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EP-3991461-B1 - EARLY DATA TRANSMISSION FOR DUAL CONNECTIVITY OR CARRIER AGGREGATION

EP3991461B1EP 3991461 B1EP3991461 B1EP 3991461B1EP-3991461-B1

Inventors

  • ZIRWAS, WOLFGANG
  • SÄILY, Mikko
  • VIRTEJ, ELENA

Dates

Publication Date
20260513
Application Date
20190628

Claims (11)

  1. A user equipment (402) comprising means for performing: receiving (610) configuration information from a network node; initiating (620) an early data transmission, EDT, random access, RA, procedure with one or more cells indicated in the configuration information, the one or more cells being potential secondary cells for dual connectivity or carrier aggregation at the user equipment; determining (630) a cell (414) of the one or more cells (412, 414) as a preferred secondary cell, the determining based at least on the initiating; and transmitting (640) data to the preferred secondary cell (414).
  2. The user equipment of claim 1, further comprising means for performing: initiating a first early data transmission, EDT, random access, RA, procedure with a first cell of the one or more cells; transmitting, to the first cell, a first cell addition request, the first cell addition request being transmitted as part of Msg3 or MsgA of the first early data transmission, EDT, random access, RA, procedure; and receiving, from the first cell, acceptance of the first cell addition request, the acceptance received as part of Msg4 or MsgB of the first early data transmission, EDT, random access, RA, procedure.
  3. The user equipment of claim 1, further comprising means for performing: initiating a first early data transmission, EDT, random access, RA, procedure with a first cell of the one or more cells; transmitting, to the first cell, a first cell addition request, the first cell addition request being transmitted with Msg3 or MsgA of the first early data transmission, EDT, random access, RA, procedure; receiving, from the first cell, a rejection of the first cell addition request, the rejection received as part of Msg4 or MsgB of the first early data transmission, EDT, random access, RA, procedure; initiating a second early data transmission, EDT, random access, RA, procedure with a second cell of the one or more cells; transmitting, to the second cell, a second cell addition request, the second cell addition request being transmitted as part of Msg3 or MsgA of the second early data transmission, EDT, random access, RA, procedure; and receiving, from the second cell, acceptance of the second cell addition request, the acceptance received as part of Msg4 or MsgB of the second early data transmission, EDT, random access, RA, procedure.
  4. The user equipment of claim 3, further comprising means for performing: updating the configuration information received from the network node by removing the first cell from the configuration information in response to the receiving of the rejection of the first cell addition request.
  5. The user equipment of claim 1, further comprising means for performing: initiating a first early data transmission, EDT, random access, RA, procedure with a first cell of the one or more cells; transmitting, to the first cell, a first cell addition request, the first cell addition request being transmitted with Msg3 or MsgA of the first early data transmission, EDT, random access, RA, procedure; receiving, from the first cell, acceptance of the first cell addition request, the acceptance received as part of Msg4 or MsgB of the first early data transmission, EDT, random access, RA, procedure; transmitting data packets to the first cell; initiating a second early data transmission, EDT, random access, RA, procedure with a second cell of the one or more cells; transmitting, to the second cell, a second cell addition request, the second cell addition request being transmitted as part of Msg3 or MsgA of the second early data transmission, EDT, random access, RA, procedure; receiving, from the second cell, acceptance of the second cell addition request, the acceptance received as part of Msg4 or MsgB of the second early data transmission, EDT, random access, RA, procedure; and performing a handover of the user equipment from the first cell to the second cell.
  6. The user equipment of one of claim 2 or 3, further comprising means for performing: transmitting, to the network node, an indication that the first cell is selected as the preferred secondary cell; or transmitting, to the network node, an indication that the second cell is selected as the preferred secondary cell.
  7. The user equipment of one of claim 2 or 3, wherein the Msg3 and Msg4 of the first and second early data transmission, EDT, random access, RA, procedures are associated with a four-step random access, RA, procedure; or wherein the MsgA and MsgB of the first and second early data transmission, EDT, random access, RA, procedures are associated with a two-step random access, RA, procedure.
  8. The user equipment of claim 1, wherein the configuration information is received by the user equipment when the user equipment is in a radio resource control, RRC)_CONNECTED state.
  9. The user equipment of claim 1, wherein the configuration information is received by the user equipment when the user equipment is in a radio resource control, RRC_IDLE, or radio resource control, RRC_INACTIVE state.
  10. The user equipment of claim 1, wherein the configuration information is received by the user equipment when the user equipment is in a radio resource control, RRC_IDLE, or radio resource control, RRC_INACTIVE state via one or more of: system information, SI; on-demand system information, on-demand SI; and dedicated signaling.
  11. A method of communications, comprising: receiving, by a user equipment, UE, configuration information from a network node; initiating, by the user equipment, UE, an early data transmission, EDT, random access, RA, procedure with one or more cells indicated in the configuration information, the one or more cells being potential secondary cells for dual connectivity or carrier aggregation at the user equipment, UE; determining, by the user equipment, UE, a cell of the one or more cells as a preferred secondary cell, the determining based at least on the initiating; and transmitting, by the user equipment, UE, data to the preferred secondary cell.

Description

TECHNICAL FIELD This description relates to wireless communications, and in particular, to configuration of dual connectivity (DC) or carrier aggregation (CA). BACKGROUND A communication system may be a facility that enables communication between two or more nodes or devices, such as fixed or mobile communication devices. Signals can be carried on wired or wireless carriers. An example of a cellular communication system is an architecture that is being standardized by the 3rd Generation Partnership Project (3GPP). A recent development in this field is often referred to as the long-term evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio-access technology. E-UTRA (evolved UMTS Terrestrial Radio Access) is the air interface of 3GPP's Long Term Evolution (LTE) upgrade path for mobile networks. In LTE, base stations or access points (APs), which are referred to as enhanced Node AP or Evolved Node B (eNBs), provide wireless access within a coverage area or cell. In LTE, mobile devices, or mobile stations are referred to as user equipments (UE). LTE has included a number of improvements or developments. 5G New Radio (NR) is part of a continued mobile broadband evolution process to meet the requirements of 5G, similar to earlier evolution of 3G & 4G wireless networks. In addition, 5G is also targeted at the new emerging use cases in addition to mobile broadband. A goal of 5G is to provide significant improvement in wireless performance, which may include new levels of data rate, latency, reliability, and security. 5G NR may also scale to efficiently connect the massive Internet of Things (IoT), and may offer new types of mission-critical services. Ultra-reliable and low-latency communications (URLLC) devices may require high reliability and very low latency. US 2019/159197 discloses a way of configuring a UE for early data transmission (EDT), by encoding a physical random access channel (PRACH) preamble for transmission to a base station as a PRACH procedure Message, the PRACH preamble including a request for EDT, receiving configuration information from the base station as a random-access response (RAR) message including a transmission block size (TBS) indicator. Selecting a TBS from a plurality of available TBSs corresponding to the TBS indicator and encoding UL data as the EDT to the base station. SUMMARY An example method, and user equipment are provided for early data transmission (EDT) random access (RA) procedure for dual connectivity or carrier aggregation. In an example implementation, a user equipment according to claim 1 and a method according to claim 11 are provided. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a wireless network according to an example implementation.FIG. 2 illustrates an inter-frequency deployment scenario, according to at least an example implementation.FIG. 3 illustrates an early data transmission (EDT) random access (RA) procedure for dual connectivity/carrier aggregation, according to at least an example implementation.FIG. 4 is a message flow diagram illustrating early data transmission (EDT) random access (RA) procedure for dual connectivity/carrier aggregation, according to an example implementation.FIG. 5 is a message flow diagram illustrating early data transmission (EDT) random access (RA) procedure for dual connectivity/carrier aggregation, according to an additional example implementation.FIG. 6 is a flow chart illustrating early data transmission (EDT) random access (RA) procedure for dual connectivity/carrier aggregation, according to at least one example implementation.FIG. 7 is a block diagram of a node or wireless station (e.g., base station/access point or mobile station/user device/UE), according to an example implementation. DETAILED DESCRIPTION FIG. 1 is a block diagram of a wireless network 130 according to an example implementation. In the wireless network 130 of FIG. 1, user devices (UDs) 131, 132, 133 and 135, which may also be referred to as mobile stations (MSs) or user equipment (UEs), may be connected (and in communication) with a base station (BS) 134, which may also be referred to as an access point (AP), an enhanced Node B (eNB) or a network node. At least part of the functionalities of an access point (AP), base station (BS) or (e)Node B (eNB) may also be carried out by any node, server or host which may be operably coupled to a transceiver, such as a remote radio head. BS (or AP) 134 provides wireless coverage within a cell 136, including to user devices 131, 132, 133 and 135. Although only four user devices are shown as being connected or attached to BS 134, any number of user devices may be provided. BS 134 is also connected to a core network 150 via a S1 interface 151. This is merely one simple example of a wireless network, and others may be used. A user device (user terminal, user equipment (UE)) may refer to a portable computing device that includes wireless mobile communication devices operating wi