Patent Description:
A DAS is typically controlled by various software applications executed by a DAS controller which is implemented within a master unit of the DAS. For example, the master unit may comprise rack mounted controller hardware that includes a processor that executes the various functions of the DAS controller. In some systems, the DAS controller may be implemented by electronic components and processors located directly on the backplane of the DAS master unit. Functions performed by the DAS controller typically includes applications for managing aspects of controlling the DAS such as, but not limited to, hardware population, cabling, managing software updates, managing and maintaining a database of DAS hardware configuration, uplink and downlink RF component configurations, and overall system configuration, leveling of uplink and downlink RF signals, hardware diagnostics, generating and distributing alarms, and maintaining a log of alarms in a database on the DAS controller. The DAS controller typically also includes an SNMP interface providing operations and maintenance (O&M) access to the system operators, and may include a server providing a Web page interface for administration of the DAS. In short, the DAS controller implements the logic for controlling the signal processing and forwarding behavior of RF traffic through the DAS between the one or more base stations and user devices which are in wireless communication with the plurality of remote antenna units. This logic may be referred to as the DAS "control plane. " In contrast, the DAS "user plane" provides the transport platform that forwards the RF traffic through the DAS according to the directions provided to the DAS user plane by the DAS control plane.

In that art today, both the control plane and user plane comprise hardware specific software that utilizes low level software that directly interfaces with the DAS hardware electronics, such a memories, registers, interrupts, and the like. This hardware specific software would be supplied by the DAS developer and provided to the operator at the time the DAS hardware is installed. As a result, a telecommunications system operator that owns and operates multiple DAS installations, not only needs to access each DAS installation separately to make updates, reconfigurations, or respond to alarm messages, but they also need maintain familiarity with the software and user interfaces associated with each installation. Moreover, scalability of the control plane at each DAS installation is limited by processing resources present and available for the DAS controller on the DAS hardware, thus potentially limiting the ability of a DAS operator to implement new protocols and standards and/or address increasing RF traffic demands.

For the reasons stated above and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the specification, there is a need in the art for cloud network implementation for a distributed antenna system control plane. <CIT>, relates to an interface for processing digital signals in a standardized format in a DAS. One example includes a unit disposed in a DAS. The unit includes an interface section and an output section. The interface section is configured for outputting a first complex digital signal and a second complex digital signal. The first complex digital signal is generated from a digital signal in a standardized format received from a digital base station. The output section is configured for combining the first complex digital signal and the second complex digital signal into a combined digital signal. The output section is also configured for outputting the combined digital signal. The combined digital signal comprises information to be wirelessly transmitted to a wireless user device. <CIT>, relates to power management subsystems for a DAS or other telecommunication system. The power management subsystem can include a measurement module and an optimization module. The measurement module can monitor a utilization metric for a remote unit in the DAS or other telecommunication system. The power optimization module can determine whether the remote unit is underutilized based on the monitored utilization metric. The power optimization module can configure the remote unit for a low-power operation in response to determining that the remote unit is underutilized.

The invention is defined by the accompanying claims. The Embodiments of the present disclosure provide for cloud network implementation for a distributed antenna system control plane and will be understood by reading and studying the following specification.

In one embodiment, a DAS architecture comprises: a DAS cloud computing network; a first distributed antenna system comprising at least a first user plane, wherein the first user plane includes uplink circuity and downlink circuity, wherein the uplink circuity forwards uplink radio frequency traffic from at least one remote antenna unit of the first distributed antenna system to at least one master unit of the first distributed antenna system, wherein the downlink circuity forwards downlink radio frequency traffic from the least one master unit to the at least one remote antenna unit; wherein the DAS cloud computing network comprises a control plane in communication with the first user plane of the first distributed antenna system through a network; wherein the first user plane comprises a high level protocol interface abstraction layer coupled to the network and processes and forwards the uplink and downlink radio frequency traffic based on configuration commands received from the control plane via the high level protocol interface abstraction layer.

Embodiments of the present disclosure can be more easily understood and further advantages and uses thereof more readily apparent, when considered in view of the description of the preferred embodiments and the following figures in which:.

In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize features relevant to the present disclosure. Reference characters denote like elements throughout figures and text.

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 specific illustrative embodiments in which the embodiments may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments, and it is to be understood that other embodiments may be utilized and that logical, mechanical and electrical changes may be made without departing from the scope of the present disclosure. The following detailed description is, therefore, not to be taken in a limiting sense.

Embodiments of the present disclosure address limitations of DAS controllers in the art today through the separation of DAS control and user planes by the introduction of high level hardware access protocol interface and by off-boarding the DAS control plane functionality from the local DAS hardware and implementing the DAS controller either as virtual machine (VM) executed in a cloud network or as DAS applications offered as a cloud service by the cloud network. In some embodiments, an interface between the control plane and user plane is achieved using high level command and response protocols that are non-hardware specific. That is, the interface between the control and the user plane provides high level description of data and commands to control the user plane and exchange information. The user plane processes and forwards uplink and downlink radio frequency traffic based on configuration messages received from a control plane. The interface between further provides an abstraction from the underlying hardware so that the DAS controller does not require any detailed knowledge of the hardware to be configured and controlled, thus avoiding the need for the DAS controller to utilize low level hardware command sequences to communicate instructions to the user plane. Moreover, with such an abstraction, digital as well as analog user plane hardware can be used transparently via the high level protocol interface.

<FIG> is a diagram illustrating a DAS architecture <NUM> for one embodiment of the present disclosure where the DAS controller and user planes are separated. As illustrated in <FIG>, a user plane <NUM> is implemented in DAS hardware <NUM> by executing hardware specific user plane applications <NUM> that process and transport RF communication traffic between one or more wireless network base stations <NUM> (shown as communication traffic <NUM>) and user equipment <NUM> (shown as communication traffic <NUM>). As further discussed below, the user plane applications <NUM> may be executed by controllers in DAS master units, remote antenna units, extension and/or expansion units, or some combination thereof. Rather than also being implemented in DAS hardware <NUM>, the control plane <NUM> is implemented virtually in by a DAS cloud computing network <NUM> (referred to herein as a "DAS cloud" <NUM>) in order to realize the DAS controller <NUM>. That is, one or more network nodes of the DAS cloud <NUM> may comprise processors that execute the functions described herein of the control plane <NUM> and DAS controller <NUM>. Moreover, the storage for persistent system level data (previously maintained on DAS hardware <NUM>) may also be separated into the DAS cloud <NUM> and maintained on a data plane <NUM> (for example, a shared database) on DAS cloud <NUM> that is accessible from the DAS controller <NUM> via a defined data access protocol. In some embodiments, the data plane <NUM> is also separate from the DAS controller <NUM> within DAS cloud <NUM>, to allow for moving database tables to dedicated machines (either real or virtual machines) and thus further improve performance and scalability. Additionally, databases can be shared between DAS cloud <NUM> components such as, but not limited to, Network Configuration Services, O&M services, the DAS Controller and the WWW Backend Server which avoids redundancies in data and further speeds up the data access.

As shown in <FIG>, the user plane <NUM> implemented in DAS hardware <NUM>, and the DAS controller <NUM> implemented in DAS cloud <NUM> are communicatively coupled via a network <NUM> (which may comprise an Internet Protocol (IP) network such as the Internet, for example). In one embodiment, the user plane <NUM> includes a high level command and response protocol interface <NUM> (referred to herein as "high level protocol interface") through which the DAS controller <NUM> communicates to the user plane <NUM>. High level protocol interface <NUM> provides an abstraction layer through which the DAS controller <NUM> can send non-hardware specific commands and data in order to configure operation of the user plane <NUM>. The high level protocol interface <NUM>, in contrast, can communicate with the components of DAS hardware <NUM>, either directly or indirectly, to configure the DAS hardware <NUM> to operate as directed by the DAS controller <NUM>. For example, the DAS controller <NUM> may send a command to the user plane <NUM> via high level protocol interface <NUM> to vary the transmit power of a first cellular band, designated RF band #<NUM> for example. In doing so, the DAS controller <NUM> may simply pass to the high level protocol interface <NUM> the designated band "RF band #<NUM>" and the desired transmit power, without the need for any underlying knowledge about which hardware registers, amplifiers, processors, etc. of DAS hardware <NUM> handle the processing of RF band #<NUM>. Instead, the high level protocol interface <NUM> interprets such instructions into DAS hardware <NUM> specific instructions in order to carry out the high-level commands received form the DAS controller <NUM>. In the same way, hardware level alarms or messages generated by the DAS hardware <NUM> may be received by the high level protocol interface <NUM> and translated to a high-level alarm notification to the DAS controller <NUM> over network <NUM>.

In some embodiments, the DAS cloud <NUM> may further comprise servers or network nodes. In one embodiment, the network nodes may comprise processors that implement network configuration services <NUM>, an internet World Wide Web (WWW) backend server <NUM>, a northbound interface (NBI) to operations and maintenance service <NUM>, or both, with which the DAS operator may interact with, and control, any aspect of the control plane <NUM> and/or data plane <NUM>. Such a configuration supports the provision of user interfaces according to the Model View Controller (MVC) software architecture pattern which allows for clear separation between of the Web Front End (Client) and Web Backend.

It should be understood that architecture <NUM> may be expanded in other embodiments to include multiple user plane entities which are managed by a control plane <NUM> from the DAS cloud <NUM>. That is, one or more additional instances of user plane entities, which may be operated either in conjunction with DAS hardware <NUM> or completely independent from DAS hardware <NUM>, may be managed and operated using architecture <NUM>. For example, in <FIG>, one or more additional user planes <NUM> may be communicatively coupled to the DAS cloud <NUM> via network <NUM> and operated in the same manner as described above regarding user plane <NUM>. In the embodiment shown in <FIG>, the additional user planes <NUM> may be executed by DAS hardware <NUM> which is separate and independent from DAS hardware <NUM>. However, in other embodiments, one or more of the additional user planes <NUM> may also be executed by DAS hardware <NUM>. Each of the additional user planes <NUM> comprises a high level command and response protocol interface <NUM> and may be communicatively coupled to the DAS cloud <NUM> via network <NUM> and operated in the same manner as described above regarding DAS hardware <NUM> and user plane <NUM>. In this way, multiple DAS installations may be managed by an operator via the DAS cloud <NUM> without the need to connect to and utilize hardware specific software for each installation. Moreover, in some embodiments, the storage for persistent system level data for DAS hardware <NUM> and DAS hardware <NUM> (and/or any other DAS installations) is maintained together on data plane <NUM>, thus providing a database that comprises a shared set of tables for all pertinent information relevant to the operator's communication system.

The separation of the control and user planes of a DAS as illustrated by DAS architecture <NUM> supports scalability with respect to increasing RF communications traffic between BTS and user devices by enabling the DAS operator to add user plane nodes without changing the number of controllers in the network. Other benefits include a clear control and O&M interface between control plane and user plane, the flexibility to locate and scale the control plane and control plane resources independent of the processing resources available at the DAS, and independent evolution and development of the control plane and user plane functions. In some embodiments, the control plane implemented in the DAS cloud can be technology agnostic and control analog as well as digital user planes, and used in conjunction with multiple user plane entities. Moreover, certain functions of a DAS control plane are rarely used, or may even just be used once at the time of DAS commissioning. With such functions implemented by software executed in the DAS cloud, a single installation of the software can be shared by multiple user plane entities.

As mentioned above, in alternative embodiments, a DAS controller <NUM> may be realized either by establishing one or more DAS controller virtual machines in DAS cloud <NUM>, or by directly providing DAS applications associated with DAS controller functions as services available from DAS cloud <NUM>. It should be understood that the virtualized DAS Controllers and Cloud Services, and network nodes, servers, gateways, and/or other components comprising the DAS cloud <NUM> may be executed from a data center of a DAS operator and/or any other cloud service provider. In fact, the physical location of the control plane/DAS Controller is no longer relevant as only the user plane <NUM> and RF components comprising the DAS hardware <NUM> need to be located at the DAS site. DAS cloud <NUM> resources can be allocated on demand and expenses incurred from running the DAS Controller, System Configuration, and Network Element Management Functions, for example, can be tailored to the needs of the system operator.

<FIG> is a block diagram illustrating an example DAS <NUM> (also referred to herein as a DAS installation) of one embodiment of the present disclosure. DAS <NUM> comprises one or more master units <NUM> that are communicatively coupled to one or more remote antenna units <NUM> via one or more communication links <NUM>. In various different embodiments, the communication links <NUM> may comprise wireless communication links, cables (i.e. wired communication links), or some combination thereof. As used herein, the term cable is used generically and may refer to either electrical or fiber optic cables, or hybrid cables comprising both electrical conductors and optical fibers. It should be understood that DAS <NUM> may provide wireless telecommunication services to a building, plant, campus, transportation hub, tunnel, or any other type of facility. In some embodiments, the communication links <NUM> discussed herein may each operate bidirectionally with downlink and uplink communications carried over the link. It should also be understood, however, that in other embodiments, a communication link <NUM> may itself further comprise a pair of links including, for example, an uplink cable for uplink communication, and a downlink cable for downlink communication. Each remote antenna unit <NUM> can be communicatively coupled directly to one or more of the master units <NUM> or indirectly via one or more other remote antenna units <NUM> and/or via one or more intermediary or expansion units <NUM>. In some embodiments, DAS <NUM> may further include one or more extension units <NUM> that are communicatively coupled to a remote antenna unit <NUM> to further extend coverage. As illustrated in <FIG>, with embodiments of the present disclosure the control plane <NUM> is separated from user plane <NUM> by implementing the control plane <NUM> as a DAS controller on a separate machine (as shown at <NUM>) and/or in a virtualized environment or in the cloud as discussed in greater detail below. Regardless of where or how the functions of a DAS controller <NUM> are specifically implemented, control plane <NUM> functions for the DAS <NUM> are executed on a platform separate from the DAS <NUM> hardware and their associated services provided to each of the Master Unit <NUM>, Remote Antenna Units <NUM>, and Expansion Units <NUM> and Extension Units <NUM> (when present) via the high level protocol interface <NUM>.

Each master unit <NUM> is communicatively coupled to one or more base stations <NUM> (such as the wireless network base stations <NUM> described in <FIG>). In some embodiments, one or more of the base stations <NUM> can be co-located with the respective master units <NUM> to which it is coupled (for example, where the base station <NUM> is dedicated to providing base station capacity to the DAS <NUM> and is coupled to the respective master units <NUM>). Also, one or more of the base stations <NUM> can be located remotely from the respective master units <NUM> to which it is coupled (for example, where the base station <NUM> provides base station capacity to an area beyond the coverage area of the DAS <NUM>). In this latter case, the master unit <NUM> can be coupled to a donor antenna and repeater or bidirectional amplifier in order to wirelessly communicate with the remotely located base station <NUM>.

In this exemplary embodiment, the base stations <NUM> include one or more base stations that are used to provide public and/or private safety wireless services (for example, wireless communications used by emergency services organizations (such as police, fire and emergency medical services) to prevent or respond to incidents that harm or endanger persons or property. Such base stations are also referred to here as "safety wireless service base stations" or "safety base stations. " The base stations <NUM> also can include, in addition to safety base stations, one or more base stations that are used to provide commercial cellular wireless service. Such base stations are also referred to here as "commercial wireless service base stations" or "commercial base stations.

The base stations <NUM> can be coupled to the master units <NUM> using a network of attenuators, combiners, splitters, amplifiers, filters, cross-connects, etc., (sometimes referred to collectively as a "point-of-interface" or "POI"). This network can be included in the master units <NUM> and/or can be separate from the master units <NUM>. This is done so that, in the downlink, the desired set of RF channels output by the base stations <NUM> can be extracted, combined, and routed to the appropriate master units <NUM>, and so that, in the upstream, the desired set of carriers output by the master units <NUM> can be extracted, combined, and routed to the appropriate interface of each base station <NUM>. It is to be understood, however, that this is one example and that other embodiments can be implemented in other ways.

As shown in <FIG>, in general, each master unit <NUM> comprises downlink DAS circuitry <NUM>, uplink DAS circuitry <NUM> and a controller <NUM> (that together comprise a segment of the DAS hardware <NUM>) and hardware specific applications <NUM> that execute on the controller <NUM> (for example to implement the high level protocol interface <NUM>). These elements together define the user plane <NUM> within the master unit <NUM> that processes and transports RF communications traffic <NUM> and <NUM> between the one or more wireless network base stations <NUM> and user equipment <NUM>. Control plane services for the DAS <NUM> are separated from the master unit <NUM> and implemented elsewhere, such as by DAS controller <NUM> described below. High level protocol interface <NUM> provides the necessary connectivity between master unit <NUM> and systems implementing the control plane services.

Downlink DAS circuitry <NUM> is configured to receive one or more downlink signals from one or more base stations <NUM>. These signals are also referred to here as "base station downlink signals. " Each base station downlink signal includes one or more radio frequency channels used for communicating in the downlink direction with user equipment <NUM> (such as tablets or cellular telephone, for example) over the relevant wireless air interface. Typically, each base station downlink signal is received as an analog radio frequency signal, though in some embodiments one or more of the base station signals are received in a digital form (for example, in a digital baseband form complying with the Common Public Radio Interface ("CPRI") protocol, Open Radio Equipment Interface ("ORI") protocol, the Open Base Station Standard Initiative ("OBSAI") protocol, or other protocol). The downlink DAS circuitry <NUM> in each master unit <NUM> is also configured to generate one or more downlink transport signals derived from one or more base station downlink signals and to transmit one or more downlink transport signals to one or more of the remote antenna units <NUM>. Each master unit <NUM> also comprises the uplink DAS circuitry <NUM> that is configured to receive the respective uplink transport signals transmitted to it from one or more remote antenna units <NUM> and to use the received uplink transport signals to generate one or more base station uplink radio frequency signals that are provided to the one or more base stations <NUM>. Typically, this involves, among other things, combining or summing uplink signals received from multiple remote antenna units <NUM> in order to produce the base station signal provided to each base station <NUM>. Each base station uplink signal includes one or more of the uplink radio frequency channels used for communicating with user equipment <NUM> over the wireless air interface. In this way, the DAS <NUM> increases the coverage area for the uplink capacity provided by the base stations <NUM>.

As shown in <FIG>, each remote antenna unit <NUM>, in general, comprises downlink DAS circuitry <NUM>, uplink DAS circuitry <NUM> and a controller <NUM> (that together comprise a segment of the DAS hardware <NUM>) and hardware specific applications <NUM> that execute on the controller <NUM> (for example to implement the high level protocol interface <NUM>). Downlink DAS circuitry <NUM> is configured to receive the downlink transport signals transmitted to it from one or more master units <NUM> and to use the received downlink transport signals to generate one or more downlink radio frequency signals that are radiated from one or more antennas <NUM> associated with that remote antenna unit <NUM> for reception by user equipment <NUM>. These downlink radio frequency signals are analog radio frequency signals and are also referred to here as "remote downlink radio frequency signals. " Each remote downlink radio frequency signal includes one or more of the downlink radio frequency channels used for communicating with user equipment <NUM> over the wireless air interface.

Also, each remote antenna unit <NUM> comprises uplink DAS circuitry <NUM> that is configured to receive via antenna(s) <NUM> one or more uplink radio frequency signals transmitted from the user equipment <NUM>. These signals are analog radio frequency signals and are also referred to here as "remote uplink radio frequency signals. " Each uplink radio frequency signal includes one or more radio frequency channels used for communicating in the uplink direction with user equipment <NUM> over the relevant wireless air interface. The uplink DAS circuitry <NUM> in each remote antenna unit <NUM> is also configured to generate one or more uplink transport signals derived from the one or more remote uplink radio frequency signals and to transmit one or more uplink transport signals to one or more of the master units <NUM>.

As shown in <FIG>, each expansion unit <NUM>, in general, comprises downlink DAS circuitry <NUM>, uplink DAS circuitry <NUM> and a controller <NUM> (that together comprise a segment of the DAS hardware <NUM>) and hardware specific applications <NUM> that execute on the controller <NUM> (for example to implement the high level protocol interface <NUM>). Downlink DAS circuitry <NUM> that is configured to receive the downlink transport signals transmitted to it from the master unit <NUM> (or other expansion unit <NUM>) and transmits the downlink transport signals to one or more remote antenna units <NUM> or other downstream intermediary units <NUM>. Each expansion unit <NUM> comprises uplink DAS circuitry <NUM> that is configured to receive the respective uplink transport signals transmitted to it from one or more remote antenna units <NUM> or other downstream intermediary units <NUM>, combine or sum the received uplink transport signals, and transmit the combined uplink transport signals upstream to the master unit <NUM> or other expansion unit <NUM>. In some embodiments, one or more remote antenna units <NUM> may be coupled to the one or more master units <NUM> via one or more other remote antenna units <NUM> (for examples, where the remote antenna units <NUM> are coupled together in a daisy chain or ring topology). In such embodiments, an expansion unit <NUM> may be implemented using a remote antenna units <NUM>.

As shown in <FIG>, each extension unit <NUM>, in general, comprises downlink DAS circuitry <NUM>, uplink DAS circuitry <NUM> and a controller <NUM> (that together comprise a segment of the DAS hardware <NUM>) and hardware specific applications <NUM> that execute on the controller <NUM> (for example to implement the high level protocol interface <NUM>). Downlink DAS circuitry <NUM> is configured to receive the downlink transport signals transmitted to it from a remote antenna unit <NUM> and to use the received downlink transport signals to generate one or more downlink radio frequency signals that are radiated from one or more antennas <NUM> associated with that extension unit <NUM> for reception by user equipment <NUM>. Each downlink radio frequency signal includes one or more of the downlink radio frequency channels used for communicating with user equipment <NUM> over the wireless air interface. In this way, the DAS <NUM> may even further increase the coverage area and/or capacity for the downlink capacity provided by the base stations <NUM>. Each extension unit <NUM> may further comprise uplink DAS circuitry <NUM> that is configured to receive via antenna(s) <NUM> one or more uplink radio frequency signals transmitted from the user equipment <NUM>. These signals are analog radio frequency signals and are also referred to here as "uplink radio frequency signals. " Each uplink radio frequency signal includes one or more radio frequency channels used for communicating in the uplink direction with user equipment <NUM> over the relevant wireless air interface. The uplink DAS circuitry <NUM> in each extension unit <NUM> may also be configured to generate one or more uplink transport signals derived from the one or more remote uplink radio frequency signals and to transmit one or more uplink transport signals to the remote antenna unit <NUM> to which it is coupled. In some embodiments, the uplink DAS circuitry <NUM> in a remote antenna unit <NUM> may be further configured to receive the respective uplink transport signals transmitted to it from an extension unit <NUM> and to use the received uplink transport signals to generate uplink radio frequency signals that are provided to the master unit <NUM>.

As shown in <FIG>, in one embodiment, a DAS Controller <NUM>, in general may comprise a controller <NUM> that executes the DAS Control Plane Services <NUM> to realize the control plane function for DAS <NUM> either on a separate machine, in a virtualized environment or in the cloud. Moreover, the high level protocol interface <NUM> in the DAS Controller <NUM> provides the necessary connectivity between DAS Controller <NUM> and the DAS <NUM> user plane functions that are executed on the various DAS <NUM> hardware components. In one embodiment, the DAS Controller <NUM> may comprise a modem <NUM> in order to communicatively couple DAS Controller <NUM> to network <NUM>.

The downlink DAS circuitry <NUM>, <NUM>, <NUM>, and <NUM> and uplink DAS circuitry <NUM>, <NUM>, <NUM> and <NUM> in each master unit <NUM>, remote antenna unit <NUM>, expansion unit <NUM>, and extension unit <NUM>, respectively, can comprise one or more appropriate connectors, attenuators, combiners, splitters, amplifiers, filters, duplexers, analog-to-digital converters, digital-to-analog converters, mixers, field-programmable gate arrays (FPGAs), microprocessors, transceivers, framers, etc., to implement the features described above. Also, the downlink DAS circuitry <NUM>, <NUM>, <NUM>, and <NUM> and uplink DAS circuitry <NUM>, <NUM>, <NUM> and <NUM> may share common circuitry and/or components. For example, some components (such as duplexers) by their nature are shared among the downlink DAS circuitry <NUM>, <NUM>, <NUM>, and <NUM> and uplink DAS circuitry <NUM>, <NUM>, <NUM> and <NUM>.

The DAS <NUM> can use either digital transport, analog transport, or combinations of digital and analog transport for generating and communicating the transport signals between the base station <NUM>, the master units <NUM>, the remote antenna units <NUM>, and any expansion units <NUM>. For the purposes of illustration, some of the embodiments described here are implemented using analog transport over optical cables. However, it is to be understood that other embodiments can be implemented in other ways, for example, in DASs that use other types of analog transport (for example, using other types of cable and/or using analog transport that makes use of frequency shifting), digital transport (for example, where digital samples indicative of the analog base station radio frequency signals and analog remote radio frequency signals are generated and communicated between the master units <NUM> and the remote antenna units <NUM>), or combinations of analog and digital transport.

Each unit <NUM>, <NUM>, <NUM>, <NUM> in the DAS <NUM> can also comprise a respective controller <NUM>, which as discussed above, executes the hardware specific user plane applications <NUM> and high level protocol interface <NUM> for the user plane <NUM> implemented within that particular unit. The controller <NUM> is implemented using one or more programmable processors and memory hardware that execute software that is configured to implement the various features described here as being implemented by the controller <NUM>. The controller <NUM>, the various features described here as being implemented by the controller <NUM>, or portions thereof, can be implemented in other ways (for example, in a field programmable gate array (FPGA), application specific integrated circuit (ASIC), etc.). The master unit <NUM> may comprise a modem <NUM> communicatively coupled to network <NUM>. In one embodiment, each unit <NUM>, <NUM>, <NUM>, <NUM> in the DAS <NUM> is also configured to send and receive management and control data with control plane <NUM> via a high level protocol implemented by the high level protocol interface <NUM>.

<FIG> illustrates an example embodiment of a DAS architecture <NUM> providing an example implementation of the DAS architecture <NUM> discussed with respect to <FIG>. In the embodiment DAS architecture <NUM> one or more DAS Controllers are implemented as DAS Controller Virtual Machine(s) <NUM> within DAS cloud <NUM>. In this embodiment, the web backend is realized using a Web Backend Virtual Machine (VM) <NUM> (i.e., a web server) and the data plane <NUM> is realized using a Data Base Virtual Machine (VM) <NUM> which comprises the shared database <NUM>. Communication between the DAS Controller Virtual Machine(s) <NUM>, the Web Backend Virtual Machine <NUM>, and the Shared Database <NUM> may be implemented by a Message and Data Bus <NUM>, through which every functional entity of DAS cloud <NUM> can access data and send commands to any other entity coupled to bus <NUM>. In various embodiments, the Message and Data Bus <NUM> may be implemented, for example, using ethernet or any other type of communications technology.

As shown in <FIG>, DAS architecture <NUM> may include multiple user plane entities (shown at <NUM>) communicatively coupled to DAS cloud <NUM> via a communications network <NUM>. Each of the user plane entities <NUM> may comprise a user plane <NUM> such as shown in <FIG> and correspond to the user plane of a DAS as shown in <FIG>. In some embodiments, communications between the DAS Controller Virtual Machines <NUM> and the user planes <NUM> may be based on IP protocols and/or secured by VPN tunnels and/or firewalls. In some embodiments, DAS cloud <NUM> further comprises a virtual Ethernet switch <NUM> that switches Ethernet packets between the user plane entities <NUM> and the DAS Controller Virtual Machine <NUM> with which they are associated. There may exist a one-to-one correspondence between one of the DAS Controller Virtual Machines <NUM> and a respective one of the user planes <NUM>. However, in other embodiments that need not be the case. For example, any one of the DAS Controller Virtual Machines <NUM> may work in conjunction with two or more of the user planes <NUM>. Similarly, any one of the user planes <NUM> may be subdivided into a multiple logical user planes each associated with a separate one of the DAS Controller Virtual Machines <NUM>. As shown in the embodiment of <FIG>, the DAS architecture <NUM> may further comprise a System Configuration Virtual Machine <NUM>, and a Network Element Management Virtual Machine <NUM>, each implemented by DAS cloud <NUM> and coupled to Message and Data Bus <NUM>.

Integration of the DAS Controller functionality and sharing of DAS system data in DAS cloud <NUM> with the System Configuration Virtual Machine <NUM> and Network Element Management Virtual Machine <NUM> may be achieved by sharing common data stored in the shared database <NUM> and/or by using the same web backend <NUM> and a web frontend <NUM> (i.e., a WWW client) for user access. In some embodiments, the web frontend client <NUM> may be executed by a human interface device integrated into a server or other node coupled to DAS cloud <NUM>.

System Configuration Virtual Machine <NUM> executes one or more applications which may be used to configure operation of various aspects of the DAS cloud <NUM>. For example, in one embodiment, the System Configuration Virtual Machine <NUM> executes applications that manage functions such as, but not limited to: RF Network Planning, RF Output Power Management, Optical Transport Capacity Management, Service Distribution Configuration, Hardware Configuration & bill-of-material (BOM), Inventory, and DAS Cloud user rights management. In some embodiments, the Network Element Management Virtual Machine <NUM> provides the interface to the proprietary operations and maintenance services <NUM> for the network operator to control their DAS installations (for example via a northbound interface (NBI) to operations and maintenance service). The Network Element Management Virtual Machine <NUM> may execute one or more applications to provide functions such as, but not limited to: Fault Management (which may include generating, distributing and logging active alarms, alarm history, remedy, acknowledgement, etc.), Configuration Management (which may include hardware and RF electronics connectivity and alarm parameter changes, for example), Inventory Management (which may include an inventory of DAS hardware and software components and change history), Performance Management (which may include Alarm Statistics, hardware and RF component data graphs, etc.), User Management (which may include role and rights administration of user accounts for the system operator), Security Management (which may include VPN management, NE Base Image updates, control of software / application inventory), and or application or script processing for automation of routine tasks (such as software distribution and activation, NE backup, managing bulk configuration changes, etc.).

As there are common functionalities performed by the System Configuration Virtual Machine <NUM> and a Network Element Management Virtual Machine <NUM>, with embodiments of the present disclosure, storage of the database tables used by both system in the common data plane <NUM> with common access to shared database <NUM> ensures the data consistency between the applications, (either on the same virtual machine or on different virtual machines) and ensures that updates to data made by one virtual machine is immediately available to the other. In some embodiments, the same access to the shared database <NUM> may be selectively afforded to any component coupled to Message and Data Bus <NUM>.

As mentioned above, access to the common data stored in the shared database <NUM> may also be obtained via a WWW webpage server implemented by web backend <NUM> and accessed by a web frontend client (or web client user interface) <NUM>. Web client user interface <NUM> thus provides a common user interface and single access point for a user to manage the operation and configuration of any user plane entity <NUM>. In one embodiment, the web backend <NUM> may serve web pages associated with each of various DAS applications provided by the virtual machines implemented in the DAS cloud <NUM> (for example, DAS Controller VMs <NUM>, Network Element Management System VM <NUM>, and/or System Configuration VM <NUM>) to the web frontend client <NUM>. In one embodiment, the web backend VM <NUM> may interface with each of the respective DAS applications via a defined Application Programing Interface (API) (for example, using a Representational state transfer API, or JavaScript Object Notation based messaging) to request information and trigger commands and forwards the results to the web frontend client <NUM>. For certain operations the web backend VM <NUM> may also have direct access to the shared database <NUM> rather than depend on access via the virtual machines. In some embodiments, different roles in DAS Commissioning and Operation as well as access control may be handled via user management from the common user interface provided by the web frontend client <NUM>.

The virtualization of the control plane <NUM> functions for execution by the DAS cloud <NUM> saves costs over the need to provide dedicated DAS controllers locally at each DAS installation, and provides the flexibility that one controller can essentially be used to replace multiple traditional DAS control planes. Scalability for a DAS controller <NUM> in DAS architecture <NUM> is also obtained through the ability to simply allocate additional processing resources from within the DAS Cloud <NUM> (for example, additional or more powerful processing units, memory, disk space, etc.) to the virtual machine <NUM> that executes that respective DAS controller.

As mentioned above, in alternative embodiments, a DAS controller <NUM> may be realized either by establishing one or more DAS controller virtual machines in DAS cloud <NUM>, or by directly providing DAS applications associated with DAS controller functions as services available from DAS cloud <NUM>.

<FIG> illustrates an alternative embodiment of a DAS architecture <NUM> for another example implementation of the DAS architecture <NUM>. In DAS architecture <NUM>, the DAS applications associated with the DAS controllers, System Configuration, and Network Element Management functions discussed above are directly provided as services available from applications executed by the DAS cloud <NUM>. That is, the virtualized applications discussed in DAS architecture <NUM> are broken up into single functions that are grouped into separate cloud services <NUM>, <NUM> and <NUM>. Each of the cloud services are in turn implemented by the execution of particular applications by processors on nodes of DAS cloud <NUM>. In the particular implementation shown in <FIG>, the separate cloud services provided by DAS cloud <NUM> are grouped into Network Planning and Configuration Services <NUM> (which may include applications that execute functions such as RF Planning, BOM Creation, Optical Transport Configuration, for example ), DAS Control Plane Services <NUM> (which may include applications that execute functions use at the time a DAS is commissioned, such as hardware population, cabling, leveling, service configuration, for example) and Operation and Maintenance Services <NUM> (which may include applications that execute functions such as RF Monitoring, Alarm functions, Performance Management, and so forth) which may include a northbound interface (NBI) to operations and maintenance service. It should be understood that in other embodiments, these functions may be grouped together differently and/or together with additional functions into any number of distinct cloud services.

In the DAS architecture <NUM>, each of the provided cloud services <NUM>, <NUM>, <NUM> are in communication with the Message and Data Bus <NUM>, along with Web Backend Services <NUM>, and the data plane <NUM> which comprises the shared database <NUM>. Through the Message and Data Bus <NUM> every functional entity of DAS cloud <NUM>, including each of the applications used to provide the cloud services <NUM>, <NUM> and <NUM>, can access data and send commands to any other entity coupled to bus <NUM>. DAS architecture <NUM> may also include multiple user plane entities <NUM> communicatively coupled to DAS cloud <NUM> via a communications network <NUM>. Communications between the cloud services <NUM>, <NUM>, <NUM> and the user planes entities <NUM> may be based on IP protocols and/or secured by VPN tunnels and/or firewalls. In some embodiments, DAS cloud <NUM> in DAS architecture <NUM> may also further comprise virtual Ethernet switch <NUM> that switches Ethernet packets between the user plane entities <NUM> and the cloud services <NUM>, <NUM>, <NUM> that interact with the user plane entities <NUM>.

In the particular DAS architecture <NUM> shown in <FIG>, there is no longer any need for any correspondence between distinct DAS Controllers and respective user plane entities because the cloud services <NUM>, <NUM>, and <NUM> essentially function as a single centralized DAS Controller for all of the user plane entities <NUM>. However, in some embodiments, since cloud services <NUM>, <NUM>, <NUM> may be configured to recognize logical user planes which may comprise the union of two or more of the user planes <NUM>, a subdivision of any one or more of the user planes <NUM>, or combinations thereof. In the same manner as discussed above, sharing of DAS system data in DAS cloud <NUM> across all cloud services may be achieved by sharing common data stored in the shared database <NUM> and/or by using the same web backend <NUM> and a web frontend (i.e., a WWW client) <NUM> for user access. Storage of the database tables used by the cloud services <NUM>, <NUM>, <NUM> in the common data plane <NUM> with common access to shared database <NUM> ensures the data consistency between applications and ensures that updates to data made by one cloud service <NUM>, <NUM>, <NUM> is immediately available to the others. The same access to the shared database <NUM> may be selectively afforded to any component coupled to Message and Data Bus <NUM>.

An advantage of Cloud Services as provided by DAS architecture <NUM> is that DAS Functions traditionally provided by separate DAS controllers can be shared between DAS sites while functional and structural redundancies can be removed. Further the DAS Cloud Services can save resources and be scaled to the needs. For instance, the Planning and Configuration Services <NUM> as well as DAS Control Plane Services <NUM> are processes that typically are only used at the time of a DAS installation. Accordingly, such services may be suspended during normal steady state operation to conserve processing resources.

In various alternative embodiments, system and/or device elements, method steps, or example implementations described throughout this disclosure (such as any of the master units, remote antenna units, expansion units, controllers, circuitry, user planes, control planes, data planes, high level protocol interfaces, cloud networks, virtual machines, switches, cloud services, web backend servers or frontend client, or sub-parts of any thereof, for example) may be implemented at least in part using one or more computer systems, field programmable gate arrays (FPGAs), or similar devices comprising a processor coupled to a memory and executing code to realize those elements, processes, or examples, said code stored on a non-transient hardware data storage device. Therefore other embodiments of the present disclosure may include elements comprising program instructions resident on computer readable media which when implemented by such computer systems, enable them to implement the embodiments described herein. As used herein, the term "computer readable media" refers to tangible memory storage devices having non-transient physical forms. Such non-transient physical forms may include computer memory devices, such as but not limited to punch cards, magnetic disk or tape, any optical data storage system, flash read only memory (ROM), non-volatile ROM, programmable ROM (PROM), erasable-programmable ROM (E-PROM), random access memory (RAM), or any other form of permanent, semi-permanent, or temporary memory storage system or device having a physical, tangible form. Program instructions include, but are not limited to computer-executable instructions executed by computer system processors and hardware description languages such as Very High Speed Integrated Circuit (VHSIC) Hardware Description Language (VHDL).

It should be appreciated that other network architectures may be implemented that still functionally operate in the same manner as described in any of the embodiments described herein. It should also be understood that for any of the embodiments described herein, while the communication links connecting master units and remote antenna units may comprise optical fiber, in other embodiments other wired or wireless communication links, or combinations thereof, may be utilized instead of, or in combination with, optical fiber communication links.

Claim 1:
A distributed antenna system (<NUM>), DAS, the system (<NUM>) comprising:
at least one master unit (<NUM>) configured to receive a base station downlink radio frequency signal and to transmit a base station uplink radio frequency signal;
at least one remote antenna unit (<NUM>) that is communicatively coupled to the at least one master unit (<NUM>), the remote antenna unit (<NUM>) comprising a power amplifier and configured to radiate a remote downlink radio frequency signal from at least one antenna (<NUM>) associated with the remote antenna unit (<NUM>), the remote antenna unit (<NUM>) further configured to receive a remote uplink radio frequency signal from at least one antenna (<NUM>) associated with the remote antenna unit (<NUM>);
at least a first user plane (<NUM>) comprising uplink circuity (<NUM>, <NUM>) and downlink circuity (<NUM>, <NUM>), wherein the uplink circuity (<NUM>, <NUM>) is configured to forward uplink radio frequency traffic from the least one remote antenna unit (<NUM>) to the at least one master unit (<NUM>), wherein the base station uplink radio frequency signal at least in part comprises the uplink radio frequency traffic, wherein the downlink circuity (<NUM>, <NUM>) is configured to forward downlink radio frequency traffic from the least one master unit (<NUM>) to the at least one remote antenna unit (<NUM>), wherein the base station downlink radio frequency signal at least in part comprises the downlink radio frequency traffic;
wherein the first user plane (<NUM>) is in communication with a control plane (<NUM>) via a network, the first user plane (<NUM>) further comprising a high level protocol interface abstraction layer (<NUM>), wherein the control plane (<NUM>) is configured to communicate to the first user plane (<NUM>) by sending from the control plane (<NUM>) to the first user plane (<NUM>), via the high level protocol interface abstraction layer (<NUM>), non-hardware specific commands and data that is adapted to configure operation of the first user plane (<NUM>), wherein the first user plane (<NUM>) is adapted to process and forward the uplink and downlink radio frequency traffic based on configuration commands received from the control plane (<NUM>).