Fronthaul interface for advanced split-radio access network (RAN) systems

Patent metadata

Field	Value
Publication number	US-11612016-B2
Application number	US-202117169052-A
Country	US
Kind code	B2
Filing date	Feb 5, 2021
Priority date	Feb 5, 2020
Publication date	Mar 21, 2023
Grant date	Mar 21, 2023

Abstract

One embodiment is directed to a system comprising a distributed unit (DU) and a plurality of remote units (RUs) to wirelessly transmit and receive radio frequency signals to and from the user equipment using a wireless interface. The DU and RUs are communicatively coupled to each other over a fronthaul and are configured to communicate over the fronthaul using an O-RAN fronthaul interface. The DU and RUs are configured to communicate O-RAN control-plane and user-plane messages that include a new O-RAN section extension for use in communicating different section data to different RUs. Other embodiments are disclosed.

First claim

What is claimed is:

1. A system comprising:
a distributed unit (DU) to communicatively couple the system to a core network, the DU configured to implement at least some LAYER 2 functions for a wireless interface and at least some LAYER 1 functions for the wireless interface; and
a plurality of remote units (RUs) to wirelessly transmit and receive radio frequency signals to and from user equipment (UE) using the wireless interface in connection with serving a cell, each of the RUs associated with at least one antenna and located remotely from the DU and at least one other RU, wherein each RU is configured to implement the LAYER 1 functions for the wireless interface that are not implemented in the DU;
wherein the DU and RUs are communicatively coupled to each other over a fronthaul and are configured to communicate over the fronthaul using an Open Radio Access Network (O-RAN) fronthaul interface; and
wherein the DU is configured to do the following in connection with wirelessly transmitting user data to a UE using less than all of the RUs:
include, in a control-plane message for that UE that is communicated over the fronthaul, section fields that include a predetermined section extension; and
include, in one or more user-plane messages for that UE that are communicated over the fronthaul and that are associated with the control-plane message for that UE, section fields that include the predetermined section extension;

wherein each control-plane message that includes the predetermined section extension and the associated one or more user-plane messages include common header fields that contain a RU mask field for storing a bit mask comprising a plurality of bit positions, wherein each bit position is associated with a respective one of the RUs;
wherein each RU is configured to:
use the RU mask field included in any control-plane or user-plane message received by that RU that includes the predetermined section extension in order to determine if the received control-plane or user-plane message is intended for that RU;
use the received control-plane or user-plane message to wirelessly transmit the user data to that UE using that RU, if the RU mask field indicates that the received control-plane or user-plane message is intended for that RU; and
discard the received control-plane or user-plane message, if the RU mask field indicates that the received control-plane message is not intended for that RU.

2. The system of claim 1 , wherein the system is configured to simultaneously wirelessly transmit respective user data to multiple UEs using the same physical resource blocks, wherein the respective user data simultaneously wirelessly transmitted to the multiple UEs using the same physical resource blocks is wirelessly transmitted from respective subsets of the RUs, wherein none of the subsets of the RUs contain the same RU;
wherein the DU is configured to do the following in connection with simultaneously wirelessly transmitting the respective user data to the multiple UEs using the same physical resource blocks:
include, in a control-plane message for each of the multiple UEs that is communicated over the fronthaul, respective section fields for that UE that include the predetermined section extension; and
include, in one or more user-plane messages for each of the multiple UEs that are communicated over the fronthaul and that are associated with the control-plane message for that UE, respective section fields that include the predetermined section extension.

3. The system of claim 1 , wherein the system is configured so that the predetermined section extension includes fields for storing different beamforming information for each RU used to wirelessly transmit user-data to an associated UE.

4. The system of claim 1 , wherein the system is configured to communicate, over the fronthaul, control-plane and user-plane messages including the predetermined section extension in one of an unbundled mode or a bundled mode.

5. The system of claim 1 , wherein the system is configured to communicate, over the fronthaul, control-plane and user-plane messages including the predetermined section extension in connection with fully simulcasting user data to a UE, wherein the user data is wirelessly transmitted from all the RUs to said UE.

6. A method for use in a system comprising:
a distributed unit (DU) to communicatively couple the system to a core network, the DU configured to implement at least some LAYER 2 functions for a wireless interface and at least some LAYER 1 functions for the wireless interface; and
a plurality of remote units (RUs) to wirelessly transmit and receive radio frequency signals to and from user equipment (UE) using the wireless interface in connection with serving a cell, each of the RUs associated with at least one antenna and located remotely from the DU and at least one other RU, wherein each RU is configured to implement the LAYER 1 functions for the wireless interface that are not implemented in the DU;
wherein the DU and RUs are communicatively coupled to each other over a fronthaul and are configured to communicate over the fronthaul using an Open Radio Access Network (O-RAN) fronthaul interface; and
wherein the DU is configured to do the following in connection with wirelessly transmitting user data to a UE using less than all of the RUs:
include, in a control-plane message for that UE that is communicated over the fronthaul, section fields that include a predetermined section extension; and
include, in one or more user-plane messages for that UE that are communicated over the fronthaul and that are associated with the control-plane message for that UE, section fields that include the predetermined section extension;

wherein each control-plane message that includes the predetermined section extension and the associated one or more user-plane messages include common header fields that contain a RU mask field for storing a bit mask comprising a plurality of bit positions, wherein each bit position is associated with a respective one of the RUs;
wherein the method comprises doing the following at each RU:
using the RU mask field included in any control-plane or user-plane message received by that RU that includes the predetermined section extension in order to determine if the received control-plane or user-plane message is intended for that RU;
using the received control-plane or user-plane message to wirelessly transmit the user data to that UE using that RU, if the RU mask field indicates that the received control-plane or user-plane message is intended for that RU; and
discarding the received control-plane or user-plane message, if the RU mask field indicates that the received control-plane message is not intended for that RU.

7. The method of claim 6 , wherein the system is configured to simultaneously wirelessly transmit respective user data to multiple UEs using the same physical resource blocks, wherein the respective user data simultaneously wirelessly transmitted to the multiple UEs using the same physical resource blocks is wirelessly transmitted from respective subsets of the RUs, wherein none of the subsets of the RUs contain the same RU;
wherein the DU is configured to do the following in connection with simultaneously wirelessly transmitting the respective user data to the multiple UEs using the same physical resource blocks:
include, in a control-plane message for each of the multiple UEs that is communicated over the fronthaul, respective section fields for that UE that include the predetermined section extension; and
include, in one or more user-plane messages for each of the multiple UEs that are communicated over the fronthaul and that are associated with the control-plane message for that UE, respective section fields that

Assignees

• Commscope Technologies Llc

Inventors

• Raghothaman Balaji B
• Armao Calogero
• Salahuddeen Irfaan Ahamed

Classifications

• H04W28/0289

  Congestion control (load shedding arrangements in network planning H04W16/08; performing reselection for handling the traffic H04W36/22; wireless traffic scheduling H04W72/12) · CPC title

• H04W92/20

  between access points · CPC title

• H04W92/12

  between access points and access point controllers · CPC title

• H04W88/085 Primary

  Access point devices with remote components · CPC title

• H04B7/043

  using best eigenmode, e.g. beam forming or beam steering · CPC title