EP4674188A1

EP4674188A1 - Distributed antenna system (das) enhanced energy saving optimization

Info

Publication number: EP4674188A1
Application number: EP24764587.2A
Authority: EP
Inventors: Arjun NANJUNDAPPA; Stuart D. Sandberg; Ehsan Daeipour; Suresh N. SRIRAM
Original assignee: Outdoor Wireless Networks LLC
Current assignee: Outdoor Wireless Networks LLC
Priority date: 2023-03-02
Filing date: 2024-02-29
Publication date: 2026-01-07
Also published as: WO2024182592A1

Abstract

A distributed antenna system is directly connected to a service, management, and orchestrator (SMO) entity via one or more interfaces. The distributed antenna system includes one or more nodes and is configured to provide one or more operational parameters and/or one or more activity parameters for the one or more nodes to the SMO entity. The SMO entity is configured to determine configuration parameters for the distributed antenna system based on at least the one or more operational and/or activity parameters provided by the distributed antenna system. In doing so, the distributed antenna system is configured to implement at least one energy saving policy defined by the configuration parameters.

Description

DISTRIBUTED ANTENNA SYSTEM (DAS) ENHANCED ENERGY SAVING

OPTIMIZATION

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to India Provisional Application Serial No. 202341014065, filed on March 2, 2023, and titled “DISTRIBUTED ANTENNA SYSTEM (DAS) ENHANCED ENERGY SAVING OPTIMIZATION,” the contents of which are incorporated herein in their entirety.

BACKGROUND

[0002] A distributed antenna system (DAS) typically includes one or more master units that are communicatively coupled to a plurality of remotely located access points or antenna units (also referred to here as “radio units”), where each access point can be coupled directly to one or more of the master units or indirectly via one or more other remote units and/or via one or more intermediary or expansion units or nodes. A DAS is typically used to improve the coverage provided by one or more base stations that are coupled to the central access nodes. These base stations can be coupled to the one or more master units via one or more cables or via a wireless connection, for example, using one or more donor antennas. The wireless service provided by the base stations can include commercial cellular service and/or private or public safety wireless communications. A DAS is typically utilized by multiple carriers providing wireless service, in which each carrier provides wireless signals in one or more coverage areas supported by the DAS.

[0003] A DAS is coupled to a radio access network (RAN) in order to extend the wireless coverage provided by the RAN. Typically, a DAS (and its individual nodes) is not visible to management plane (M-plane) functionality of the RAN that the DAS is coupled to. Therefore, any M-plane functionalities such as energy usage policies implemented by the RAN would not extend to the nodes of the DAS.

SUMMARY

[0004] The details of one or more embodiments are set forth in the description below. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Thus, any of the various embodiments described herein can be combined to provide further embodiments. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications as identified herein to provide yet further embodiments.

[0005] In one embodiment, a method for reducing energy consumption in a distributed antenna system (DAS) is disclosed. The DAS includes at least one master unit communicatively coupled to a plurality of radio units. The at least one master unit is configured to receive downlink signals from at least one base station entity and to generate downlink transport signals from the downlink signals. The plurality of radio units is configured to radiate radio frequency (RF) signals based on the downlink transport signals to user equipment. The method comprises providing, from at least one interface that directly couples the DAS to a service, management, and orchestrator (SMO) entity, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS. The one or more nodes of the DAS includes at least one of: the at least one master unit or at least one of the plurality of radio units. The method comprises receiving, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the at least one operational parameter and/or the at least one activity parameter of the one or more nodes. The at least one configuration parameter represents a change in operation configuration for the one or more nodes. The method comprises configuring the one or more nodes based on the at least one configuration parameter.

[0006] In another embodiment, a system is disclosed. The system comprises a distributed antenna system (DAS) directly coupled to a service, management, and orchestration (SMO) entity via one or more interfaces. The DAS comprises at least one master unit. The at least one master unit is configured to receive downlink signals from at least one base station entity and to generate downlink transport signals from the downlink signals. The DAS comprises a plurality of radio units communicatively coupled to the at least one master unit. The plurality of radio units is configured to radiate radio frequency (RF) signals based on the downlink transport signals to user equipment. The DAS is configured to provide, from the at least one interface, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS. The one or more nodes of the DAS includes at least one of: the at least one master unit or at least one of the plurality of radio units. The DAS is configured to receive, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the at least one operational parameter and/or the at least one activity parameter of the one or more nodes. The at least one configuration parameter represents a change in operation configuration for the one or more nodes. The DAS is configured to configure the one or more nodes based on the at least one configuration parameter.

[0007] In yet another embodiment, a program product comprises a non-transitory processor-readable medium on which program instructions, configured to be executed by at least one processor, are embodied. When executed by the at least one processor, the program instructions cause the at least one processor to provide, from at least one interface that directly couples a distributed antenna system (DAS) to a service, management, and orchestrator (SMO) entity, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS. The one or more nodes of the DAS includes at least one of: at least one master unit or at least one of a plurality of radio units. The program instructions cause the at least one processor to receive, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the operational parameters and/or activity parameters of the one or more nodes. The at least one configuration parameter represents a change in operation configuration for the one or more nodes. The program instructions cause the at least one processor to configure the one or more nodes based on the at least one configuration parameter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Understanding that the drawings depict only exemplary embodiments and are not therefore to be considered limiting in scope, the exemplary embodiments will be described with additional specificity and detail through the use of the accompanying drawings, as briefly described below and as described further in the detailed description.

[0009] Figures 1-4 depict block diagrams of distributed antenna systems configured to extend wireless coverage of a radio access network, as described in one or more embodiments. [0010] Figure 5 depicts an exemplary system configured to implement one or more energy saving policies, as described in one or more embodiments.

[0011] Figure 6 depicts a block diagram of an exemplary DAS configured for implementing energy saving policies determined by an SMO, as described in one or more embodiments.

[0012] Figure 7 depicts a message flow diagram illustrating communication between components of the system of Figure 5, as described in one or more embodiments.

[0013] Figure 8 depicts a message flow diagram illustrating an exemplary energy saving policy for setting a carrier inactive, as described in one or more embodiments.

[0014] Figure 9 depicts a message flow diagram illustrating an exemplary energy saving policy for setting radio units in a cell inactive, as described in one or more embodiments.

[0015] Figure 10 depicts a flow diagram of an exemplary method for configuring nodes of a DAS based on at least one energy saving policy, as described in one or more embodiments.

[0016] In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the exemplary embodiments.

DETAILED DESCRIPTION

[0017] In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific illustrative embodiments. However, it is to be understood that other embodiments may be utilized and that logical, mechanical, and electrical changes may be made. Furthermore, any methods presented in the drawing figures and the specification are not to be construed as limiting the order in which the individual steps may be performed. The following detailed description is, therefore, not to be taken in a limiting sense.

[0018] A RAN is responsible for a major part of the energy consumption of a mobile network, and the DAS, in particular the radio units, account for the largest contributor of the energy consumption of the RAN. Exemplary embodiments of the present invention include a DAS that coordinates information about performance and activity of the various nodes of the DAS directly with an SMO responsible for determining energy saving policies. Doing so enables energy saving policies to account for DAS activity and performance in real-time, as well as for other parameters used by the RAN, when determining an appropriate energy saving policy, and can be dynamically implemented as the DAS updates the RAN with additional information. Additionally, the DAS can facilitate and execute energy saving policies by configuring one or more nodes based on the energy saving policies set forth by the RAN.

[0019] Figure l is a block diagram illustrating an exemplary embodiment of a distributed antenna system (DAS) 100 that is configured to serve one or more base stations 102. The DAS 100 described in Figure 1, and the DAS 100 described in Figures 2-4, are exemplary DAS systems that can be implemented as part of the RAN architecture described in Figure 5. In the exemplary embodiment shown in Figure 1, the DAS 100 includes one or more donor units 104 that are used to couple the DAS 100 to the base stations 102. The DAS 100 also includes a plurality of remotely located radio units (RUs) 106 (also referred to as “antenna units,” “access points,” “remote units,” or “remote antenna units”). The RUs 106 are communicatively coupled to the donor units 104.

[0020] Each RU 106 includes, or is otherwise associated with, a respective set of coverage antennas 108 via which downlink analog RF signals can be radiated to user equipment (UEs) 110 and via which uplink analog RF signals transmitted by UEs 110 can be received. The DAS 100 is configured to serve each base station 102 using a respective subset of RUs 106 (which may include less than all of the RUs 106 of the DAS 100). Also, the subsets of RUs 106 used to serve the base stations 102 may differ from base station 102 to base station 102. The subset of RUs points 106 used to serve a given base station 102 is also referred to here as the “simulcast zone” for that base station 102. In general, the wireless coverage of a base station 102 served by the DAS 100 is improved by radiating a set of downlink RF signals for that base station 102 from the coverage antennas 108 associated with the multiple RUs 106 in that base station’s stations simulcast zone and by producing a single “combined” set of uplink base station signals or data that is provided to that base station 102. The single combined set of uplink base station signals or data is produced by a combining or summing process that uses inputs derived from the uplink RF signals received via the coverage antennas 108 associated with the RUs 106 in that base station’s simulcast zone.

[0021] The DAS 100 can also include one or more intermediary combining nodes (ICNs) 112 (also referred to as “expansion” units or nodes). For each base station 102 served by a given ICN 112, the ICN 112 is configured to receive a set of uplink transport data for that base station 102 from a group of “southbound” entities (that is, from RUs 106 and/or other ICNs 112) and generate a single set of combined uplink transport data for that base station 102, which the ICN 112 transmits “northbound” towards the donor unit 104 serving that base station 102. The single set of combined uplink transport data for each served base station 102 is produced by a combining or summing process that uses inputs derived from the uplink RF signals received via the coverage antennas 108 of any southbound RUs 106 included in that base station’s simulcast zone. As used here, “southbound” refers to traveling in a direction “away,” or being relatively “farther,” from the donor units 104 and base stations 102, and “northbound” refers to traveling in a direction “towards”, or being relatively “closer” to, the donor units 104 and base stations 102.

[0022] In some configurations, each ICN 112 also forwards downlink transport data to the group of southbound RUs 106 and/or ICNs 112 served by that ICN 112. Generally, ICNs 112 can be used to increase the number of RUs 106 that can be served by the donor units 104 while reducing the processing and bandwidth load relative to having the additional RUs 106 communicate directly with each such donor unit 104.

[0023] Also, one or more RUs 106 can be configured in a “daisy-chain” or “ring” configuration in which transport data for at least some of those RUs 106 is communicated via at least one other RU 106. Each RU 106 would also perform the combining or summing process for any base station 102 that is served by that RU 106 and one or more of the southbound entities subtended from that RU 106. (Such a RU 106 also forwards northbound all other uplink transport data received from its southbound entities.)

[0024] The DAS 100 can include various types of donor units 104. One example of a donor unit 104 is an RF donor unit 114 that is configured to couple the DAS 100 to a base station 116 using the external analog radio frequency (RF) interface of the base station 116 that would otherwise be used to couple the base station 116 to one or more antennas (if the DAS 100 were not being used). This type of base station 116 is also referred to here as an “RF-interface” base station 116. An RF-interface base station 116 can be coupled to a corresponding RF donor unit 114 by coupling each antenna port of the base station 116 to a corresponding port of the RF donor unit 114.

[0025] Each RF donor unit 114 serves as an interface between each served RF- interface base station 116 and the rest of the DAS 100 and receives downlink base station signals from, and outputs uplink base station signals to, each served RF- interface base station 116. Each RF donor unit 114 performs at least some of the conversion processing necessary to convert the base station signals to and from the digital fronthaul interface format natively used in the DAS 100 for communicating time-domain baseband data. The downlink and uplink base station signals communicated between the RF-interface base station 116 and the donor unit 114 are analog RF signals. Also, in this example, the digital fronthaul interface format natively used in the DAS 100 for communicating time-domain baseband data can comprise the 0-RAN fronthaul interface, a CPRI or enhanced CPRI (eCPRI) digital fronthaul interface format, or a proprietary digital fronthaul interface format (though other digital fronthaul interface formats can also be used).

[0026] Another example of a donor unit 104 is a digital donor unit that is configured to communicatively couple the DAS 100 to a baseband entity using a digital baseband fronthaul interface that would otherwise be used to couple the baseband entity to a radio unit (if the DAS 100 were not being used). In the example shown in Figure 1, two types of digital donor units are shown.

[0027] The first type of digital donor unit comprises a digital donor unit 118 that is configured to communicatively couple the DAS 100 to a baseband unit (BBU) 120 using a time-domain baseband fronthaul interface implemented in accordance with a Common Public Radio Interface (“CPRI”) specification. This type of digital donor unit 118 is also referred to here as a “CPRI” donor unit 118, and this type of BBU 120 is also referred to here as a CPRI BBU 120. For each CPRI BBU 120 served by a CPRI donor unit 118, the CPRI donor unit 118 is coupled to the CPRI BBU 120 using the CPRI digital baseband fronthaul interface that would otherwise be used to couple the CPRI BBU 120 to a CPRI remote radio head (RRH) (if the DAS 100 were not being used). A CPRI BBU 120 can be coupled to a corresponding CPRI donor unit 118 via a direct CPRI connection.

[0028] Each CPRI donor unit 118 serves as an interface between each served CPRI BBU 120 and the rest of the DAS 100 and receives downlink base station signals from, and outputs uplink base station signals to, each CPRI BBU 120. Each CPRI donor unit 118 performs at least some of the conversion processing necessary to convert the CPRI base station data to and from the digital fronthaul interface format natively used in the DAS 100 for communicating time-domain baseband data. The downlink and uplink base station signals communicated between each CPRI BBU 120 and the CPRI donor unit 118 comprise downlink and uplink fronthaul data generated and formatted in accordance with the CPRI baseband fronthaul interface.

[0029] The second type of digital donor unit comprises a digital donor unit 122 that is configured to communicatively couple the DAS 100 to a BBU 124 using a frequencydomain baseband fronthaul interface implemented in accordance with a O-RAN Alliance specification. The acronym “O-RAN” is an abbreviation for “Open Radio Access Network.” This type of digital donor unit 122 is also referred to here as an “O- RAN” donor unit 122, and this type of BBU 124 is typically an O-RAN distributed unit (DU) and is also referred to here as an O-RAN DU 124. For each O-RAN DU 124 served by a O-RAN donor unit 122, the O-RAN donor unit 122 is coupled to the O-DU 124 using the O-RAN digital baseband fronthaul interface that would otherwise be used to couple the O-RAN DU 124 to a O-RAN RU (if the DAS 100 were not being used). An O-RAN DU 124 can be coupled to a corresponding O-RAN donor unit 122 via a switched Ethernet network. Alternatively, an O-RAN DU 124 can be coupled to a corresponding O-RAN donor unit 122 via a direct Ethernet or CPRI connection.

[0030] Each O-RAN donor unit 122 serves as an interface between each served O- RAN DU 124 and the rest of the DAS 100 and receives downlink base station signals from, and outputs uplink base station signals to, each O-RAN DU 124. Each O-RAN donor unit 122 performs at least some of any conversion processing necessary to convert the base station signals to and from the digital fronthaul interface format natively used in the DAS 100 for communicating frequency-domain baseband data. The downlink and uplink base station signals communicated between each O-RAN DU 124 and the O-RAN donor unit 122 comprise downlink and uplink fronthaul data generated and formatted in accordance with the O-RAN baseband fronthaul interface, where the user-plane data comprises frequency-domain baseband IQ data. Also, in this example, the digital fronthaul interface format natively used in the DAS 100 for communicating O-RAN fronthaul data is the same O-RAN fronthaul interface used for communicating base station signals between each O-RAN DU 124 and the O- RAN donor unit 122, and the “conversion” performed by each O-RAN donor unit 122 (and/or one or more other entities of the DAS 100) includes performing any needed “multicasting” of the downlink data received from each O-RAN DU 124 to the multiple RUs 106 in a simulcast zone for that O-RAN DU 124 (for example, by communicating the downlink fronthaul data to an appropriate multicast address and/or by copying the downlink fronthaul data for communication over different fronthaul links) and performing any need combining or summing of the uplink data received from the RUs 106 to produce combined uplink data provided to the O-RAN DU 124. It is to be understood that other digital fronthaul interface formats can also be used.

[0031] In general, the various base stations 102 are configured to communicate with a core network (not shown) of the associated wireless operator using an appropriate backhaul network (typically, a public wide area network such as the Internet). Also, the various base stations 102 may be from multiple, different wireless operators and/or the various base stations 102 may support multiple, different wireless protocols and/or RF bands.

[0032] In general, for each base station 102, the DAS 100 is configured to receive a set of one or more downlink base station signals from the base station 102 (via an appropriate donor unit 104), generate downlink transport data derived from the set of downlink base station signals, and transmit the downlink transport data to the RUs 106 in the base station’s simulcast zone. For each base station 102 served by a given RU 106, the RU 106 is configured to receive the downlink transport data transmitted to it via the DAS 100 and use the received downlink transport data to generate one or more downlink analog radio frequency signals that are radiated from one or more coverage antennas 108 associated with that RU 106 for reception by user equipment 110. In this way, the DAS 100 increases the coverage area for the downlink capacity provided by the base stations 102. Also, for any southbound entities (for example, southbound RUs 106 or ICNs 112) coupled to the RU 106 (for example, in a daisy chain or ring architecture), the RU 106 forwards any downlink transport data intended for those southbound entities towards them.

[0033] For each base station 102 served by a given RU 106, the RU 106 is configured to receive one or more uplink radio frequency signals transmitted from the user equipment 110. These signals are analog radio frequency signals and are received via the coverage antennas 108 associated with that RU 106. The RU 106 is configured to generate uplink transport data derived from the one or more remote uplink radio frequency signals received for the served base station 102 and transmit the uplink transport data northbound towards the donor unit 104 coupled to that base station 102.

[0034] For each base station 102 served by the DAS 100, a single “combined” set of uplink base station signals or data is produced by a combining or summing process that uses inputs derived from the uplink RF signals received via the RUs 106 in that base station’s simulcast zone. The resulting final single combined set of uplink base station signals or data is provided to the base station 102. This combining or summing process can be performed in a centralized manner in which the combining or summing process is performed by a single unit of the DAS 100 (for example, a donor unit 104 or master unit 130). This combining or summing process can also be performed in a distributed or hierarchical manner in which the combining or summing process is performed by multiple units of the DAS 100 (for example, a donor unit 104 (or master unit 130) and one or more ICNs 112 and/or RUs 106). Each unit of the DAS 100 that performs the combining or summing process for a given base station 102 receives uplink transport data from that unit’s southbound entities and uses that data to generate combined uplink transport data, which the unit transmits northbound towards the base station 102. The generation of the combined uplink transport data involves, among other things, extracting in-phase and quadrature (IQ) data from the received uplink transport data and performing a combining or summing process using any uplink IQ data for that base station 102 in order to produce combined uplink IQ data.

[0035] Some of the details regarding how base station signals or data are communicated and transport data is produced vary based on which type of base station 102 is being served. In the case of an RF-interface base station 116, the associated RF donor unit 114 receives analog downlink RF signals from the RF- interface base station 116 and, either alone or in combination with one or more other units of the DAS 100, converts the received analog downlink RF signals to the digital fronthaul interface format natively used in the DAS 100 for communicating timedomain baseband data (for example, by digitizing, digitally down-converting, and filtering the received analog downlink RF signals in order to produce digital baseband IQ data and formatting the resulting digital baseband IQ data into packets) and communicates the resulting packets of downlink transport data to the various RUs 106 in the simulcast zone of that base station 116. The RUs 106 in the simulcast zone for that base station 116 receive the downlink transport data and use it to generate and radiate downlink RF signals as described above. In the uplink, either alone or in combination with one or more other units of the DAS 100, the RF donor unit 114 generates a set of uplink base station signals from uplink transport data received by the RF donor unit 114 (and/or the other units of the DAS 100 involved in this process). The set of uplink base station signals is provided to the served base station 116. The uplink transport data is derived from the uplink RF signals received at the RUs 106 in the simulcast zone of the served base station 116 and communicated in packets.

[0036] In the case of a CPRI BBU 120, the associated CPRI digital donor unit 118 receives CPRI downlink fronthaul data from the CPRI BBU 120 and, either alone or in combination with another unit of the DAS 100, converts the received CPRI downlink fronthaul data to the digital fronthaul interface format natively used in the DAS 100 for communicating time-domain baseband data (for example, by resampling, synchronizing, combining, separating, gain adjusting, etc. the CPRI baseband IQ data, and formatting the resulting baseband IQ data into packets), and communicates the resulting packets of downlink transport data to the various RUs 106 in the simulcast zone of that CPRI BBU 120. The RUs 106 in the simulcast zone of that CPRI BBU 120 receive the packets of downlink transport data and use them to generate and radiate downlink RF signals as described above. In the uplink, either alone or in combination with one or more other units of the DAS 100, the CPRI donor unit 118 generates uplink base station data from uplink transport data received by the CPRI donor unit 118 (and/or the other units of the DAS 100 involved in this process). The resulting uplink base station data is provided to that CPRI BBU 120. The uplink transport data is derived from the uplink RF signals received at the RUs 106 in the simulcast zone of the CPRI BBU 120. [0037] In the case of an 0-RAN DU 124, the associated 0-RAN donor unit 122 receives packets of 0-RAN downlink fronthaul data (that is, 0-RAN user-plane and control -plane messages) from each 0-RAN DU 124 coupled to that 0-RAN digital donor unit 122 and, either alone or in combination with another unit of the DAS 100, converts (if necessary) the received packets of 0-RAN downlink fronthaul data to the digital fronthaul interface format natively used in the DAS 100 for communicating O- RAN baseband data and communicates the resulting packets of downlink transport data to the various RUs 106 in a simulcast zone for that ORAN DU 124. The RUs 106 in the simulcast zone of each O-RAN DU 124 receive the packets of downlink transport data and use them to generate and radiate downlink RF signals as described above. In the uplink, either alone or in combination with one or more other units of the DAS 100, the O-RAN donor unit 122 generates packets of uplink base station data from uplink transport data received by the O-RAN donor unit 122 (and/or the other units of the DAS 100 involved in this process). The resulting packets of uplink base station data are provided to the O-RAN DU 124. The uplink transport data is derived from the uplink RF signals received at the RUs 106 in the simulcast zone of the served O-RAN DU 124 and communicated in packets.

[0038] In one implementation, one of the units of the DAS 100 is also used to implement a “master” timing entity for the DAS 100 (for example, such a master timing entity can be implemented as a part of a master unit 130 described below). In another example, a separate, dedicated timing master entity (not shown) is provided within the DAS 100. In either case, the master timing entity synchronizes itself to an external timing master entity (for example, a timing master associated with one or more of the O-DUs 124) and, in turn, that entity serves as a timing master entity for the other units of the DAS 100. A time synchronization protocol (for example, the Institute of Electrical and Electronics Engineers (IEEE) 1588 Precision Time Protocol (PTP), the Network Time Protocol (NTP), or the Synchronous Ethernet (SyncE) protocol) can be used to implement such time synchronization.

[0039] A management system (see e.g., DAS management controller 522 of Figure 5) can be used to manage the various nodes of the DAS 100. In one implementation, the management system communicates with a predetermined “master” entity for the DAS 100 (for example, the master unit 130 described below), which in turns forwards or otherwise communicates with the other units of the DAS 100 for management-plane purposes. In another implementation, the management system communicates with the various nodes of the DAS 100 directly for management-plane purposes (that is, without using a master entity as a gateway).

[0040] Each base station 102 (including each RF-interface base station 116, CPRI BBU 120, and 0-RAN DU 124), donor unit 104 (including each RF donor unit 114, CPRI donor unit 118, and 0-RAN donor unit 122), RU 106, ICN 112, and any of the specific features described here as being implemented thereby, can be implemented in hardware, software, or combinations of hardware and software, and the various implementations (whether hardware, software, or combinations of hardware and software) can also be referred to generally as “circuitry,” a “circuit,” or “circuits” that is or are configured to implement at least some of the associated functionality. When implemented in software, such software can be implemented in software or firmware executing on one or more suitable programmable processors (or other programmable device) or configuring a programmable device (for example, processors or devices included in or used to implement special-purpose hardware, general-purpose hardware, and/or a virtual platform). In such a software example, the software can comprise program instructions that are stored (or otherwise embodied) on or in an appropriate non-transitory storage medium or media (such as flash or other nonvolatile memory, magnetic disc drives, and/or optical disc drives) from which at least a portion of the program instructions are read by the programmable processor or device for execution thereby (and/or for otherwise configuring such processor or device) in order for the processor or device to perform one or more functions described here as being implemented the software. Such hardware or software (or portions thereof) can be implemented in other ways (for example, in an application specific integrated circuit (ASIC), etc.). Such entities can be implemented in other ways.

[0041] The DAS 100 can be implemented in a virtualized manner or a non-virtualized manner. When implemented in a virtualized manner, one or more nodes, units, or functions of the DAS 100 are implemented using one or more virtual network functions (VNFs) executing on one or more physical server computers (also referred to here as “physical servers” or just “servers”) (for example, one or more commercial- off-the-shelf (COTS) servers of the type that are deployed in data centers or “clouds” maintained by enterprises, communication service providers, or cloud services providers). More specifically, in the exemplary embodiment shown in Figure 1, each O-RAN donor unit 122 is implemented as a VNF running on a server 126. The server 126 can execute other VNFs 128 that implement other functions for the DAS 100 (for example, fronthaul, management plane, and synchronization plane functions). The various VNFs executing on the server 126 are also referred to here as “master unit” functions 130 or, collectively, as the “master unit” 130. Also, in the exemplary embodiment shown in Figure 1, each ICN 112 is implemented as a VNF running on a server 132.

[0042] The RF donor units 114 and CPRI donor units 118 can be implemented as cards (for example, Peripheral Component Interconnect (PCI) Cards) that are inserted in the server 126. Alternatively, the RF donor units 114 and CPRI donor units 118 can be implemented as separate devices that are coupled to the server 126 via dedicated Ethernet links or via a switched Ethernet network (for example, the switched Ethernet network 134 described below).

[0043] In the exemplary embodiment shown in Figure 1, the donor units 104, RUs 106 and ICNs 112 are communicatively coupled to one another via a switched Ethernet network 134. Also, in the exemplary embodiment shown in Figure 1, an O- RAN DU 124 can be coupled to a corresponding O-RAN donor unit 122 via the same switched Ethernet network 134 used for communication within the DAS 100 (though each O-RAN DU 124 can be coupled to a corresponding O-RAN donor unit 122 in other ways). In the exemplary embodiment shown in Figure 1, the downlink and uplink transport data communicated between the units of the DAS 100 is formatted as O-RAN data that is communicated in Ethernet packets over the switched Ethernet network 134. In the exemplary embodiment shown in Figure 1, the RF donor units 114 and CPRI donor units 118 are coupled to the RUs 106 and ICNs 112 via the master unit 130.

[0044] In the downlink, the RF donor units 114 and CPRI donor units 118 provide downlink time-domain baseband IQ data to the master unit 130. The master unit 130 generates downlink O-RAN user-plane messages containing downlink baseband IQ that is either the time-domain baseband IQ data provided from the donor units 114 and 118 or is derived therefrom (for example, where the master unit 130 converts the received time-domain baseband IQ data into frequency-domain baseband IQ data). The master unit 130 also generates corresponding downlink O-RAN control-plane messages for those O-RAN user-plane messages. The resulting downlink O-RAN user-plane and control-plane messages are communicated (multicasted) to the RUs 106 in the simulcast zone of the corresponding base station 102 via the switched Ethernet network 134.

[0045] In the uplink, for each RF -interface base station 116 and CPRI BBU 120, the master unit 130 receives O-RAN uplink user-plane messages for the base station 116 or CPRI BBU 120 and performs a combining or summing process using the uplink baseband IQ data contained in those messages in order to produce combined uplink baseband IQ data, which is provided to the appropriate RF donor unit 114 or CPRI donor unit 118. The RF donor unit 114 or CPRI donor unit 118 uses the combined uplink baseband IQ data to generate a set of base station signals or CPRI data that is communicated to the corresponding RF-interface base station 116 or CPRI BBU 120. If time-domain baseband IQ data has been converted into frequency-domain baseband IQ data for transport over the DAS 100, the donor unit 114 or 118 also converts the combined uplink frequency-domain IQ data into combined uplink time-domain IQ data as part of generating the set of base station signals or CPRI data that is communicated to the corresponding RF-interface base station 116 or CPRI BBU 120.

[0046] In the exemplary embodiment shown in Figure 1, the master unit 130 (more specifically, the O-RAN donor unit 122) receives downlink O-RAN user-plane and control -plane messages from each served O-RAN DU 124 and communicates (multicasts) them to the RUs 106 in the simulcast zone of the corresponding O-RAN DU 124 via the switched Ethernet network 134. In the uplink, the master unit 130 (more specifically, the O-RAN donor unit 122) receives O-RAN uplink user-plane messages for each served O-RAN DU 124 and performs a combining or summing process using the uplink baseband IQ data contained in those messages in order to produce combined uplink IQ data. The O-RAN donor unit 122 produces O-RAN uplink user-plane messages containing the combined uplink baseband IQ data and communicates those messages to the O-RAN DU 124.

[0047] In the exemplary embodiment shown in Figure 1, only uplink transport data is communicated using the ICNs 112, and downlink transport data is communicated from the master unit 130 to the RUs 106 without being forwarded by, or otherwise communicated using, the ICNs 112. [0048] Figure 2 illustrates another exemplary embodiment of a DAS 100. The DAS 100 shown in FIG. 2 is the same as the DAS 100 shown in Figure 1 except as described below. In the exemplary embodiment shown in Figure 2, the RF donor units 114 and CPRI donor units 118 are coupled directly to the switched Ethernet network 134 and not via the master unit 130, as is the case in the embodiment shown in Figure 1.

[0049] As described above, in the exemplary embodiment shown in Figure 1, the master unit 130 performs some transport functions related to serving the RF -interface base stations 116 and CPRI BBUs 120 coupled to the donor units 114 and 118. In the exemplary embodiment shown in Figure 2, the RF donor units 114 and CPRI donor units 118 perform those transport functions (that is, the RF donor units 114 and CPRI donor units 118 perform all of the transport functions related to serving the RF- interface base stations 116 and CPRI BBUs 120, respectively).

[0050] Figure 3 illustrates another exemplary embodiment of a DAS 100. The DAS 100 shown in Figure 3 is the same as the DAS 100 shown in Figure 1 except as described below. In the exemplary embodiment shown in Figure 3, the donor units 104, RUs 106 and ICNs 112 are communicatively coupled to one another via point-to- point Ethernet links 136 (instead of a switched Ethernet network). Also, in the exemplary embodiment shown in Figure 3, an O-RAN DU 124 can be coupled to a corresponding O-RAN donor unit 122 via a switched Ethernet network (not shown in Figure 3), though that switched Ethernet network is not used for communication within the DAS 100. In the exemplary embodiment shown in Figure 3, the downlink and uplink transport data communicated between the units of the DAS 100 is communicated in Ethernet packets over the point-to-point Ethernet links 136.

[0051] For each southbound point-to-point Ethernet link 136 that couples a master unit 130 to an ICN 112, the master unit 130 assembles downlink transport frames and communicates them in downlink Ethernet packets to the ICN 112 over the point-to- point Ethernet link 136. For each point-to-point Ethernet link 136, each downlink transport frame multiplexes together downlink time-domain baseband IQ data and Ethernet data that needs to be communicated to southbound RUs 106 and ICNs 112 that are coupled to the master unit 130 via that point-to-point Ethernet link 136. The downlink time-domain baseband IQ data is sourced from one or more RF donor units 114 and/or CPRI donor units 118. The Ethernet data comprises downlink user-plane and control-plane O-RAN fronthaul data sourced from one or more O-RAN donor units 122 and/or management-plane data sourced from one or more management entities for the DAS 100. That is, this Ethernet data is encapsulated into downlink transport frames that are also used to communicate downlink time-domain baseband IQ data and this Ethernet data is also referred to here as “encapsulated” Ethernet data. The resulting downlink transport frames are communicated in the payload of downlink Ethernet packets communicated from the master unit 130 to the ICN 112 over the point-to-point Ethernet link 136. The Ethernet packets into which the encapsulated Ethernet data is encapsulated are also referred to here as “transport” Ethernet packets.

[0052] Each ICN 112 receives downlink transport Ethernet packets via each northbound point-to-point Ethernet link 136 and extracts any downlink time-domain baseband IQ data and/or encapsulated Ethernet data included in the downlink transport frames communicated via the received downlink transport Ethernet packets. Any encapsulated Ethernet data that is intended for the ICN 112 (for example, management-plane Ethernet data) is processed by the ICN 112.

[0053] For each southbound point-to-point Ethernet link 136 coupled to the ICN 112, the ICN 112 assembles downlink transport frames and communicates them in downlink Ethernet packets to the southbound entities subtended from the ICN 112 via the point-to-point Ethernet link 136. For each southbound point-to-point Ethernet link 136, each downlink transport frame multiplexes together downlink time-domain baseband IQ data and Ethernet data received at the ICN 112 that needs to be communicated to those subtended southbound entities. The resulting downlink transport frames are communicated in the payload of downlink transport Ethernet packets communicated from the ICN 112 to those subtended southbound entities ICN 112 over the point-to-point Ethernet link 136.

[0054] Each RU 106 receives downlink transport Ethernet packets via each northbound point-to-point Ethernet link 136 and extracts any downlink time-domain baseband IQ data and/or encapsulated Ethernet data included in the downlink transport frames communicated via the received downlink transport Ethernet packets. As described above, the RU 106 uses any downlink time-domain baseband IQ data and/or downlink O-RAN user-plane and control-plane fronthaul messages to generate downlink RF signals for radiation from the set of coverage antennas 108 associated with that RU 106. The RU 106 processes any management-plane messages communicated to that RU 106 via encapsulated Ethernet data.

[0055] Also, for any southbound point-to-point Ethernet link 136 coupled to the RU 106, the RU 106 assembles downlink transport frames and communicates them in downlink Ethernet packets to the southbound entities subtended from the RU 106 via the point-to-point Ethernet link 136. For each southbound point-to-point Ethernet link 136, each downlink transport frame multiplexes together downlink time-domain baseband IQ data and Ethernet data received at the RU 106 that needs to be communicated to those subtended southbound entities. The resulting downlink transport frames are communicated in the payload of downlink transport Ethernet packets communicated from the RU 106 to those subtended southbound entities ICN 112 over the point-to-point Ethernet link 136.

[0056] In the uplink, each RU 106 generates uplink time-domain baseband IQ data and/or uplink 0-RAN user-plane fronthaul messages for each RF-interface base station 116, CPRI BBU 120, and/or 0-RAN DU 124 served by that RU 106 as described above. For each northbound point-to-point Ethernet link 136 of the RU 106, the RU 106 assembles uplink transport frames and communicates them in uplink transport Ethernet packets northbound towards the appropriate master unit 130 via that point-to-point Ethernet link 136. For each northbound point-to-point Ethernet link 136, each uplink transport frame multiplexes together uplink time-domain baseband IQ data originating from that RU 106 and/or any southbound entity subtended from that RU 106 as well as any Ethernet data originating from that RU 106 and/or any southbound entity subtended from that RU 106. In connection with doing this, the RU 106 performs the combining or summing process described above for any base station 102 served by that RU 106 and also by one or more of the subtended entities. (The RU 106 forwards northbound all other uplink data received from those southbound entities.) The resulting uplink transport frames are communicated in the payload of uplink transport Ethernet packets northbound towards the master unit 130 via the associated point-to-point Ethernet link 136.

[0057] Each ICN 112 receives uplink transport Ethernet packets via each southbound point-to-point Ethernet link 136 and extracts any uplink time-domain baseband IQ data and/or encapsulated Ethernet data included in the uplink transport frames communicated via the received uplink transport Ethernet packets. For each northbound point-to-point Ethernet link 136 coupled to the ICN 112, the ICN 112 assembles uplink transport frames and communicates them in uplink transport Ethernet packets northbound towards the master unit 130 via that point-to-point Ethernet link 136. For each northbound point-to-point Ethernet link 136, each uplink transport frame multiplexes together uplink time-domain baseband IQ data and Ethernet data received at the ICN 112 that needs to be communicated northbound towards the master unit 130. The resulting uplink transport frames are communicated in the payload of uplink transport Ethernet packets communicated northbound towards the master unit 130 over the point-to-point Ethernet link 136.

[0058] Each master unit 130 receives uplink transport Ethernet packets via each southbound point-to-point Ethernet link 136 and extracts any uplink time-domain baseband IQ data and/or encapsulated Ethernet data included in the uplink transport frames communicated via the received uplink transport Ethernet packets. Any extracted uplink time-domain baseband IQ data, as well as any uplink 0-RAN messages communicated in encapsulated Ethernet, is used in producing a single “combined” set of uplink base station signals or data for the associated base station 102 as described above (which includes performing the combining or summing process). Any other encapsulated Ethernet data (for example, management-plane Ethernet data) is forwarded on towards the respective destination (for example, a management entity).

[0059] In the exemplary embodiment shown in Figure 3, synchronization-plane messages are communicated using native Ethernet packets (that is, non-encapsulated Ethernet packets) that are interleaved between the transport Ethernet packets.

[0060] Figure 4 illustrates another exemplary embodiment of a DAS 100. The DAS 100 shown in Figure 4 is the same as the DAS 100 shown in Figure 3 except as described below. In the exemplary embodiment shown in Figure 4, the CPRI donor units 118, 0-RAN donor unit 122, and master unit 130 are coupled to the RUs 106 and ICNs 112 via one or more RF units 114. That is, each RF unit 114 performs the transport frame multiplexing and demultiplexing that is described above in connection with Figure 3 as being performed by the master unit 130.

[0061] Figure 5 illustrates an exemplary embodiment of a system 500. The system 500 shown in Figure 5 includes a DAS 100 with similar components to the DAS 100 described above with respect to Figures 1-4. The functions, structures, and other description of common elements of the DAS 100 discussed above with respect to Figures 1-4 are also applicable to like named features in the DAS 100 shown in Figure 5. Further, the like named features included in Figures 1-4 are numbered similarly.

[0062] In the particular example shown in Figure 5, system 500 includes one or more central units (CUs) 512 and one or more distributed units (DUs) 124 communicatively coupled to the DAS 100. The CU 512 and DUs 124 form part of one or more baseband entities 510 (understanding that other baseband configurations, such as a 4G BBU, can be used as the baseband entity 510). The system is implemented in accordance with one or more public standards and specifications. In some examples, the system is implemented using the logical RAN nodes, functional splits, and fronthaul interfaces defined by the O-RAN Alliance. In the example shown in Figure 5, each CU 512 and DU 124 is implemented as an O-RAN central unit (O-CU) and an O-RAN distributed unit (O-DU) respectively, in accordance with the O-RAN specification. Although not shown, in some examples one or more RUs 106 are implemented as an O-RAN radio unit (O-RU). In other examples, one or more RUs are implemented as an O-RU and one or more RUs are implemented as a legacy RU. The RUs 106 that are part of the DAS 100 comprise examples of the DAS node(s) 524, which, as further described, can also include other nodes such as the master unit (MU) 130, ICNs 112, and intermediate switches.

[0063] In the example shown in Figure 5 the system 500 includes a single CU 512, which is split between one or more CU-CP 514 that handle control plane functions and one or more CU-UP 516 that handle user plane functions. The CU 512 comprises a logical node hosting Packet Data Convergence Protocol (PDCP), Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP), and other control functions. Therefore, each CU 512 implements the gNB controller functions such as the transfer of user data, mobility control, radio access network sharing, positioning, session management, etc. The CU(s) 512 control the operation of the DUs 124 over an interface (including Fl-C and Fl-U for the control plane and user plane, respectively). In the example shown in Figure 5, the CU 512 handles control plane functions, user plane functions, some non-real-time functions, and/or PDCP processing. The CU-CP 514 may communicate with at least one wireless service provider’s Next Generation Cores (NGC) using a 5GNG-C interface and the CU-UP 516 may communicate with at least one wireless service provider’s NGC using a 5GNG-U interface.

[0064] Each DU 124 comprises a logical node hosting (performing processing for) Radio Link Control (RLC) and Media Access Control (MAC) layers, as well as optionally the upper or higher portion of the Physical (PHY) layer (where the PHY layer is split between the DU and RU). In other words, the DUs 124 implement a subset of the gNB functions, depending on the functional split (between CU 512 and DU 124). In some configurations, the Layer-3 processing (of the 5G air interface) may be implemented in the CU 512 and the Layer-2 processing (of the 5G air interface) may be implemented in the DU 124. Two DUs 124 are illustrated in Figure 5 for pedagogical explanation, and any number of DUs 124 (including a single DU) may form part of the baseband entity 510.

[0065] Although the CU 512 (including the CU-CP 514 and CU-UP 516), DU 124, master unit 130, ICN 112, and RUs 106 are described as separate logical entities, one or more of them can be implemented together using shared physical hardware and/or software. For example, in the example shown in Figure 5, for each cell, the CU 512 (including the CU-CP 514 and CU-UP 516) and DU 124 serving that cell could be physically implemented together using shared hardware and/or software, whereas each RU 106 would be physically implemented using separate hardware and/or software. Alternatively, the CU(s) (including the CU-CP 514 and CU-UP 516) may be remotely located from the DU(s) 124.

[0066] The one or more baseband unit entities 510 (for example, CU-CP 514, CU-UP 516, DU 124) can be implemented using a scalable cloud environment in which resources used to instantiate each type of entity can be scaled horizontally (that is, by increasing or decreasing the number of physical computers or other physical devices) and vertically (that is, by increasing or decreasing the “power” (for example, by increasing the amount of processing and/or memory resources) of a given physical computer or other physical device). The scalable cloud environment can be implemented in various ways. For example, the scalable cloud environment can be implemented using hardware virtualization, operating system virtualization, and application virtualization (also referred to as containerization) as well as various combinations of two or more of the preceding. The scalable cloud environment can be implemented in other ways. For example, the scalable cloud environment is implemented in a distributed manner. That is, the scalable cloud environment is implemented as a distributed scalable cloud environment comprising at least one central cloud, at least one edge cloud, and at least one radio cloud.

[0067] In some examples, each DU 124 is implemented as a single virtualized entity executing on a single cloud worker node. In some examples, the at least one CU-CP 514 and the at least one CU-UP 516 can each be implemented as a single virtualized entity executing on the same cloud worker node or as a single virtualized entity executing on a different cloud worker node. However, it is to be understood that different configurations and examples can be implemented in other ways. For example, the CU 512 can be implemented using multiple CU-UP VNFs and using multiple virtualized entities executing on one or more cloud worker nodes. In another example, multiple DUs 124 (using multiple virtualized entities executing on one or more cloud worker nodes) can be used to serve a cell, where each of the multiple DUs 124 serves a different set of RUs 106. Moreover, it is to be understood that the CU 512 and DUs 124 can be implemented in the same cloud (for example, together in the radio cloud or in an edge cloud). Other configurations and examples can be implemented in other ways.

[0068] The DAS 100 is configured to be directly coupled (i.e. without intervening components of the RAN) to the service management, and orchestrator (SMO) entity 502. As described further herein, the SMO entity 502 is configured to determine one or more energy saving policies and send configuration parameters in accordance with the energy saving polic(ies) to the DAS 100 and/or baseband entit(ies) 510. In some examples, the SMO 502 is coupled to the DAS 100 via an 01 or 02 interface. In the example shown in Figure 5, the DAS 100 is directly coupled to an element management system (EMS) 104, and can be coupled to other components of the SMO 502 such as the non-real time RIC 506.

[0069] The system 500 further includes a non-real time RAN intelligent controller (RIC) 506 and a near-real time RIC 508. The non-real time RIC 506 and the near-real time RIC 508 are separate entities in the O-RAN architecture and serve different purposes. In some examples, the non-real time RIC 506 is implemented as a standalone application in a cloud network. In some examples, the near-real time RIC 508 is implemented as a standalone application in a cloud network. In other examples, the near-real time RIC 508 is embedded in the CU 512. The non-real time RIC 506 and/or the near-real time RIC 508 can also be deployed in other ways.

[0070] The non-real time RIC 506 is responsible for non-real time flows in the system (typically greater than or equal to 1 second) and configured to execute one or more machine learning models, which are also referred to as “rApps.” The near-real time RIC 508 is responsible for near-real time flows in the system (typically 10 ms to 1 second) and configured to execute one or more machine learning models, which are also referred to as “xApps.”

[0071] In some examples, the machine learning models can be trained, at least in part, offline and/or at a different location from where they are deployed (for example, at the non-real time RIC 506 or SMO 502 for xApps). In some examples, the machine learning models of the near-real time RIC 508 and the non-real time RIC 506 are trained online during operation where they are deployed (at the near-real time RIC 508 or non-real time RIC 506) in addition to, or instead of, the machine learning models being trained offline. The machine learning models can be trained using one or more techniques (for example, reinforcement learning, linear regression, logistic regression, deep neural network, or the like). It should be understood that other techniques can also be used, and the machine learning models can be trained and deployed in other ways such as, for example, any of the ways described in the 0-RAN Working Group (WG) 2 Artificial Intelligence (Al) Machine Learning (ML) Technical Report (0-RAN.WG2.AIML-v01.03) (referred to herein as the “0-RAN AIML Technical Report”), which is incorporated herein by reference.

[0072] In some examples, the non-real time RIC 506 is configured to provide machine learning models, policy guidance (for example, using a POLICY message as defined in the 0-RAN E2AP Specification), and/or enrichment information (for example, to train the machine learning model(s) deployed at the near-real time RIC 508) to the near-real time RIC 508. In some such examples, the non-real time RIC 506 is configured to provide the machine learning models, policy guidance, and/or enrichment information to the near-real time RIC 508 via an Al interface.

[0073] In some examples, the master unit 130 and the ICN 112 are configured to comply with the 0-RAN definition of an E2 node. In some examples, the master unit 130 and ICN 112 each include an E2 interface configured to communicate with the near-real time RIC 508 that is similar to the E2 interface as defined for the CU 512 or DU 124. For example, the master unit 130 and the ICN 112 include E2 interfaces that comply with the required features as defined in the 0-RAN Near-Real-time RAN Intelligent Controller, E2 Application Protocol (E2AP) v2.02 (referred to herein as the “0-RAN E2AP Specification”), which is incorporated herein by reference. The master unit 130 and ICN 112 can be communicatively coupled to the near-real time RIC 508 via a respective E2 interface. The near-real time RIC 508 can be directly coupled to the master unit 130 and ICN 112. It should be understood that other configurations could also be implemented. For example, the near-real time RIC 508 can also be indirectly coupled to one or more components of the DAS 100 via another component of the DAS 100 (e.g., by DAS management controller 522).

[0074] In some examples, the master unit 130 and ICN 112 also include an O1/O2 interface configured to communicate with the non-real time RIC 506. The master unit 130 and ICN 112 can be communicatively coupled to the non-real time RIC 506 via the respective O1/O2 interface. It should be understood that other configurations could also be implemented. For example, the non-real time RIC 506 can also be indirectly coupled to one or more components of the DAS 100 via another component of the DAS 100 (e.g., by DAS management controller 522).

[0075] In the example shown in Figure 5, DAS management controller 522 is configured to comply with the 0-RAN definition of an E2 node. In some examples, DAS management controller 522 includes an E2 interface configured to communicate with the near-real time RIC 508 that is similar to the E2 interface as defined for the CU 512 or DU 124 in the 0-RAN E2AP Specification. While in system 500, the near- real time RIC 508 is directly coupled to DAS management controller 522, other configurations could also be implemented. For example, the near-real time RIC 508 can also be indirectly coupled to DAS management controller 522 via another component of the DAS 100.

[0076] During operation, the DAS 100 (including the master unit 130 and ICNs 112) and the baseband entity 510 are configured to provide fronthaul information (for example, using a REPORT message as defined in the 0-RAN E2AP Specification) to the near-real time RIC 508 via the E2 interface. In some examples, the fronthaul information provided to the near-real time RIC 508 is fronthaul information retrieved from an eCPRI interface at different levels within the DAS. The fronthaul information can include an indication regarding whether IQ data packets are compressed or uncompressed, information from eCPRI headers (for example, stream information, channel information, etc.), eCPRI control/signal message packets (for example, delay or latency measurements, buffer status, transmit power via Real Time Control Data (RTCD)), transport network performance measure (jitter, block error rate (BER), etc.), a number of RUs connected in the downlink, a number of RUs connected in the uplink (for example, for the UE based on the noise floor set), link capacity (for example, including total capacity and the headroom for inbound and outbound at the node), topology information for the cell (for example, hierarchy information, location information, etc. that can be used to estimate the end-to-end number of hops, delay beyond the node, and/or correlate delays from multiple nodes and account for the topology). It should be understood that other fronthaul information could also be sent from the DAS 100 and baseband entity 510.

[0077] In some examples, the DAS 100 and baseband entity 510 are configured to periodically provide the fronthaul information to the near-real time RIC 508. For example, DAS 100 and baseband entity 510 can be configured to provide the fronthaul information at regular time intervals to the near-real time RIC 508. In some examples, DAS 100 and baseband entity 510 are configured to provide the fronthaul information to the near-real time RIC 508 based on an event. For example, the event may include receiving a request for the fronthaul information from the near-real time RIC 508, a change in network conditions, etc. It should be understood that the DAS 100 and baseband entity 510 can provide fronthaul information periodically and based on an event, and the particular time intervals and events are configurable depending on the desired performance of the system.

[0078] The near-real time RIC 508 is configured to receive the fronthaul information provided by the DAS 100 and baseband entity 510 via the E2 interface(s). The near- real time RIC 508 is configured to process the fronthaul information provided via the E2 interface(s) and provide the processed fronthaul information to non-real time RIC 506 (e.g., via an Al interface). In some examples, the near-real time RIC 508 uses one or more machine learning models to process the fronthaul information within tolerable time constraints. In some examples, the near-real time RIC 508 is configured to use policy guidance provided by the non-real time RIC 506 in addition to, or instead of, processing the fronthaul information for the components of the system 500. [0079] During initial startup and during continuous operation, each component of baseband entity 510 and each node 524 of the DAS will determine various operational parameters that represent the performance of a given component/node and will determine respective activity parameters. The operational parameters represent the performance of a given component/node of the DAS, for example, performance counters that can be embodied as key performance indicators (KPIs). The activity parameters represent the activity of a given component/node of the DAS during a time interval of DAS operation (such as activity logs reported in the M-plane), and may also be represented as KPIs. For example, an RU 106 may determine and record operational parameters such as the number of radio resource control (RRC) connected users in the cell that the given RU is providing wireless coverage, the number of high priority and emergency users in the cell, the downlink traffic data volume in the cell, and the uplink traffic data volume in the cell. Other operational parameters can be reported (such as the fronthaul information provided by the E2 interface). When implemented, DAS management controller 522 is configured to determine the operational parameters and/or activity parameters of each DAS node 524. Additionally, or alternatively, MU 130 is configured to determine the operational parameters and/or activity parameters of each DAS node 524.

[0080] In addition to the E2 interface(s) that couple the DAS 100 to the near-real time RIC 508, the DAS 100 (and baseband entity 510) is also coupled to non-real time RIC 506. Non-real time RIC 506 is generally configured to determine one or more energy saving policy configurations based on information acquired from the DAS 100. In some examples, SMO 502 is configured to trigger periodic transmission of operational parameters and activity logs by the baseband entity 510 and DAS management controller 522, for example, to update an energy saving policy configuration or to implement a new energy saving policy configuration.

[0081] In the example of Figure 5, non-real time RIC 506 is configured to receive the operational parameters and/or activity parameters of the DAS nodes 524, as well as the operational parameters and/or activity parameters of the baseband entity 510. Based on the operational parameters and activity parameters, non-real time RIC 506 is configured to determine configuration parameters for each of the CU 512, DUs 124, and DAS nodes 524. The configuration parameters for a given component/node represent how the given component/node will function during operation for a period of time. For example, non-real time RIC 506 may determine configuration parameters that indicate that an RU will be rendered inactive, or that one or more ports of the RU that correspond to a carrier will be turned off. In some examples, configuration parameters are determined based on one or more energy saving policies to reduce energy consumption in the DAS 100 or the system 500 more generally. DAS 100 provides the operational parameters and activity parameters to the non-real time RIC 506 via one or more interfaces that directly couple the DAS 100 to the non-real time RIC 506.

[0082] Non-real time RIC 506 provides the configuration parameters for each component/node to EMS 504. EMS 504 is configured to distribute the respective configuration parameters for each component to the DAS 100 and optionally the baseband entity 510. EMS 504 (and the SMO 502 more generally) is configured to adjust operation of one or more components of the system 500 based on the one or more configuration parameters for the DAS nodes 524 and optionally for the baseband entity 510. The EMS 504 is configured to adjust operation of one or more components of the system 500 to improve capacity, coverage, and performance of the system. In some examples, adjusting operation of one or more components of the system 500 includes a determination of particular actions to take and providing control signals to the one or more components of the system 500 to implement the determined actions. It should be understood that the adjustment of operation for one or more components of the DAS 100 can affect downlink operation, uplink operation, or both downlink operation and uplink operation.

[0083] In some examples, the EMS 504 is configured to adjust operation of one or more components of the system 500 by activating or deactivating modulation schemes (for example, used between the DU 124 and the RUs 106). In some examples, the EMS 504 is configured to activate or deactivate modulation schemes for a select functional split or for specific donors. In some examples, the EMS 504 communicates with the DU 124 and the RUs 106 to implement the activation or deactivation of modulation schemes.

[0084] In some examples, the EMS 504 is configured to adjust operation of one or more components of the system 500 by adjusting a number of layers (for example, multiple-input multiple-output layers), flows, or streams supported by the DAS 100. In some examples, the EMS 504 communicates with the DU 124 to implement adjustment of the number of layers, flows, or streams supported by the DAS 100.

[0085] In some examples, the EMS 504 is configured to adjust operation of one or more components of the system 500 by adjusting the transmit power and/or buffer sizes for one or more components of the DAS 100. In some examples, the EMS 504 communicates with the master unit 130 and ICN 112 directly to implement adjustment of the number of layers, flows, or streams supported by the DAS 100.

[0086] In some examples, the EMS 504 is configured to adjust operation of one or more components of the system 500 by enabling or disabling functionality performed by one or more components of the DAS 100. For example, the EMS 504 can enable or disable functionality including, but not limited to, concatenation and IQ compression. In some examples, the EMS 504 communicates with the master unit 130 and ICN 112 directly to implement enabling or disabling functionality.

[0087] In some examples, the EMS 504 is configured to adjust operation of one or more components of the system 500 by modifying the dimensioning of the transport network. For example, the EMS 504 can adjust the throughput capacities, ports, speed of the ports, Differentiated Services Code Point (DSCP) marking, virtual local area network (VLAN) tagging, and the like. In some examples, the EMS 504 communicates with the master unit 130, ICN 112, and/or switches 202, 204 to implement dimensioning of the transport network.

[0088] In some examples, the EMS 504 is configured to adjust operation of one or more components of the system 500 by adjusting the power consumption of the DAS 100. In some such examples, the EMS 504 can activate/deactivate streams and/or DAS nodes 524 depending on activity level indicated by the activity parameters. For example, if one or more RUs 106 are not being utilized (for example, the one or more RUs are not being combined in the uplink), then the streams to/from the one or more RUs and/or the RUs themselves can be disabled or deactivated. Particular examples of energy saving policies for the DAS 100 are discussed further below with respect to Figures 7-9.

[0089] In some examples, the EMS 504 provides control signals to the one or more components of the system 500 that includes the DAS 100 to adjust operation of the one or more components of the DAS 100. For example, the EMS 504 can provide the control signals to the one or more components of the system 500 via an E2 interface. In some examples, the EMS 504 only transmits control signals to master unit 130 and ICNs 112 when a change is needed. In some examples, the EMS 504 transmits the control signals only to the components of the DAS 100 that require changes for the particular time period. In other examples, the EMS 504 broadcasts the updates to all of the components in the DAS 100, but only those components requiring change process the updates.

[0090] As previously noted, EMS 504 is coupled directly to DAS 100 through one or more interfaces (e.g., O1/O2 interfaces). In some examples, EMS 504 is coupled to DAS management controller 522, and is configured to send configuration parameters to the DAS management controller 522. In other examples, EMS 504 is coupled to one or more of the DAS nodes 524, such as master unit 130, ICNs 112, and RUs 106. When EMS 504 determines configuration parameters pursuant to an energy saving policy, EMS 504 is configured to configure DAS 100 according to the energy saving policy through the one or more interfaces. EMS 504 can also send configuration parameters and control information for baseband entity 510 and its associated components.

[0091] Figure 6 depicts another example of a DAS 100 as described in Figures 1-5, which although not shown in Figure 6, is coupled to one or more baseband entities 510 and SMO 502. In the example shown in Figure 6, the master unit 130 is communicatively coupled to the RUs 106A via an access (ACC) switch 204A, and is coupled to the RUs 106B via an aggregation (AGG) switch 202 and an access switch 204B communicatively coupled to the aggregation switch 202. In the exemplary embodiment shown in Figure 6, uplink transport data can be communicated using the optional ICNs 112 or radio units 106A, and downlink transport data can be communicated from the master unit 130 to the RUs 106A-B without being forwarded by, or otherwise communicated using, the ICNs 112. It should be understood that other configurations could also be used where the ICNs 112 forward downlink transport data to the group of southbound RUs 106B.

[0092] The aggregation switch 202 and the access switches 204A-B can be implemented as physical switches or virtual switches running in a cloud (for example, a radio cloud). In some examples, the aggregation switch 202 and the access switches 204A-B are SDN capable and enabled switches. In some such examples, the aggregation switch 202 and the access switches 204A-B are OpenFlow capable and enabled switches. In such examples, the aggregation switch 202 and the access switches 204 A-B are configured to distribute the downlink fronthaul data packets according to forwarding rules in respective flow tables and corresponding flow entries for each respective flow table.

[0093] For downlink fronthaul traffic, the aggregation switch 202 is configured to receive downlink fronthaul data packets from the master unit 130 and distribute the downlink fronthaul data packets to the RUs 106B via the access switch 204B. In some examples, the aggregation switch 202 receives a single copy of each downlink fronthaul data packet from the master unit 130 for each UE 110. In some examples, each copy is segmented into IP packets that have a destination address that is set to the address of the multicast group associated with that copy. The downlink fronthaul data packet is replicated and transmitted by the aggregation switch 202 and access switch 204B as needed to distribute the downlink fronthaul data packets to the RUs 106B for the particular respective UEs 110.

[0094] In some examples, DAS 100 further includes a DAS management controller 522 configured to control the aggregation switch 202 and the access switches 204A- B. The DAS management controller 522 includes at least one communication interface 620 configured to send and receive information from the DAS nodes 524 and the SMO 502. In some examples, the DAS management controller 522 includes one or more processors 610, and the aggregation switch 202 and the access switch 204 are configured by the processors 610. In such examples, DAS management controller 522 can be configured to provide updates to the forwarding rules for the aggregation switch 202 and/or the access switches 204A-B via the out-of-band control messaging. Processor 610 may also include, or function with, software programs, firmware, or other computer readable instructions for carrying out various process tasks, calculations, and control functions, used in the methods herein. These instructions are typically tangibly embodied on any storage media (or computer readable media) used for storage of computer readable instructions or data structures. Memory 612 can include any available storage media (or computer readable medium) that can be accessed by a general purpose or special purpose computer or processor, or any programmable logic device. Suitable computer readable media may include storage or memory media such as semiconductor, magnetic, and/or optical media, and may be embodied as storing instructions in non-transitory computer readable media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM, electrically-erasable programmable ROM, flash memory, or other storage media.

[0095] In some examples, memory 612 stores a DAS configuration function 614 that, when executed by processor 610, causes processor 610 to configure one or more of MU 130, ICNs 112, AGG switch 202, ACC switches 204A-204B, or RUs 106 based on the configuration parameters received by SMO 502. When DAS management controller 522 is implemented, processor 610 receives the operating parameters and/or activity parameters of each of the MU 130, ICNs 112, and RUs 106 and may store the operational parameters and/or activity parameters in memory 612. Upon receiving the configuration parameters based on the operational parameters and/or activity parameters, DAS management controller 522 configures one or more of the MU 130, ICNs 112, AGG switch 202, ACC switches 204A-204B, or RUs 106 in accordance with the configuration parameters for each node. For example, if SMO 502 determines that there are an insufficient number of user equipment (UE) 110 utilizing a cell serviced by DAS 100, then DAS management controller 522 adjusts the operation of RUs 106 according to the new configuration so that some of the RUs become set in an inactive state. Exemplary energy saving configuration policies are described with respect to Figures 7-9. In this way, DAS management controller 522 can directly manage and implement the energy-saving configuration policies determined from SMO 502. Alternatively, the functionality of the DAS management controller 522 (including the energy policy configuration functionality) is integrated in the master unit 130. Thus, the DAS management controller 522 described in Figures 5-6 is exemplary and optional.

[0096] While Figures 5-6 shows a single CU-CP 514, a single CU-UP 516, two DUs 124, a single master unit 130, a single aggregation switch 202, a single ICNs 112, a two access switches 204A-B, and two RUs 106A-B, it should be understood that this is an example and other numbers of CU-CPs 514, CU-UPs 516, DUs 124, master units 130, aggregation switches 202 (including zero), ICNs 112, access switches 204 (including one), and/or RUs 106 can also be used.

[0097] DAS 100 is configured to implement one or more energy saving policies defined by the configuration parameters received from SMO 502. Energy saving policies are implemented in the DAS to reduce the energy consumption of DAS operation (that is, to reduce the energy costs of extending wireless coverage) when conditions such as low signal traffic allow for such policies to be implemented. For example, one of the cells serviced by DAS 100 may have a low density of UE 110 utilizing wireless coverage in the cell during a time interval in which the DAS is providing wireless service, as determined from a low volume of signal traffic for RUs 106 serving the cell. Additionally, or alternatively, one of the carriers providing wireless coverage in the cell may have a low volume of UEs 110 utilizing that particular carrier in the cell. In response to receiving the configuration parameters from SMO 502, DAS 100 (e.g., DAS management controller 522) configures MU 130, ICNs 112, and/or RUs 106 to reduce power consumption for nodes that are experiencing low signal traffic. In each of these examples, the DAS nodes 524 can be configured by MU 130 instead of DAS management controller 522.

[0098] In one example, the DAS management controller 522 is configured to set MU 130, ICNs 112, and/or RUs 106 in an inactive state based on the configuration parameters from SMO 502. For example, if RU 106 reports low signal traffic or low activity, DAS management controller 522 can set RU 106 to an inactive state in which downlink and uplink processing functions are disabled for RU 106. Only basic M- plane functions will remain active in the RU 106 so that it can continue to receive M- plane data from a management entity and report operational parameters and activity parameters. Alternatively, DAS management controller 522 can set one or more DAS nodes 524 (e.g., ICNs 112) in an inactive state for one or more carriers utilizing the DAS 100. In each of these examples, the DAS nodes 524 can be configured by MU 130 instead of DAS management controller 522.

[0099] In another example, DAS management controller 522 can facilitate transfer of user equipment associated with one cell to be shut down to a neighboring active cell by adjusting the electrical downtilt of one or more RUs associated with the neighboring cell. As an example, assume that SMO 502 implements an energy saving policy to shut down a cell due to lack of cellular traffic. In some examples, the DAS 100 is configured to stop servicing the cell, for example, by setting the RUs 106, or associated radio modules of RUs 106 serving the cell to an inactive state based on the configuration parameters received from SMO 502. In some examples, however, DAS management controller 522 can reconfigure the electrical beamtilt of RUs of a neighboring cell before rendering the cell inactive. Accordingly, DAS management controller 522 can send control signals to one or more RUs 106 in the neighboring cells and configure the RUs to adjust their electrical beamtilt so that the signal strength from these RUs will appear stronger to user equipment currently served by the soon-to-be inactive cell. Doing so facilitates easier handover for the user equipment to the neighboring cells since the increased signal strength as measured from the user equipment will make these cells more suitable for serving the user equipment previously associated with the inactive cell. In each of these examples, the DAS nodes 524 can be configured by MU 130 instead of DAS management controller 522.

[0100] Figure 7 is a message flow diagram illustrating communication between components of the systems in Figures 1-6. Each different entity is represented as a vertical line in the diagram, with the different entities shown as eNB and gNB (part of baseband entity 510), CU-UP 516, CU-CP 514, DU 124 DAS 100, RU 106, EMS 504 (part of SMO 502), and Access and Mobility Management Function (AMF). The DAS 100 functionality can be performed by a DAS management controller 522 and/or by one or more MUs 130 of the DAS 100. Unless otherwise specified, messages that are shown in Figure 7 and the following message flow diagrams as being higher relative to other messages are messages that are transmitted before a lower message.

Messages are shown as solid or dotted lines, and messages that are transmitted to a particular entity are shown in Figure 7 as an arrow to that entity. Messages that pass through a particular entity in Figure 7 are not necessarily indicative of a message being transmitted to that entity.

[0101] The message sequence begins with multiple entities of the RAN and DAS providing their respective operational parameters and/or activity parameters to non- RT RIC 506. More specifically, CU-CP 514 sends a message 702 reporting its operational parameters and/or activity parameters, followed by CU-UP 516 sending a message 704, and DU 124 sending a message 706, each reporting its operational parameters and/or activity parameters. Along with these entities, DAS 100 sends a message 708 reporting the operational parameters and activity parameters of the DAS nodes 524 managed by the DAS management controller 522. In doing so, non-RT RIC 506 gathers parameters from not only the RAN entities comprising the baseband entity 510, but also parameters from the DAS nodes 524 of DAS 100 that are deployed to extend the coverage of the RAN.

[0102] After receiving the operating parameters and/or activity parameters for each entity, non-RT RIC 506 processes the information and sends a message 710 with the processed data to EMS 504. EMS 504 is configured to determine one or more configuration parameters for the baseband RAN entities (CU-UP 516, CU-CP 514, DU 124) and for the DAS 100 based on the operational parameters and activity logs. The configuration parameters can be determined in accordance with an energy saving policy to reduce power consumption in the RAN and/or in the DAS. Such energy saving policy may include mechanisms such as reducing transmit power of one or more entities, setting one or more entities to an inactive state, shutting down one or more cells associated with the baseband RAN entities 510 and DAS 100, adjusting activity and performance parameters, updating automatic neighbor relation (ANR) lists for cells, and other mechanisms that result in reduced power consumption.

[0103] Next, EMS 504 distributes the configuration parameters to the baseband entities 510 and the DAS 100. More specifically, as shown in Figure 7, EMS 504 sends a message 710 to CU-CP 514 with the configuration parameters for baseband entity 510; in response, CU-CP 514 sends a reply message 714 to EMS 504 acknowledging the configuration parameters. CU-CP 514 then sends a message 716 to DU 124 configuring the DU 124 according to the configuration parameters. DU 124 responds by sending an acknowledgement message 718 to CU-CP 514. CU-CP 514 can configure DU 124 in various ways. In one embodiment, CU-CP 514 sends a message 720 to DU 124 that configures the DU to release the user equipment served by one or more cells set to an energy saving state. In one embodiment, CU-CP 514 configures DU 124 to prevent new user equipment utilizing the RAN from being served by one or more cells that will be set to an inactive state. For any user equipment that are currently being served by a cell that will be made inactive, CU-CP 514 can initiate a blind handover procedure to handover the user equipment to another active neighbor cell. Alternatively, CU-CP 514 can configure DU 124 to trigger a measurement event for the user equipment to report the signal strength of neighboring cells as possible target cells for handover based on the signal strength.

[0104] Once EMS 504 sends the message 712 with the configuration parameters for the baseband entity, EMS 504 sends a message 722 to DAS 100 with the configuration parameters for the DAS. In some examples, the messages 712 and 722 can be sent to both CU-CP 514 and DAS management controller 522 simultaneously. In response, DAS 100 sends a message 724 configuring one or more RUs 106 based on the received configuration parameters. For example, the configuration parameters may indicate that a cell serviced by the DAS 100 should be rendered inactive, in which case DAS 100 responds by sending a configuration message 724 that configures the RU 106 in the cell to an inactive state.

[0105] Figure 8 is a message flow diagram illustrating an exemplary energy saving policy for setting a carrier inactive. Figure 8 can be implemented with the systems described in Figures 1-6. Initially, non-RT RIC 506 sends a message 802 to EMS 504 indicating that a carrier that is currently being serviced by the RAN and DAS 100 will be deactivated. EMS 504 responds with a reply message 804 acknowledging the carrier deactivation to non-RT RIC 506. EMS 504 then sends a network configuration protocol (NETCONF) message 806 with the configuration parameters that enable the selected carrier to be rendered inactive to DU 124, and the DU responds with an acknowledgment message 808 back to EMS 504. DU 124 forwards the NETCONF message 810 to DAS 100 with the configuration parameters that enable the selected carrier to be rendered inactive as implemented on the DAS 100 end. For example, the message 810 can include information such as which RUs should be configured to stop servicing user traffic for the cell to be set inactive and the appropriate configuration state of the RUs to implement the deactivation of the carrier. DAS 100 then sends a NETCONF message 812 to the RUs 106 that configure the RUs 106 based on the configuration parameters, namely, to stop servicing the cell(s) selected for deactivation by EMS 504. Sequentially, or in parallel, RU 106 sends an acknowledgment message 814 back to DAS 100. DAS 100 also sends an acknowledgment message 816 back to DU 124.

[0106] In response to receiving confirmation from DAS 100 to deactivate the selected carrier, DU 124 sends a configuration update message 818 to CU-CP 514. CU-CP 514 also sends a message 820 to CU-UP 516 initializing a partial reset of the base station functionality in response to the deactivation of the selected carrier. CU-CP 514 also sends reset messages 822, 824, 826, and 828 to the AMF, DU 124, gNB, and eNB, respectively, thereby triggering a partial reset of each of these components. During partial reset, each component releases the allocated resources that are designated for user equipment associated with the deactivated carrier. CU-UP 516 sends an acknowledgement message 830 to CU-CP 514 for the Partial Reset message. In this example, the DU 124, AMF, gNB, and eNB each send an acknowledgment message 832, 834, 836, 838, respectively, back to CU-CP 514. CU-CP 514 then sends a configuration update message 840 and a configuration update message 842 to the gNB and eNB respectively, to configure the cells currently being served by the gNB and eNB to delete the reference to the inactive cell. Both gNB and eNB respond with an acknowledgment message 844, 846 to the CU-CP 514.

[0107] Figure 9 is a message flow diagram illustrating an exemplary energy saving policy for adjusting operation of radio units in a DAS 100. Figure 9 can be implemented with the systems described in Figures 1-6. Initially, non-real time RIC 506 sends a message 902 to EMS 504 to set one or more RUs 106 of the DAS 100 to a low-power mode or inactive (a “sleep” mode). EMS 504 sends a NETCONF message 904 to DAS 100 to configure the selected RUs to an inactive mode. As previously described, an RU in a low-power or inactive mode will not undergo control-plane and/or user-plane processing and transmission in the downlink and uplink directions, but may still retain some M-plane functionality such as the reporting of operational parameters and activity. DAS 100 responds by sending a configuration message 906 that configures the selected RUs to be in an inactive mode. RU 106 then sends an acknowledgement message 908 and enters an inactive mode. DAS 100 sends an acknowledgement message 910 to the EMS 504.

[0108] DAS 100 informs the baseband entity 510 of the change in operation of the selected RUs 106 by sending a message 912 to DU 124. DU 124 sends an acknowledgement message 914 back to DAS 100, followed by a message 916 to CU- CP 514 that triggers a partial reset of the other components of the RAN, as previously described in the context of Figure 8. That is, CU-CP 514 sends reset messages 918, 920, 922, 924, and 926 to the CU-UP 516, AMF, DU 124, gNB, and eNB, respectively, and receives acknowledgement messages 928, 930, 932, 934, and 936 from the CU-UP 516, AMF, DU 124, gNB, and eNB, respectively. CU-CP 514 then sends a configuration update message 938 and a configuration update message 940 to the gNB and eNB respectively, to configure the cells currently being served by the gNB and eNB based on the updated RU configuration. Both gNB and eNB respond with an acknowledgment message 942, 944 to the CU-CP 514. [0109] Figure 10 depicts a flow diagram of an exemplary method 1000 for configuring nodes of a DAS based on at least one energy saving policy. The blocks of the flow diagram have been arranged in a generally sequential manner for ease of explanation; however, it is to be understood that this arrangement is merely exemplary, and it should be recognized that the processing associated with the methods described herein (and the blocks shown in the Figures) may occur in a different order (for example, where at least some of the processing associated with the blocks is performed in parallel and/or in an event-driven manner). Also, most standard exception handling is not described for ease of explanation; however, it is to be understood that method 1000 can and typically would include such exception handling. Method 1000 can be performed by any of the DAS 100 described herein. In one example, method 1000 is performed by a DAS management controller 522. In another example, method 1000 is performed by one or more master units 130. Other active nodes of the DAS 100 can be configured to perform one or more blocks illustrated in Figure 10.

[0110] Method 1000 includes determining one or more operational parameters and/or one or more activity parameters for a plurality of nodes of a DAS at block 1002. The operational parameters represent the performance of a given component/node of the DAS, for example, performance counters that can be embodied as key performance indicators (KPIs). The activity parameters represent the activity of a given component/node of the DAS during a time interval of DAS operation (such as activity logs reported in the M-plane), and may also be represented as KPIs. The plurality of nodes of the DAS can include one or more master units, one or more ICNs, one or more radio units, one or more aggregation switches, one or more access switches, one or more controllers, and other components of the DAS. In some examples, the DAS is implemented as a virtual DAS. Optionally, one or more operational parameters and one or more activity parameters for baseband entity 510 or its associated components can also be determined in conjunction with the DAS nodes 524.

[OHl] Method 1000 proceeds to block 1004 and provides the operational and/or activity parameters to a service management and orchestrator entity (i.e. SMO 502). The parameters are provided via one or more interfaces that directly couple the DAS to the SMO, such as an 01 or 02 interface. In some examples, the parameters are provided to an EMS that is part of the SMO. [0112] At block 1006, method 1000 receives configuration param eter(s) for the plurality of nodes in the DAS. The configuration parameters are determined by the SMO based on the operational parameters and/or the activity parameters of the nodes of the DAS (optionally in conjunction with other components of the RAN, such as the baseband entity). The configuration parameters are also provided on the interface(s) that directly couples the DAS to the SMO. In some examples, the configuration parameters are determined in accordance with at least one energy saving policy determined by the SMO. Other components of the RAN, such as the baseband entity, may receive configuration parameters from the SMO using other interfaces, such as an El or E2 interface that couples the baseband entities, or its associated components, with the SMO.

[0113] Method 1000 then proceeds to block 1008 and configures the plurality of DAS nodes based on the configuration parameters. In some examples, the DAS includes a management controller that is configured to control the MU(s), ICN(s), and/or RUs of the DAS according to the configuration parameters determined by the SMO. In other examples, one or more master units are configured to control the ICN(s) and/or RUs according to the configuration parameters determined by the SMO. Other active nodes can be configured to configure other nodes of the DAS. In some examples, the EMS 504 can send control signals to the DAS 100.

[0114] By configuring the plurality of nodes based on the configuration parameters, the DAS experiences a reduction in power consumption for at least one node. In some examples, the DAS is configured to set at least one of the plurality of radio units in a low-power mode, so that while in the low-power mode, the at least one radio unit does not radiate (and receive) RF signals to user equipment or perform other userplane functions. In some examples, the DAS is configured to adjust the electrical beamtilt of at least one of the plurality of radio units in order to facilitate handover of user equipment to another cell. In some examples, the DAS is configured to render one or more cells serviced by the DAS inactive (e.g., by setting each radio unit associated with the cell to a low-power or inactive state when there are no user equipment associated with the cell). The DAS may configure the nodes in other ways.

[0115] The methods and techniques described herein may be implemented in digital electronic circuitry, or with a programmable processor (for example, a specialpurpose processor or a general-purpose processor such as a computer) firmware, software, or in various combinations of each. Apparatus embodying these techniques may include appropriate input and output devices, a programmable processor, and a storage medium tangibly embodying program instructions for execution by the programmable processor. A process embodying these techniques may be performed by a programmable processor executing a program of instructions to perform desired functions by operating on input data and generating appropriate output. The techniques may advantageously be implemented in one or more programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instruction to, a data storage system, at least one input device, and at least one output device. Generally, a processor will receive instructions and data from a read-only memory and/or a random-access memory. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile memory, including by way of example semiconductor memory devices, such as erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), and flash memory devices; magnetic disks such as internal hard disks and removable disks; magneto-optical disks; and the like. Any of the foregoing may be supplemented by, or incorporated in, specially-designed application specific integrated circuits (ASICs).

EXAMPLE EMBODIMENTS

[0116] Example 1 includes a method for reducing energy consumption in a distributed antenna system (DAS), wherein the DAS includes at least one master unit communicatively coupled to a plurality of radio units, wherein the at least one master unit is configured to receive downlink signals from at least one base station entity and to generate downlink transport signals from the downlink signals, wherein the plurality of radio units is configured to radiate radio frequency (RF) signals based on the downlink transport signals to user equipment, the method comprising: providing, from at least one interface that directly couples the DAS to a service, management, and orchestrator (SMO) entity, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS, wherein the one or more nodes of the DAS includes at least one of: the at least one master unit or at least one of the plurality of radio units; receiving, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the at least one operational parameter and/or the at least one activity parameter of the one or more nodes, wherein the at least one configuration parameter represents a change in operation configuration for the one or more nodes; and configuring the one or more nodes based on the at least one configuration parameter.

[0117] Example 2 includes the method of Example 1, wherein the at least one configuration parameter is based on at least one energy savings policy determined by the SMO entity, wherein the at least one energy savings policy, wherein by implementing the at least one energy savings policy, the DAS is configures a reduction in power consumption for the at least one radio unit.

[0118] Example 3 includes the method of any of Examples 1-2, wherein configuring the one or more nodes based on the at least one configuration parameter comprises setting at least one of the plurality of radio units in a low-power mode, wherein while in the low-power mode, the at least one radio unit does not radiate RF signals.

[0119] Example 4 includes the method of any of Examples 1-3, wherein configuring the one or more nodes based on the at least one configuration parameter comprises adjusting an electrical beamtilt of at least one of the plurality of radio units.

[0120] Example 5 includes the method of any of Examples 1-4, wherein configuring the one or more nodes based on the at least one configuration parameter comprises each radio unit associated with a cell to an inactive mode, thereby rendering the cell inactive.

[0121] Example 6 includes the method of any of Examples 1-5, wherein configuring the one or more nodes based on the at least one configuration parameter comprises configuring the one or more nodes via at least one of a DAS management controller communicatively coupled to the one or more nodes, the at least one master unit, or the SMO entity.

[0122] Example 7 includes the method of any of Examples 1-6, wherein the at least one interface that directly couples the DAS to the SMO entity include an 01 or 02 interface.

[0123] Example 8 includes the method of any of Examples 1-7, wherein the at least one operational parameter and/or the at least one activity parameter is reported in a management plane by each of the plurality of radio units. [0124] Example 9 includes a system, comprising: a distributed antenna system (DAS) directly coupled to a service, management, and orchestration (SMO) entity via one or more interfaces, the DAS comprising: at least one master unit, wherein the at least one master unit is configured to receive downlink signals from at least one base station entity and to generate downlink transport signals from the downlink signals; a plurality of radio units communicatively coupled to the at least one master unit, wherein the plurality of radio units is configured to radiate radio frequency (RF) signals based on the downlink transport signals to user equipment; wherein the DAS is configured to: provide, from the at least one interface, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS, wherein the one or more nodes of the DAS includes at least one of: the at least one master unit or at least one of the plurality of radio units; receive, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the at least one operational parameter and/or the at least one activity parameter of the one or more nodes, wherein the at least one configuration parameter represents a change in operation configuration for the one or more nodes; and configure the one or more nodes based on the at least one configuration parameter.

[0125] Example 10 includes the system of Example 9, further comprising a DAS management controller communicatively coupled to the one or more nodes, wherein the DAS management controller is configured to receive the at least one configuration parameter from the SMO entity, and to configure the one or more nodes based on the at least one configuration parameter.

[0126] Example 11 includes the system of any of Examples 9-10, wherein the at least one master unit is configured to receive the at least one configuration parameter from the SMO entity, and to configure the one or more nodes based on the at least one configuration parameter.

[0127] Example 12 includes the system of any of Examples 9-11, wherein the DAS is configured to send an acknowledgement message to the SMO entity in response to receiving the at least one configuration parameter. [0128] Example 13 includes the system of any of Examples 9-12, wherein the one or more nodes includes at least one intermediate combining node (ICN), at least one aggregation switch, or at least one access switch.

[0129] Example 14 includes the system of any of Examples 9-13, wherein the SMO entity is configured to determine the at least one configuration parameter based on a combination of parameters received from at least one central unit (CU), at least one distributed unit (DU), and the DAS.

[0130] Example 15 includes the system of any of Examples 9-14, wherein the SMO entity comprises an element management system (EMS) coupled to a radio access network intelligent controller, wherein the EMS is directly coupled to the DAS via at least one 01/02 interface, wherein the DAS is configured to provide the at least one operational parameter and/or the at least one activity parameter to the radio access network intelligent controller, wherein the EMS is configured to provide the at least one configuration parameter to the DAS via the at least one 01/02 interface.

[0131] Example 16 includes the system of any of Examples 9-15, wherein the DAS is a virtual DAS (vDAS), wherein the at least one master unit is implemented by at least one virtual network function (VNF).

[0132] Example 17 includes a program product comprising a non-transitory processor-readable medium on which program instructions, configured to be executed by at least one processor, are embodied, wherein when executed by the at least one processor, the program instructions cause the at least one processor to: provide, from at least one interface that directly couples a distributed antenna system (DAS) to a service, management, and orchestrator (SMO) entity, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS, wherein the one or more nodes of the DAS includes at least one of: at least one master unit or at least one of a plurality of radio units; receive, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the operational parameters and/or activity parameters of the one or more nodes, wherein the at least one configuration parameter represents a change in operation configuration for the one or more nodes; and configure the one or more nodes based on the at least one configuration parameter. [0133] Example 18 includes the program product of Example 17, wherein the program instructions cause the at least one processor to set at least one of the plurality of radio units in a low-power mode, wherein while in the low-power mode, the at least one radio unit does not radiate RF signals.

[0134] Example 19 includes the program product of any of Examples 17-18, wherein the program instructions cause the at least one processor to adjust an electrical beamtilt of at least one of the plurality of radio units.

[0135] Example 20 includes the program product of any of Examples 17-19, wherein the at least one interface comprises an 01 or 02 interface.

[0136] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, which is calculated to achieve the same purpose, may be substituted for the specific embodiments shown. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof.

Claims

CLAIMS What is claimed is:

1. A method for reducing energy consumption in a distributed antenna system (DAS), wherein the DAS includes at least one master unit communicatively coupled to a plurality of radio units, wherein the at least one master unit is configured to receive downlink signals from at least one base station entity and to generate downlink transport signals from the downlink signals, wherein the plurality of radio units is configured to radiate radio frequency (RF) signals based on the downlink transport signals to user equipment, the method comprising: providing, from at least one interface that directly couples the DAS to a service, management, and orchestrator (SMO) entity, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS, wherein the one or more nodes of the DAS includes at least one of: the at least one master unit or at least one of the plurality of radio units; receiving, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the at least one operational parameter and/or the at least one activity parameter of the one or more nodes, wherein the at least one configuration parameter represents a change in operation configuration for the one or more nodes; and configuring the one or more nodes based on the at least one configuration parameter.

2. The method of claim 1, wherein the at least one configuration parameter is based on at least one energy savings policy determined by the SMO entity, wherein the at least one energy savings policy, wherein by implementing the at least one energy savings policy, the DAS is configures a reduction in power consumption for the at least one radio unit.

3. The method of claim 1, wherein configuring the one or more nodes based on the at least one configuration parameter comprises setting at least one of the plurality of radio units in a low-power mode, wherein while in the low-power mode, the at least one radio unit does not radiate RF signals.

4. The method of claim 1, wherein configuring the one or more nodes based on the at least one configuration parameter comprises adjusting an electrical beamtilt of at least one of the plurality of radio units.

5. The method of claim 1, wherein configuring the one or more nodes based on the at least one configuration parameter comprises each radio unit associated with a cell to an inactive mode, thereby rendering the cell inactive.

6. The method of claim 1, wherein configuring the one or more nodes based on the at least one configuration parameter comprises configuring the one or more nodes via at least one of: a DAS management controller communicatively coupled to the one or more nodes, the at least one master unit, or the SMO entity.

7. The method of claim 1, wherein the at least one interface that directly couples the DAS to the SMO entity include an 01 or 02 interface.

8. The method of claim 1, wherein the at least one operational parameter and/or the at least one activity parameter is reported in a management plane by each of the plurality of radio units.

9. A system, comprising: a distributed antenna system (DAS) directly coupled to a service, management, and orchestration (SMO) entity via one or more interfaces, the DAS comprising: at least one master unit, wherein the at least one master unit is configured to receive downlink signals from at least one base station entity and to generate downlink transport signals from the downlink signals; a plurality of radio units communicatively coupled to the at least one master unit, wherein the plurality of radio units is configured to radiate radio frequency (RF) signals based on the downlink transport signals to user equipment; wherein the DAS is configured to: provide, from the at least one interface, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS, wherein the one or more nodes of the DAS includes at least one of the at least one master unit or at least one of the plurality of radio units; receive, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the at least one operational parameter and/or the at least one activity parameter of the one or more nodes, wherein the at least one configuration parameter represents a change in operation configuration for the one or more nodes; and configure the one or more nodes based on the at least one configuration parameter.

10. The system of claim 9, further comprising a DAS management controller communicatively coupled to the one or more nodes, wherein the DAS management controller is configured to receive the at least one configuration parameter from the SMO entity, and to configure the one or more nodes based on the at least one configuration parameter.

11. The system of claim 9, wherein the at least one master unit is configured to receive the at least one configuration parameter from the SMO entity, and to configure the one or more nodes based on the at least one configuration parameter.

12. The system of claim 9, wherein the DAS is configured to send an acknowledgement message to the SMO entity in response to receiving the at least one configuration parameter.

13. The system of claim 9, wherein the one or more nodes includes at least one intermediate combining node (ICN), at least one aggregation switch, or at least one access switch.

14. The system of claim 9, wherein the SMO entity is configured to determine the at least one configuration parameter based on a combination of parameters received from at least one central unit (CU), at least one distributed unit (DU), and the DAS.

15. The system of claim 9, wherein the SMO entity comprises an element management system (EMS) coupled to a radio access network intelligent controller, wherein the EMS is directly coupled to the DAS via at least one 01/02 interface, wherein the DAS is configured to provide the at least one operational parameter and/or the at least one activity parameter to the radio access network intelligent controller, wherein the EMS is configured to provide the at least one configuration parameter to the DAS via the at least one 01/02 interface.

16. The system of claim 9, wherein the DAS is a virtual DAS (vDAS), wherein the at least one master unit is implemented by at least one virtual network function (VNF).

17. A program product comprising a non-transitory processor-readable medium on which program instructions, configured to be executed by at least one processor, are embodied, wherein when executed by the at least one processor, the program instructions cause the at least one processor to: provide, from at least one interface that directly couples a distributed antenna system (DAS) to a service, management, and orchestrator (SMO) entity, at least one operational parameter and/or at least one activity parameter of one or more nodes of the DAS, wherein the one or more nodes of the DAS includes at least one of: at least one master unit or at least one of a plurality of radio units; receive, from the at least one interface that directly couples the DAS to the SMO entity, at least one configuration parameter in response to providing the operational parameters and/or activity parameters of the one or more nodes, wherein the at least one configuration parameter represents a change in operation configuration for the one or more nodes; and configure the one or more nodes based on the at least one configuration parameter.

18. The program product of claim 17, wherein the program instructions cause the at least one processor to set at least one of the plurality of radio units in a low-power mode, wherein while in the low-power mode, the at least one radio unit does not radiate RF signals.

19. The program product of claim 17, wherein the program instructions cause the at least one processor to adjust an electrical beamtilt of at least one of the plurality of radio units.

20. The program product of claim 17, wherein the at least one interface comprises an 01 or 02 interface.