Managing data communication in a distributed base station
A DU and/or a CU of a distributed base station implement the techniques of this disclosure to support early data transmission from a UE operating in an inactive or idle state. In some embodiments, the DU receives ( 304 ) a MAC PDU from the UE when the radio connection between the UE and the DU is not active ( 302 ). The DU provides ( 308 ) the data packet included in the MAC PDU to the CU while preventing ( 306 ) the CU from initiating a procedure for resuming the radio connection. In this manner, the base station avoids an unnecessary transition of the UE to the connected state. The CU may then proceed with releasing ( 312 ) radio resources or otherwise determining to reactivate the radio connection.
1 . A method, in a central unit (CU) of a distributed base station, for managing data transmission from a user equipment (UE), the method comprising:
receiving, from a distributed unit (DU), a transfer message including (i) an uplink message associated with a protocol for controlling radio resources and related to a UE, the uplink message including an early data transmission (EDT) indication, (ii) a radio configuration for the UE, and (iii) at least a portion of an uplink packet from the UE; and
in response to the uplink message including the EDT indication, refraining from transmitting, to the UE, the radio configuration received from the DU.
2 . The method of claim 1 , the method further including:
discarding the radio configuration in response to determining that the uplink message is a request to set up a new radio connection.
3 . The method of claim 2 , the method further including, when the uplink message is a request to resume a radio connection between the UE and the DU:
performing a context setup procedure to obtain, from the DU, the radio configuration for the UE; and
discarding the radio configuration in response to determining that the transfer message includes the at least the portion of the uplink data packet.
4 . The method of claim 1 , further comprising:
transmitting, to the UE via the DU and subsequently to receiving the at least a portion of the uplink data packet, a release command associated with the protocol for controlling radio resources.
5 . The method of claim 4 , wherein the release command is contained in one of:
(i) a command to release a context for the UE,
(ii) a command to modify a context for the UE, and
(iii) a DL RRC transfer message.
6 . The method of claim 1 , further comprising:
transmitting, to the DU and prior to transmitting a release command, a downlink data packet.
7 . The method of claim 1 , the method further including:
processing the at least the portion of the uplink data packet.
8 . The method of claim 1 , wherein the transfer message is an initial UL RRC message transfer request.
9 . The method of claim 7 , wherein:
the uplink message is a request to resume a radio connection between the UE and the DU;
the method further comprising:
obtaining a UE context for the UE based on the request; and
processing the at least a portion of the uplink data packet in accordance with the UE context.
10 . The method of claim 1 , the method further comprising:
in response to the uplink message including the EDT indication, refraining from performing a context setup procedure for the UE.
11 . A method, in a distributed unit (DU) of a distributed base station, for managing early data transmission (EDT) from a UE, the method comprising:
receiving, when a radio resource control connection between the UE and the DU is not active, one or more messages from the UE; and
transmitting, to a central unit (CU) of the distributed base station, a transfer message including (i) an uplink message associated with a protocol for controlling radio resources and related to a UE, the uplink message including an EDT indication, (ii) a radio configuration for the UE, and (iii) at least a portion of an uplink packet from the UE, while preventing, via the EDT indication, the CU from transmitting, to the UE, the radio configuration received from the DU.
12 . The method of claim 11 , wherein the uplink message is an initial UL RRC message transfer request.
13 . The method of claim 11 , wherein:
the DU operates as an integrated access and mobility (IAB)-node, and
the CU operates as an IAB-donor.
14 . A network node, operating as a central unit (CU) of a distributed base station, configured to manage data transmission from a user equipment (UE), the network node comprising:
a transceiver; and
processing hardware configured to:
receive, from a distributed unit (DU), a transfer message including (i) an uplink message associated with a protocol for controlling radio resources and related to a UE, the uplink message including (ii) an early data transmission (EDT) indication, (ii) a radio configuration for the UE, and (iii) at least a portion of an uplink packet from the UE; and
in response to the uplink message including the EDT indication, refraining from transmitting, to the UE, a radio configuration received from the DU.
15 . The network node of claim 14 , wherein the processing hardware is further configured to:
process the at least the portion of the uplink data packet.
16 . The network node of claim 15 , wherein the processing hardware is further configured to:
discard the radio configuration in response to at least one of: (i) determining that the transfer message includes the uplink message, uplink data, and the radio configuration; or (ii) determining that the uplink message is a request to set up a new radio connection.
17 . The network node of claim 16 , wherein the processing hardware is further configured to, when the uplink message is a request to resume a radio connection between the UE and the DU:
perform a context setup procedure to obtain, from the DU, the radio configuration for the UE; and
discard the radio configuration in response to determining that the transfer message includes the at least the portion of the uplink data packet.
18 . The network node of claim 15 , wherein the processing hardware is further configured to:
transmit, to the UE via the DU and subsequently to receiving the at least a portion of the uplink data packet, a release command associated with a protocol for controlling radio resources.
19 . The network node of claim 15 , wherein the uplink message is a request to resume a radio connection between the UE and the DU, and the processing hardware is further configured to:
obtain a UE context for the UE based on the request; and
process the at least a portion of the uplink data packet in accordance with the UE context.