Signaling TA-offset in NR
A method performed by a wireless device for determining a timing advance (TA) offset in a new radio (NR) network is described herein along with associated network devices and systems. An exemplary method includes obtaining an indication of whether a carrier frequency of the NR network coexists with a carrier frequency of a long term evolution (LTE) network, determining, based on whether the carrier frequency of the NR network coexists with carrier frequency of the LTE network, a TA offset for uplink transmission; and transmitting an uplink transmission using the determined TA offset.
1 . A method performed by a wireless device for determining a timing advance (TA) offset in a new radio (NR) network, the method comprising:
obtaining, by broadcast signaling from a network node, an indication of whether a carrier frequency of the NR network coexists with a carrier frequency of a long term evolution (LTE) network;
determining, based on the indication obtained by broadcast signalling from the network node, a TA offset for uplink transmission; and
transmitting an uplink transmission using the determined TA offset.
2 . The method of claim 1 , wherein the TA offset depends on a duplex mode of the frequency band of the carrier frequency of the NR network that coexists with the carrier frequency of the LTE network.
3 . The method of claim 1 , wherein:
the signaling includes an explicit TA offset value; and
determining the TA offset comprises using the received explicit TA offset value.
4 . The method of claim 1 , wherein the carrier frequency of the NR network is not a time division duplex (TDD) network and the TA offset is equal to zero.
5 . The method of claim 1 , wherein the NR network is a time division duplex (TDD) network, the carrier frequency of the NR network is below a threshold value, the NR network does not coexist with an LTE network, and the TA offset is equal to a first value greater than 0.
6 . The method of claim 1 , wherein the NR network is a time division duplex (TDD) network, the carrier frequency of the NR network is above a threshold value, the NR network does not coexist with an LTE network, and the TA offset is equal to a second value greater than 0.
7 . The method of claim 1 , wherein the NR network is a time division duplex (TDD) network, the carrier frequency of the NR network is above a threshold value, the NR network coexists with an LTE network, and the TA offset is equal to a third value greater than 0.
8 . The method of claim 1 , wherein the uplink transmission is a random access to a cell on the carrier frequency of the NR network.
9 . The method of claim 1 , wherein the TA offset relates uplink transmission timing with respect to downlink transmission timing in a cell belonging to the carrier frequency of the NR network.
10 . A method performed by a network node for signaling a timing advance (TA) offset to a wireless device in a new radio (NR) network, the method comprising:
sending, in broadcast signalling, an indication of whether the carrier frequency of the NR network coexists with a carrier frequency of a long term evolution (LTE) network, which the wireless device uses to determine a timing advance (TA) offset for a carrier frequency of the NR network to the wireless device; and
receiving an uplink transmission sent by the wireless device using the TA offset.
11 . The method of claim 10 , wherein the TA offset depends on a duplex mode of the frequency band of the carrier frequency of the NR network that coexists with the carrier frequency of the LTE network.
12 . The method of claim 11 , wherein the duplex mode is one of: a frequency division duplex (FDD) and a time division duplex (TDD).
13 . The method of claim 10 , wherein the indication of the timing offset comprises an explicit indication of an amount of time.
14 . The method of claim 13 , wherein the NR network is not a time division duplex (TDD) network and the TA offset is equal to zero.
15 . The method of claim 13 , wherein the NR network is a time division duplex (TDD) network, the carrier frequency of the NR network is below a threshold value, the NR network does not coexist with an LTE network, and the TA offset is equal to a first value greater than 0.
16 . The method of claim 10 , wherein the indication of the timing offset comprises an indication of whether the carrier frequency of the NR network coexists with an LTE network.
17 . The method of claim 10 , wherein the uplink transmission is a random access to a cell on the carrier frequency of the NR network.
18 . The method of claim 10 , wherein the TA offset relates uplink transmission timing with respect to downlink transmission timing in a cell belonging to the carrier frequency of the NR network.
19 . A wireless device for determining a timing advance (TA) offset in a new radio (NR) network, the wireless device comprising:
processing circuitry configured to perform operations comprising:
obtaining, via broadcast signaling from a network node, an indication of whether the NR network is a time division duplex (TDD) network, a carrier frequency of the NR network, and whether the NR network coexists with a long term evolution (LTE) network,
determining, based on indication, a TA offset for uplink transmission, and
transmitting an uplink transmission using the determined TA offset; and
power supply circuitry configured to supply power to the wireless device.