terminal;
- transmitting an ephemeris of a satellite to the terminal;
- receiving a random access (RA) preamble at a time determined based on the common delay time from the terminal;
- transmitting a random access response (RAR) in response to the RA preamble to the terminal within a window starting after an offset time which is determined based on a delay parameter between the terminal and the satellite;
- receiving information of an updated timing advance (TA) value based on the timing drift rate and the ephemeris from the terminal;
- performing an uplink communication with the terminal based on the updated TA value;
- transmitting a medium access control (MAC) control element (CE) including additional update information of the updated TA value to the terminal;
- and
- performing an uplink communication with the terminal based on a further updated TA value determined by the additional update information,
- wherein the information of the updated TA value is a difference value between a TA value and the updated TA value, and the TA value is transmitted from the base station to the terminal in an initial access procedure between the terminal and the base station.
Dependencies are inferred from the claim text.