Patent ID: 12207242

DETAILED DESCRIPTION

The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments. Upon reading the following description in light of the accompanying figures, those skilled in the art will understand the concepts of the description and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the description.

Various features and embodiments will now be described with reference to the figures to fully convey the scope of the disclosure to those skilled in the art.

Many aspects will be described in terms of sequences of actions or functions. It should be recognized that in some embodiments, some functions or actions could be performed by specialized circuits, by program instructions being executed by one or more processors, or by a combination of both.

Further, some embodiments can be partially or completely embodied in the form of computer readable carrier or carrier wave containing an appropriate set of computer instructions that would cause a processor to carry out the techniques described herein.

In some alternate embodiments, the functions/actions may occur out of the order noted in the sequence of actions. Furthermore, in some illustrations, some blocks, functions or actions may be optional and may or may not be executed; these are generally illustrated with dashed lines.

The SAS Architecture200is depicted inFIG.2, as proposed by the Federal Communications Commission (FCC) for the 3.5 GHz band. The SAS is a central entity or system for coordinating, authorizing and managing use of the CBRS spectrum, protecting higher tier operations from interference, and maximizing frequency capacity for all CBRS operators. The SAS may be referred to as a controlling node. The SAS administrators will be permitted to charge CBRS operators fees for registration and frequency coordination services. There may be one or more SAS, such as SAS1205and SAS2210connected to each other.

As illustrated inFIG.2, for example, SAS1205is also connected to FCC databases215, an Environmental Sensing Capability (ESC) system220for incumbent detection, an informing incumbent system225, a domain proxy230and CBSDs235(e.g. CBSD4). The Domain Proxy230can be optionally connected to an Element Management System (EMS)240. The EMS240can be connected to a plurality of CBSDs235, such as CBSD1, CBSD2, CBSD3, etc. Each CBSD domain may optionally include some sensing capability systems245(e.g. CBSD sensing).

The FCC requires that transmission equipment with specific, standardized capabilities be employed by CBRS operators for use in the 3.5 GHz band. This equipment is called Citizens Broadband Service Device (“CBSD”). CBSDs are fixed base stations/access points, such as an LTE Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node Bs (also commonly denoted as evolved Node Bs, enhanced Node Bs, eNodeBs, or eNBs) or gNB from New Radio (NR). There are two types of CBDSs: Category A (a lower power CBSD) and Category B (a higher power CBSD). The CBSDs235can only operate under the authority and management of a centralized Spectrum Access System.

CBRS end user devices are controlled by an authorized CBSD. End User Devices (EUD) have the capability to receive and decode information from a CBSD. The users access a communication network through one or more CBSDs and, when granted permission from the SAS, use resources within the shared band.

Some of the SAS' functionalities are as follows:Determine and provide to CBSDs235the permissible channels or frequencies at their location.Determine and provide to CBSDs235the maximum permissible transmission power level at their location.Communicate with the ESC220to obtain information about federal Incumbent User transmissions and instruct CBSDs to move to another frequency range or cease transmissions.Ensure that CBSDs235operate in geographic areas and within the maximum power levels required to protect federal Incumbent Users from harmful interference.Register and authenticate the identification information and location of CBSDs235.Ensure that CBSDs235protect non-federal Incumbent Users from harmful interference.Protect Priority Access Licensees from interference caused by other PALs and from General Authorized Access Users.Facilitate coordination between GAA users operating Category B CBSDs.Resolve conflicting uses of the band while maintaining, as much as possible, a stable radio frequency environment.Ensure secure and reliable transmission of information between the SAS and CBSDs.Protect Grandfathered Wireless Broadband Licensees.Implement the terms of current and future international agreements as they relate to the Citizens Broadband Radio Service.

The ESC220monitors for incumbent radar activity in coastal areas and near inland military bases. For example, the ESC220can employ spectrum sensing technologies in conjunction with the SAS, in order to allow CBRS users to operate near coastlines on frequencies not being used by the federal radar systems. When incumbent activity is detected, the ESC220communicates that information to SAS1. The SAS or SASs will reconfigure local devices within 300 s to avoid interfering with the detected incumbent radars, for example.

The FCC databases215include information related to commercial users and corresponding licenses (e.g., site-based licensing information). SAS1205and SAS2210are capable of directly interfacing with the FCC databases215to access information used for SAS operations.

The Domain Proxy230is a managing intermediary. A Domain Proxy's function is to, for example:Accept a set of one or more available channels and select channels for use by specific CBSDs, or alternatively pass the available channels to the carrier EMS240for CBSD channel selection;EMS240may optionally be co-located with the domain proxy230;Back report selected channels to SAS optionally received via EMS240;Receives confirmation of channel assignment from SAS;forms bidirectional bulk CBSD registration and directive processing, optionally through carrier EMS if present;Perform bidirectional information processing and routing;E.g. interference reporting, etc.

As mentioned above, a SAS can compute, for example every day, a channel allocation/assignment to be provided to the CBSDs. For the next day, the SAS can re-evaluate the channel assignment. In order to determine the channel assignment, an objective function is used to compare different channel assignments so that the determined channel allocation/assignment is the best among all the different possible channel assignments. To do so, the objective function is based on a bandwidth (BD) and a power level (PL), for example the objective function (OF) can be given by: OF=BD×PL. As such, the more bandwidth and power level a channel assignment has, the more valuable (better) this channel assignment is.

However, such an objective function does not take into account other important aspects of channel assignments. Embodiments of the present disclosure provide a method for determining a channel assignment, which takes into consideration different aspects such as:

1) Maximizing Channel Usability:

This aspect allows to assign channels in a way that will allow CBSDs235to operate close to the desired power level. In some cases, even though a channel can provide a good output power, some CBSDs, which are in proximity to incumbents (e.g. radar systems or satellite systems) need to reduce their power. Therefore, the channel is not fully usable by the CBSDs. By maximizing the channel usability, the right channel can be allocated to such CBSDs.

2) Contiguous Channel Assignment or Proximal Spectrum Allocation to Meet CBSD Instantaneous BandWidth (IBW) Constraints:

This aspect allows to assign channels that are close to each other to fit within the CBSD IBW. This aspect is important because radio operators' equipment do not have the entire band/spectrum but only a limited IBW to operate. For example, an operator can have equipment (CBSDs) with 60 MHz as its IBW. If it receives a channel outside of this IBW, it cannot use it even though it wants to. Therefore, it is important to receive channel assignments that are contiguous within the IBW.

3) Long Term Spectrum Allocation Stability:

This aspect allows operators to be assigned the same channel over a period of time, instead of changing channel assignment each day for example.

4) Provide High User Value:

The User Value (UV) has been defined in the patent application WO2018/087663, entitled “A method and a controlling node for controlling resources in a shared channel”. The User Value allows to make sure that every user has a good Signal-to-interference-plus-noise ratio (SINR) and a good channel to use, in the context of shared spectrum scenarios. For example, the UV function can be a utility function or a metric that expresses the value provided by the CBSD to an end user device present in a certain location. For example, an average of the User Value can be computed as follows. More specifically, the estimated User Value (UV) for a CBSD x in a channel ch is computed according to the following, with reference toFIG.3.

FIG.3illustrates a coverage area300of the CBSD x, which has CBSD b and CBSD a as neighbors.

The UV is based on SINR, with

SINR=sI+N,
where S is the power of the signal of the serving CBSD, I is the power of the interference and N is the power of the noise.

The SINR can be rewritten in dB as:

SINRdB=SdB-NdB-log1⁢0⁡(1+1⁢0IdB1⁢01⁢0NdB1⁢0)

The UV can be calculated on a grid of points within the coverage300of the CBSD x. The calculation includes interference received from the neighbor CBSDs such as CBSD a and CBSD b, within a radius of 40 km from each grid point, for example, operating in the same channel as well as adjacent and alternate channels. Also, only CBSDs that are part of the same connected set are considered.

The Estimated User Value for a CBSD x in a channel ch can be calculated as an average as follows:
UV(x,ch)=Average(SINRdb(p,x,ch))where p are the grid points within the coverage of the CBSD x.
5) Fairness:

This aspect allows to assign the same amount of spectrum to the ICGs, unless overridden by agreements between ICGs, so that there is an equal share of the spectrum among the users. As such, a fairness metric can be developed and used. Other potential use of other fairness metrics can be considered as well.

Furthermore, it should be noted that other factors and considerations can be taken into account when calculating the objective function for channel assignments, as will be appreciated by a person skilled in the art.

In order to consider all the aspects and factors in the objection function, a points system or a weight system can be used and will be described now.

Let's consider CQ(x, ch) as a function that indicates the channel quality for the channel ch if it has been assigned to CBSD x.

For example, if the channel ch is 10 MHz wide, then 5 MHz channels do not get any points.

For example, the function CQ(x, ch) can be based on the following points system:

1) Based on the Desired Power:

Subtract 10*(Desired_power−IAP_power) points if [Desired_power−IAP_power<=10 dB];Subtract 500 points if [Desired_power−IAP_power>10 dB].
2) Based on Allocation Stability:Add 10 points if the channel ch was also assigned to CBSD x the day before;Add 10 points if the channel ch was also assigned to CBSD x for the last week;Add 10 points if the channel ch was also assigned to CBSD x for the last month.
3) Based on Contiguous Allocation:Add 25 points if the adjacent channel ch−1 (channel below) is also assigned to CBSD x;Add 25 points if the adjacent channel ch+1 (channel above) is also assigned to CBSD x;Subtract 25 points if the adjacent channel ch−1 is also assigned to a different CxG (Co-existence Group, which may use a different technology, for example);Subtract 25 points if the adjacent channel ch+1 is also assigned to a different CxG;
4) Based on Channel Quality (User Value):Add 100 points if estimated User Value>10 for CBSD x in channel ch;Add 50 points if estimated User Value is between 5 and 10 for CBSD x in channel ch;Add 10 points if estimated User Value>0 for CBSD x in channel ch.

It should be noted that different values for the points can be used. The above points are only examples. Furthermore, a different weight system can be used, which allows to provide more or less weights to the CQ functions depending on different conditions.

The channel quality function (CQ) can be calculated for each channel and each CBSD. Then, the overall objective function can be determined as follows.

For a channel assignment m, the new objective function used to compare the quality of channel assignments is:
OF(m)=ΣxΣchCQ(x,ch)

The goal is to maximize this Objective Function. As such, the CxMs shall select a channel assignment m that has the maximum OF(m).

Examples from simulations using the new objective function are given below.

For example, let's suppose there are 6 channels of 10 MHz that are available for CBRS-A of a CxG and 3 CBSDs are in the connected set. Each table (below) shows a particular channel assignment for the 3 CBSDs. The value given by the objection function allows to determine which channel assignment from the 3 tables is to be used, for example.

TABLE 1Simulation 1 (S1)- baselinech − 1ch + 1DesiredIAPPowerch daych weekch monthStabilitysamesameS1EIRPEIRPPointsbeforebeforebeforePointsCBSDCBSDCBSD1-ch14740−7010101030025CBSD1-ch24740−7010101030250CBSD2-ch32525010101030025CBSD2-ch42525010101030250CBSD3-ch53030010101030025CBSD3-ch63030010101030250ch − 1ch + 1ContiguousdifferentdifferentAllocationUVCostObjectiveS1CxGCxGPointsUVPointsFunctionFunctionCBSD1-ch1−25001110060640.00CBSD1-ch200251110085CBSD2-ch3002512.5100155CBSD2-ch4002512.5100155CBSD3-ch50025950105CBSD3-ch60−25095080

TABLE 2Simulation 2 (S2) - channels switched to improve power level for CBSD1ch − 1ch + 1DesiredIAPPowerch daych weekch monthStabilitysamesameS2EIRPEIRPPointsbeforebeforebeforePointsCBSDCBSDCBSD3-ch130300000000CBSD1-ch24740−7010101030250CBSD2-ch32525010101030025CBSD2-ch42525010101030250CBSD3-ch53030010101030025CBSD3-ch64745−20000000ch − 1ch + 1ContiguousdifferentdifferentAllocationUVCostObjectiveS2CxGCxGPointsUVPointsFunctionFunctionCBSD3-ch1−250−2595025580.00CBSD1-ch200251110085CBSD2-ch3002512.5100155CBSD2-ch4002512.5100155CBSD3-ch50025950105CBSD3-ch60−25−251110055

TABLE 3Simulation 3 (S3) - channels switched to improve power level for CBSD1ch − 1ch + 1DesiredIAPPowerch daych weekch monthStabilitysamesameS3EIRPEIRPPointsbeforebeforebeforePointsCBSDCBSDCBSD3-ch1303000000025CBSD3-ch2303000000250CBSD2-ch32525010101030025CBSD2-ch42525010101030250CBSD3-ch5474700000025CBSD1-ch64745−200000250ch − 1ch + 1ContiguousdifferentdifferentAllocationUVCostObjectiveS3CxGCxGPointsUVPointsFunctionFunctionCBSD3-ch1−250095050640.00CBSD3-ch2002595075CBSD2-ch3002512.5100155CBSD2-ch4002512.5100155CBSD3-ch5002511100125CBSD1-ch60−2501110080

It should be noted that in the tables 1 to 3 above, EIRP is the Effective Isotropic Radiated Power and the Cost Function is the same as the channel Quality function (CQ). IAP EIRP is the power level assigned by the SAS to the CBSD after IAP completion. IAP stands for Iterative Allocation Process, and it is done to protect incumbents and higher tier users from interference. IAP happens during CPAS (Coordinated Periodic Activities among SASs) which is a daily midnight activity when SASes exchange information and compute the power reduction required to protect incumbents.

The different tables above show different values given by the objective function (last column). The different values for the objective function can be compared and the best value can be selected. The channel assignment that produced the best value of the objective function can be given to the CBSDs.

For example, in S1 baseline, the Objective function yields 640 points. In this scenario, CBSD1 is assigned to channels ch1and ch2, CBSD2 is assigned to channels ch3and ch4and CBS3 is assigned to channels ch5and ch6.

In S2, the objective function yields 580 points, which is lower than S1; as such, the channel assignment as shown in S2 should not be used.

In S3, the objective function yields 640 points, which is equal to S1. This channel assignment can be used in order to improve the power for CBSD1. The channel assignment for S3 is as follows: CBSD1 ise assigned to channels ch5and ch6, CBSD2 isassigned to channels ch3and ch4, and CBSD3 is assigned to ch1and ch2.

Since the channel assignment of S3 has the advantage of having higher power gains for CBSD1, the controlling node (CxM or SAS) can decide to use this channel assignment instead of the channel assignment of S1. However, this means that the SAS/CxM needs to implement a change of channel assignment, by removing the existing channel assignment (from S1, for example) and assigning the different channels to the CBSDs according to the channel assignment of S3.

FIG.4illustrates some embodiments of methods in a controlling node, such as SAS1, for determining a channel assignment and transmitting it to network nodes, in accordance with a first aspect of the present disclosure.

Some embodiments of the method400according to this aspect comprise the following steps:Step410(optional): receiving a request from a network node for a grant of resources (or a channel) in a shared spectrum;Step420: determining a channel assignment, based at least on a factor, the factor including one or more of channel usability, contiguous spectrum allocation, spectrum allocation stability and user value;Step430: transmitting the determined channel assignment to a network node.

The network node is for example a CBSD235.

In some embodiments, step420is performed in response to receiving a request for resources or channel from a network node. In some other embodiments, step420is performed by the SAS1205without receiving a request for resources from a network node. Indeed, the SAS1205can determine the channel assignment as a predefined activity, every day, for example.

In step420, the channel assignment is determined as explained above, using the new objective function, which takes into account different aspects/factors such as channel usability, contiguous spectrum allocation, spectrum allocation stability, user value and fairness.

In some embodiments, the factor further comprises a fairness metric.

In some embodiments, the determined channel assignment is given by optimizing an objective function.

In some embodiments, the objective function is based on a plurality of channel quality functions.

In some embodiments, the plurality of channel quality functions indicates a quality of a channel based on the factor, the factor including channel usability, contiguous spectrum allocation, spectrum allocation stability and user value.

In some embodiments, the plurality of channel quality functions is determined based on a points system.

In some embodiments, the new objective function comprises the sum of all the weighted quality functions or quality functions resulting from the points system. Other methods can be used to take into consideration the different factors, as well.

In some embodiments, transmitting the determined channel assignment to a network node can comprise assigning one or more channels to the network node based on the determined channel assignment.

FIG.5is a block diagram of an exemplary controlling node500, such as SAS1205, that may be used to determine a channel assignment based on the factors discussed herein. The controlling node500includes a processing circuitry510, and a network interface520. The circuitry510may include one or more (node) processors530, and memory540. In some embodiments, the one or more processors530executes the method400and all embodiments as described above. The memory540stores the instructions for execution by the one or more processors530, and the network interface520communicates signals to the other elements, such as the FCC databases, the CBSD, the ESC, the domain proxy, etc.

The one or more processors530may include any suitable combination of hardware and software implemented in one or more modules to execute instructions and manipulate data to perform some or all of the described functions of the SAS, such as those described above. In some embodiments, the one or more processors530may include, for example, one or more computers, one or more central processing units (CPUs), one or more microprocessors, one or more applications, one or more application specific integrated circuits (ASICs), one or more field programmable gate arrays (FPGAs) and/or other logic. In certain embodiments, the one or more processors530may comprise one or more of the modules discussed below with respect toFIG.6.

The memory540is generally operable to store instructions, such as a computer program, software, an application including one or more of logic, rules, algorithms, code, tables, etc. and/or other instructions capable of being executed by one or more processors530. Examples of memory540include computer memory (for example, Random Access Memory (RAM) or Read Only Memory (ROM)), mass storage media (for example, a hard disk), removable storage media (for example, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or or any other volatile or non-volatile, non-transitory computer-readable and/or computer-executable memory devices that store information.

In some embodiments, the network interface520is communicatively coupled to the one or more processors530and may refer to any suitable device operable to receive input for the controlling node500, send output from the controlling node500, perform suitable processing of the input or output or both, communicate to other devices, or any combination of the preceding. The network interface520may include appropriate hardware (e.g., port, modem, network interface card, etc.) and software, including protocol conversion and data processing capabilities, to communicate through a network.

Other embodiments of the controlling node500may include additional components beyond those shown inFIG.5that may be responsible for providing certain aspects of a SAS' functionality, including any of the functionality described above and/or any additional functionality (including any functionality necessary to support the solutions described above).

Processors, interfaces, and memory similar to those described with respect toFIG.5may be included in other network nodes. Other network nodes may optionally include or not include a wireless interface. Functionalities described could reside within the same node or could be distributed across a plurality of nodes and network nodes.

FIG.6illustrates an example of a controlling node600in accordance with another embodiment. The controlling node600could be a SAS. The controlling node600may include a receiving module610, a determining module620and a transmitting module630.

In certain embodiments, the receiving module610may perform a combination of steps that may include steps410ofFIG.4.

The determining module620may perform a combination of steps that may include steps such as Step420ofFIG.4.

In certain embodiments, the transmitting module630may perform a combination of steps that may include steps such as Step430ofFIG.4.

In certain embodiments, the receiving module610, the determining module620and the transmitting module630may be implemented using one or more processors, such as described with respect toFIG.5. The modules may be integrated or separated in any manner suitable for performing the described functionality.

It should be noted that according to some embodiments, virtualized implementations of the controlling node ofFIGS.5and6and of the CBSDs are possible. As used herein, a “virtualized” network node or controlling node (e.g., a virtualized base station or a virtualized radio access node or a SAS) is an implementation of the network node or controlling node in which at least a portion of the functionality of the network node/controlling node is implemented as a virtual component (e.g., via a virtual machine(s) or container(s) executing on a physical processing node(s) in a network(s)). As such, the functions of the controlling nodes500and600(described hereinabove) could be distributed across a cloud computing system.

Any steps or features described herein are merely illustrative of certain embodiments. It is not required that all embodiments incorporate all the steps or features disclosed nor that the steps be performed in the exact order depicted or described herein. Furthermore, some embodiments may include steps or features not illustrated or described herein, including steps inherent to one or more of the steps disclosed herein.

Any two or more embodiments described in this document may be combined in any way with each other.

Modifications, additions, or omissions may be made to the systems and apparatuses described herein without departing from the scope of the disclosure. The components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses may be performed by more, fewer, or other components. Additionally, operations of the systems and apparatuses may be performed using any suitable logic comprising software, hardware, and/or other logic. As used in this document, “each” refers to each member of a set or each member of a subset of a set.

Modifications, additions, or omissions may be made to the methods described herein without departing from the scope of the disclosure. The methods may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order. Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to “a/an/the element, apparatus, component, means, step, etc.” are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

Although this disclosure has been described in terms of certain embodiments, alterations and permutations of the embodiments will be apparent to those skilled in the art. Accordingly, the above description of the embodiments does not constrain this disclosure. Other changes, substitutions, and alterations are possible without departing from the spirit and scope of this disclosure.

Some of the abbreviations used in this disclosure include:AAS Active Antenna SystemASA Authorized Shared AccessARUV Average Relative User ValueCBRS Citizen's Broadband Radio ServiceCBSD Citizens Broadband radio Service DeviceCxM Co-existence ManagerCxG—Co-existence GroupCSI-RS Channel State Information Reference SignalESC: Environmental Sensing CapabilityeNB E-UTRAN NodeBE-UTRAN Evolved UTRANUTRAN Universal Terrestrial Radio Access NetworkGAA: General Authorized AccessIA Interference alignmentICIC Inter-cell interference coordinationICG Interference coordination groupLSA Licensed Shared AccessPAL: Priority Access LicensePPA: PAL Protection AreaRAT Radio Access TechnologyRSRP Reference Signal Received PowerRSRQ Reference Signal Received QualityRS-SINR Reference Signal SINRRUV Relative User ValueSARUV Sum of Relative Average User ValuesSAS Spectrum Access SystemSINR Signal to Interference plus Noise RatioSLNR Signal leakage-to-noise ratioUV User Value functiongNB Base station in NRNR New RadioWISPA Wireless Internet Service Provider Association