Timing advance for satellite-based communications
Various arrangements are presented for using an estimated timing advance for user equipment communications. A location of an instance of user equipment may be determined. A first estimated distance between the user equipment and a communication satellite may be determined using the determined location of the user equipment and an estimated satellite location. A second estimated distance between the communication satellite and a communication network gateway may be determined. An estimated timing offset using the calculated first estimated distance and the determined second estimated distance may be determined. An uplink data frame may be transmitted by the user equipment to the satellite such that a timing of transmission of the uplink data frame is based on the calculated estimated timing offset.
1. A method for using an estimated timing advance for user equipment communications, the method comprising:
determining, by a user equipment (UE), a first estimated distance between a communication satellite and a communication network gateway by accessing the first estimated distance from a data storage arrangement of the UE;
calculating a second estimated distance between the user equipment and the communication satellite using a location of the UE and an estimated location of the communication satellite;
calculating a total distance estimate from the UE to the communication network gateway using the first estimated distance and the second estimated distance;
calculating an estimated timing offset using the total distance estimate from the UE to the communication network gateway;
transmitting, by the UE, to the communication satellite, first data such that a timing of transmission of the first data is based on the calculated estimated timing offset;
after transmitting the first data such that the timing of the transmission of the first data is based on the calculated timing offset, receiving, by the UE, a timing advance (TA) command that comprises a TA value;
adjusting, by the UE, the calculated estimated timing offset based on the received TA value to create a corrected TA value; and
transmitting, by the UE, to the communication satellite, second data such that a timing of transmission of the second data is based on the corrected TA value.
2. The method for using the estimated timing advance for the user equipment communications of claim 1 , wherein the first data transmitted to the communication satellite comprises a physical random access channel (PRACH) preamble.
3. The method for using the estimated timing advance for the user equipment communications of claim 1 , further comprising:
determining, by the communication network gateway, an amount of timing error in the timing of the transmission of the first data;
determining, by the communication network gateway, the TA value based on the amount of timing error; and
transmitting, by the communication network gateway, the TA command that comprises the TA value to the user equipment via the communication satellite.
4. The method for using the estimated timing advance for the user equipment communications of claim 1 , wherein the communication satellite is in geosynchronous orbit of the earth.
5. The method for using the estimated timing advance for the user equipment communications of claim 1 , further comprising:
accessing locally-stored orbital information of the communication satellite, wherein the communication satellite is in low earth orbit (LEO) or middle earth orbit (MEO); and
calculating the estimated satellite location based on the locally-stored orbital information.
6. The method for using the estimated timing advance for the user equipment communications of claim 1 , wherein the communication network gateway comprises a gNodeB.
7. A device for using an estimated timing advance for satellite-based communications, the device comprising:
a satellite antenna for communicating directly with a communication satellite that relays communications to a satellite gateway system;
one or more processors in communication with the satellite antenna, the one or more processors configured to:
determine a first estimated distance between the communication satellite and the satellite gateway system by accessing the first estimated distance from a data storage arrangement of the device;
calculate a second estimated distance between the device and the communication satellite using a location of the device and an estimated location of the communication satellite;
calculate a total distance estimate from the device to the satellite gateway system using the first estimated distance and the second estimated distance;
calculate an estimated timing offset using the total distance estimate from the device to the satellite gateway system;
transmit to the communication satellite using the satellite antenna, first data such that a timing of transmission of the first data is based on the calculated estimated timing offset;
after transmitting the first data such that the timing of the transmission of the first data is based on the calculated timing offset, receive a timing advance (TA) command that comprises a TA value from the communication satellite using the satellite antenna;
adjust the calculated estimated timing offset based on the received TA value to create a corrected TA value; and
transmit, to the communication satellite using the satellite antenna, second data such that a timing of transmission of the second data is based on the corrected TA value.
8. The device of claim 7 , further comprising a global navigation satellite system (GNSS) component, wherein the one or more processors are further configured to:
determine the location of the device using the GNSS component.
9. A system for using an estimated timing advance for satellite-based communications, the system comprising:
a communication satellite;
a communication network gateway system that communicates with the communication satellite; and
user equipment (UE), comprising:
a satellite antenna for communicating with the communication satellite that relays communications to the communication network gateway system; and
one or more processors in communication with the satellite antenna, the one or more processors configured to:
determine a first estimated distance between the communication satellite and the communication network gateway by accessing the first estimated distance from a data storage arrangement of the UE;
calculate a second estimated distance between the user equipment and the communication satellite using a location of the UE and an estimated location of the communication satellite;
calculate a total distance estimate from the UE to the communication network gateway using the first estimated distance and the second estimated distance;
calculate an estimated timing offset using the total distance estimate from the UE to the communication network gateway;
transmit to the communication satellite using the satellite antenna, first data such that a timing of transmission of the first data is based on the calculated estimated timing offset;
after transmitting the first data such that the timing of the transmission of the first data is based on the calculated timing offset, receive a timing advance (TA) command that comprises a TA value from the communication satellite using the satellite antenna;
adjust the calculated estimated timing offset based on the received TA value to create a corrected TA value; and
transmit, to the communication satellite using the satellite antenna, second data such that a timing of transmission of the second data is based on the corrected TA value.
10. The system of claim 9 , wherein the communication network gateway system is configured to:
determine an amount of timing error;
determine the timing advance (TA) value based on the amount of timing error; and
transmit the TA command that comprises the TA value to the user equipment.
11. The system of claim 10 , wherein the communication network gateway comprises a gNodeB.