Method and apparatus for satellite-based weather detection - Patents.com

Abstract

The technique relies on the calculation of a weather metric (52) to detect weather conditions affecting a satellite coverage area (26), the weather metric (52) being based on evaluating monitored values ​​(92) of satellite link parameters in relation to a reference value (98). The reference value (98) may be understood as representing a clear sky value determined from past evaluations of historical monitoring of the satellite link parameters of the satellite coverage area (26). Having the reference value (98) based on past evaluations made for the coverage area (26) provides an advantageous relative basis for evaluating ongoing weather conditions. One application of the technique is the detection of weather-induced outages, for example to determine compliance exceptions with respect to a service level agreement (SLA) between the involved satellite service provider and subscribers covered by the SLA. Another application is to control scheduling or load balancing in the involved satellite communication system (10).

Description

[Technical field]

[0001] The technique relies on the calculation of weather metrics to detect weather conditions affecting service within a corresponding satellite service area, the weather metrics being based on evaluating monitored values ​​of satellite link parameters in relation to baseline values ​​determined from past evaluations. [Background technology]

[0002] "Rain fade" in the context of satellite communications systems refers to the signal attenuation that occurs with certain atmospheric conditions, such as rain, sleet, or snow. Rain fade can reduce throughput between the satellite and subscriber terminals located within the affected service area, or in more severe cases, can cause a service outage. Ku and Ka bands are particularly susceptible to rain fade, but the phenomenon is of concern across a range of signal frequencies.

[0003] Exemplary approaches are known for detecting weather conditions that affect satellite services. An exemplary satellite weather detection system uses atmospheric precipitation density data. For example, data such as upstream transmit power, downstream signal strength, or signal-to-noise ratio (SNR) can be collected, normalized, and compared to current atmospheric data to detect storms. See U.S. Pat. No. 8,730,086 (B2) and U.S. Pat. No. 9,091,763 (B2).

[0004] However, a need remains for techniques that provide weather metrics on an automated basis, with sufficient reliability and granularity, to apply to one or more functions of a satellite communications network. Summary of the Invention

[0005] The technique relies on the calculation of weather metrics to detect weather conditions affecting a satellite coverage area, the weather metrics being based on evaluating monitored values ​​of satellite link parameters in relation to a reference value. The reference value may be understood as representing a clear sky value determined from past evaluations of historical monitoring of the satellite link parameters of the satellite coverage area. That the reference value is based on past evaluations made for the coverage area provides an advantageous relative basis for evaluating ongoing weather conditions. One application of the technique is the detection of weather-induced outages, for example to determine compliance exceptions with respect to a Service Level Agreement (SLA) between the involved satellite service provider and subscribers covered by the SLA. Another application is controlling scheduling or load balancing in the involved satellite communication system.

[0006] One embodiment includes a method of operation by a computer system, the method including determining a weather metric for each of one or more time intervals for each of one or more service areas of a satellite communications system, for each service area and time interval, the weather metric being determined based on receiving monitored values ​​of satellite link parameters monitored for a population of subscriber terminals in the service area during the time interval, calculating an evaluation value as a function of the monitored values, and calculating a weather metric as a function of the evaluation value and as a function of a reference value determined from a plurality of past evaluation values ​​calculated for a plurality of previous time intervals for the service area.

[0007] Another embodiment comprises a computer system including an interface circuit and a processing circuit, the processing circuit operative to determine a weather metric for each of one or more time intervals for each of one or more service areas of a satellite communications system, and to calculate the weather metric for each service area and time interval, the processing circuit is configured to receive, via the interface circuit, monitored values ​​of satellite link parameters monitored for a population of subscriber terminals in the service area during the time interval, calculate an evaluation value as a function of the monitored values, and calculate the weather metric as a function of the evaluation value and as a function of a reference value determined from a plurality of past evaluation values ​​calculated for a plurality of previous time intervals for the service area.

[0008] Of course, the present invention is not limited to the above features and advantages, and in fact, those skilled in the art will recognize additional features and advantages upon reading the following detailed description, and upon viewing the accompanying drawings. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram of a satellite communications system in accordance with an exemplary embodiment. [Diagram 2] FIG. 2 is a block diagram of a computer system in accordance with an exemplary embodiment. [Figure 3A] FIG. 3A is a diagram of an example time interval structure used to calculate evaluation and reference values ​​for weather metric determination. [Figure 3B] FIG. 3B is a diagram of an exemplary time interval structure used to calculate evaluation and reference values ​​for weather metric determination. [Figure 4] FIG. 4 is a logic flow diagram of a method of operation by a computer system in accordance with an exemplary embodiment. [Diagram 5] FIG. 5 is a logic flow diagram of a method of operation by a computer system in accordance with an exemplary embodiment. [Figure 6]FIG. 6 is a plot illustrating an exemplary behavior of satellite link parameters with respect to weather for a population of subscriber terminals within the coverage area of ​​a satellite communications system. [Figure 7] FIG. 7 is a plot showing calculated weather metrics depending on the behavior of the satellite link parameters illustrated in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] 1 illustrates a satellite communications system 10, “System 10,” according to an exemplary embodiment. The calculation and use of the “Weather Metrics” disclosed herein is not limited to the particular system configuration illustrated in FIG. 1, but the figure provides useful example details for discussion.

[0011] The exemplary system 10 includes one or more terrestrial gateway terminals 12, which may be referred to as "gateway terminals," or "gateway stations," or "access nodes," or simply "gateways" for convenience. The exemplary system 10 further includes one or more satellites 14, e.g., the system 10 may include a constellation of satellites 14. Each satellite 14 includes a bus 16 that comprises the satellite 14's infrastructure, including a power system. Each satellite 14 further includes a payload 18, which is a communications package carried by the satellite 14 and includes or is associated with an antenna 20 for receiving from and transmitting to one or more respective gateways 12, and is associated with an antenna 22 for receiving from and transmitting to subscriber terminals 24 within one or more service areas 26.

[0012] The subscriber terminals 24 within a given service area 26 may be considered a constellation 28 of subscriber terminals 24. Each service area 26 may be the terrestrial footprint of an antenna beam 30 formed by a respective satellite 14 or by the system 10 as a whole. However, a service area 26 may correspond to more than one antenna beam 30, e.g., beams 30 having overlapping ground coverage areas or "footprints." Some service areas 26 may be smaller or larger than others. For example, multiple smaller service areas 26 may be used to serve geographic regions having a higher density of subscriber terminals 24, while a single larger service area 26 may be used for geographic regions having a lower density of subscriber terminals 24.

[0013] At least some of the subscriber terminals 24 may be stationary, fixed location terminals, such as those used for television or other broadband services provided via system 10. A single subscriber may own or lease multiple subscriber terminals 24 and may use one or more of the communication services provided through system 10, for example, under a service level agreement (SLA) between the operator of system 10 and the subscriber. A subscriber may be an individual or an organization, such as a company.

[0014] The payload 18 in each satellite 14 in the system 10 comprises, for example, one or more transponders. Each transponder provides a signal path through the satellite 14 and includes receiver circuitry and corresponding transmitter circuitry, for example, for relaying received signals at the same or converted frequencies. The payload 18 may include switching circuitry for selectively coupling each of the transponders with selected antenna feeds corresponding to respective coverage areas associated with the gateway 12 and the subscriber terminals 24. The transponders may be configured as non-processing signal paths, which may perform frequency translation and other signal conditioning, but relay received signals for retransmission without intervening demodulation and regeneration.

[0015] Regardless of whether the satellites 14 use unprocessed or processed signal paths, the system 10 provides a forward channel and a return channel. Between a given gateway 12 and a given satellite 14, the forward channel comprises a forward channel uplink 32 representing a wireless uplink coupling between the gateway 12 and the satellite 14, and a forward channel downlink 34 representing a wireless downlink coupling between the satellite 14 and a subscriber terminal 24 in a respective service area 26. Each satellite 14 may provide multiple forward channel downlinks 34 corresponding to a respective service area 26. Correspondingly, for each service area 26, the return channel comprises a return channel uplink 36 representing a wireless uplink coupling between the satellite 14 and a respective subscriber terminal 24 in the service area 26. The return channel further comprises a return channel downlink 38 representing a wireless downlink coupling between the satellite 14 and the gateway 12.

[0016] Along with the gateway 12, the ground segment 40 of the system 10 includes a ground segment processing system 42 that handles communication signal processing and, for example, interfaces with one or more external communication networks 44. The external network(s) may include, for example, any one or more of the Public Switched Telephone Network (PSTN), the Internet, or other Packet Data Networks (PDNs). The external communication network(s) 44 may, for example, act as a source of user traffic that is provided to each subscriber terminal 24.

[0017] The ground segment processing system 42, which may be distributed or centralized with respect to the gateway 12, includes or is associated with one or more control entities 46. The control entities 46 are configured to perform, for example, any one or more of scheduling and dynamic load balancing within the system 10. "Scheduling" refers to the scheduling of user traffic to / from each subscriber terminal according to, for example, system load and defined scheduling objectives that take into account, for example, fairness, link throughput, service prioritization, subscriber prioritization, etc. "Load balancing" refers to steering traffic flows for better bandwidth utilization across beams 30 and satellites 14.

[0018] The ground segment 40 includes or is communicatively coupled to a computer system 50, e.g., a networked server, configured to calculate weather metrics 52 for one or more service areas 26 of the system 10. For example, the computer system 50 is configured to calculate weather metrics 52 for each of the one or more service areas 26 of the system 10 on an hourly basis or according to some other recurring time interval, e.g., every 5 minutes, every 30 minutes, every 2 hours, or according to some other time granularity.

[0019] Generally speaking, computer system 50 is configured to determine weather metrics 52 for each of one or more time intervals for each of one or more service areas 26. Each time interval may include a periodically repeating time interval or any particular time interval within a contiguous succession of similar time intervals, and computer system 50 may determine weather metrics for either or both of such time interval definitions.

[0020] A periodically repeating time interval is a time slice that repeats daily, e.g., the same time each day, the same 30 minutes each day, etc. A time interval within a closely contiguous time interval is, for example, any given 5-minute window within a running contiguous 5-minute interval. Of course, the running interval may have a different granularity, such as 10 minutes, 15 minutes, etc. It should be understood that a "time interval" refers to a particular window of time, and thus the phrase "previous time interval" refers to a similar window of time that precedes the particular time window in question. Thus, if an exemplary time interval is any given 5-minute window, the multiple time intervals "previous" to the given 5-minute window may be a close succession of previous 5-minute windows, or a set of 5-minute windows that occur at the same time over the last few days. The computer system 50 in one or more embodiments may calculate weather metrics 52 based on an understanding of either or both of "time interval" and "previous time interval."

[0021] In one or more embodiments, the computer system 50 is configured to output the weather metric information as a signaling 54 to a database 56. The database 56 may be local to the computer system 50 or, in the illustrated example, may be remote to the computer system 50, for example, hosted in a remote business support system (BSS) 58. The BSS 58 may be another networked server. The weather metric information may include, for example, one or more weather metrics 52 calculated by the computer system 50, or a corresponding evaluation result. For example, evaluating a particular weather metric 52 calculated for a particular service area 26 and for a particular time interval may include determining whether a value of the weather metric 52 indicates the presence of weather. More specifically, the evaluation in one or more embodiments may include determining whether the weather metric 52 indicates a service failure based, for example, on a value of the weather metric 52 being below (or above) a defined threshold corresponding to a substantial service failure.

[0022] In one or more embodiments, computer system 50 receives signaling 60 originating from ground segment 40, conveying, for example, monitored values ​​of satellite link parameters for each constellation 28 of subscriber terminals 24 within a corresponding service area 26 of system 10. Here, any number of measurements or indicators of link quality between satellite 14 and each subscriber terminal 24 in constellation 28 may serve as the satellite link parameters used in the calculation of weather metric 52. Example parameters include the transmit power of the subscriber terminal, the received signal SINR at the subscriber terminal 24, or the received signal SINR at the satellite 14 for the subscriber terminal 24.

[0023] Another example parameter is the "Home Channel Symbol Rate" or HCSR. Exemplary details of HCSR are described in U.S. Pat. No. 8,547,863 (B2). Each subscriber terminal 24 may be assigned a "home channel" where the effective isotropic radiated power (EIRP) or other parameters of the subscriber terminal 24 are adjusted based on the measured signal quality on the home channel. Here, the home channel includes a particular physical channel or carrier using the highest symbol rate that the subscriber terminal 24 can operate on, subject to limitations such as error rate.

[0024] The system 10 in one or more embodiments assigns the subscriber terminals 24 to home channels that use the highest symbol rate possible. As described in U.S. Pat. No. 8,547,863 (B2), the system 10 may power control individual subscriber terminals 24 to compensate for rain fades. However, as the severity of the rain fade increases, the system 10 must begin reducing the HCSR of the affected subscriber terminals 24. Thus, the HCSR values ​​monitored for a population 28 of subscriber terminals 24 provide a good indication of the weather conditions in the corresponding service area 26.

[0025] In at least one embodiment herein, the computer system 50 implements an advantageous technique for using the monitored HCSR values ​​or monitored values ​​of another satellite link parameter reflecting link adaptations made to compensate for rain fade to calculate and evaluate weather metrics 52. Through the use of "evaluated" and "reference" values ​​described below, the weather metric technique disclosed herein presents a particularly reliable and automated mechanism for detecting and responding to weather disturbances affecting one or more service areas 26 of the system 10.

[0026] In one or more embodiments, the computer system 50 is configured to output signaling 62 including control information for controlling operation of the system 10. For example, the signaling 62 may indicate weather metrics 52 currently applicable to each service area 26 of the system 10 for use in load balancing or scheduling by the control entity 46 of the ground segment 40. The signaling 62 in at least one embodiment includes commands for one or both of load balancing and scheduling, for example, specifying particular load balancing or scheduling actions or strategies to be taken by the control entity 46 in the ground segment 40.

[0027] Additionally or alternatively, computer system 50 is configured to output signaling 63, including a notification, which may be an alarm. The notification, including signaling 63, may be sent to BSS 58 or may be transmitted to other computer systems or devices associated with system 10, such as computer systems or devices used by an operator of system 10 to monitor the health and operation of system 10.

[0028] 2 illustrates exemplary details of a computer system 50 according to one or more embodiments, where the computer system 50 includes a processing circuit 70 and associated storage 72, including one or more types of computer readable media, such as SRAM or DRAM or other volatile storage, and a hard drive or solid state disk (SSD) for non-volatile storage. The storage 72 holds, for example, one or more computer programs 74, shown in the figure as "CP(s)," and may also hold one or more types of data 76. In at least one embodiment, the processing circuit 70 includes one or more microprocessors specially adapted to perform the weather metric processing described herein based on the execution of computer program instructions stored in the storage 72 as the one or more computer programs 74.

[0029] Further exemplary elements of computer system 50 include communications circuitry 80 and input / output (I / O) circuitry 82, either or both of which may be referred to as "interface circuitry" to indicate their role in providing a communications coupling between computer system 50 and one or more external devices or systems. As an example, communications circuitry 80 includes an Ethernet interface or other data networking interface, communicatively coupling computer system 50 to ground segment processing system 42, for example, to receive signaling 60 and send signaling 62. Communications circuitry 80 in one or more embodiments also provides a communications coupling with BSS 58. Alternatively, one or both of signaling 60 and 62 are provided via I / O circuitry 82, including, for example, interfacing with local input / output devices. I / O circuitry 82 supports interfacing with local or remote video displays, keyboards, storage systems, and the like, for operating, for example, monitoring, data recording, and the like.

[0030] In at least one embodiment, the data 76 maintained in the storage device 72 includes one or more sets 90 of monitored values ​​92, where the monitored values ​​92 are monitored values ​​of satellite link parameters, such as SINR, transmit power, HCSR, etc., corresponding to subscriber terminals 24 in one or more constellations 28. Each constellation 28 may be understood to correspond to a particular service area 26 of the system 10. Thus, a "set" 90 of monitored values ​​92 refers to monitored values ​​92 collected for a particular constellation 28, for a particular time period, i.e., a particular time of day, or some other defined time interval. Thus, there may be multiple sets 90 of monitored values ​​92 for each service area 26 of interest, with each such set corresponding to a respective time interval.

[0031] The computer system 50 processes each such set 90 of monitored values ​​92 to obtain a corresponding evaluation value 94 that is used in the calculation of the weather metric 52 for the corresponding service area 26 and time interval. The evaluation value 94 for a set 90 of monitored values ​​92 may be calculated, for example, as an average or some other statistical measure. The computer system 50 need not maintain a given set 90 of monitored values ​​92 after the corresponding evaluation value 94 has been determined.

[0032] The data 76 in one or more embodiments further includes a set 96 of metric values ​​98. For example, for each service area 26, there is a particular metric value 98 for each time interval. The metric value 98 for a particular time interval and for a particular service area 26 may be understood as a "clear weather" value for that service area 26 and that particular time interval. That is, the metric value 98 is a value that reflects the historical performance of a population 28 of subscriber terminals 24 within that service area 26 in the absence of weather disturbances. Here, the term "population" should be understood to accommodate changes in membership over time, i.e., a given population 28 does not necessarily have the same membership at all times.

[0033] Generally, a constellation 28 represents a collection of subscriber terminals 24 for a given time interval associated with a respective service area 26. In one or more embodiments, the computer system 50 is configured to ignore a constellation 28 of subscriber terminals 24 that are below or above a certain constellation size threshold. Ignoring a constellation 28 of subscriber terminals 24 means not calculating weather metrics 52 for that constellation 28.

[0034] 3A illustrates an exemplary time interval 100 that repeats periodically, e.g., hourly or daily. While the illustrated occurrences of the time interval 100 are labeled "TI1," "TI2," and "TI3," it should be understood that this figure shows only a small snapshot of a running timeline. To calculate the weather metric 52 for a given time interval TI_N for a given service area 26, designated in the figure as "SA_X," the computer system 50 uses a reference value 94 calculated from monitored values ​​92 obtained from the subscriber terminal 24 during all or a portion of TI_N, and a reference value 98 for SA_X that is dependent on the reference value 94 calculated for each previous time interval within a plurality of previous time intervals.

[0035] In this example, the previous occurrences of the time interval 100 considered are the previous occurrences TI_N-1 to TI_N-R. For example, if the time interval 100 is a particular time of day, then R represents the number of previous days considered for the calculation of the reference value 98. For any given service area 26 and for any given time interval 100, the evaluation value 94 depends on the monitored values ​​92 corresponding to the given time interval 100, and the reference value 98 depends on several reference values ​​94 calculated for multiple previous time intervals 100 for the same service area 26.

[0036] 3B shows time intervals 100 occurring consecutively, i.e., in a running series of adjacent similar intervals, such as 5-minute intervals, 10-minute intervals, or intervals of some other granularity. The calculation of the weather metric 52 for any given one of the time intervals 100 for any given service area 26, e.g., SA_X, depends on a reference value 94 determined from monitored values ​​92 obtained for all or part of the time interval 100 for a subscriber terminal 24 in SA_X, and a reference value 98 based on several reference values ​​94 calculated for a number of previous time intervals 100 for the same service area 26. In comparison with FIG. 3A, the previous time interval 100 can be taken as the R most recent consecutive time intervals 100 in the running series of time intervals.

[0037] The computer system 50 may calculate the weather metrics 52 according to the time interval structure of Figure 3A or 3B, or may calculate separate weather metrics 52 for each criterion. Broadly speaking, with either time interval structure, the weather metrics 52 calculated for a particular service area 26 and for a particular time interval 100 are based on (1) the evaluation values ​​94 calculated for the particular service area 26 and the particular time interval 100, and (2) the criterion values ​​98 calculated for the particular service area 26 and for some prior time intervals 100. These prior time intervals 100 are "similar" to the particular time interval 100 in question, at least because they are of the same duration, and, as seen in Figure 3A, they may correspond to past instances of the same time.

[0038] 3A and 3B in mind, a computer system 50 according to one or more embodiments includes an interface circuit 80 or 82 and a processing circuit 70. Here, and elsewhere in this disclosure, unless specifically stated otherwise or clear from the context, "A or B" means A alone, B alone, or both A and B. The processing circuit 70 operates to determine a weather metric 52 for each of one or more service areas 26 of the satellite communications system 10 and for each of one or more time intervals 100.

[0039] To calculate the weather metric 52 for any particular time interval 100 for any particular service area 26, the processing circuit 70 is configured to (a) receive, via the interface circuit system 80 or 82, monitored values ​​92 of satellite link parameters monitored for the time interval 100 for the population 28 of subscriber terminals 24 within the service area 26, (b) calculate an evaluation value 94 as a function of the monitored values ​​92, and (c) calculate the weather metric 52 as a function of the evaluation value 94 and as a function of a reference value 98 determined from a plurality of past evaluation values ​​94 calculated for a plurality of previous time intervals 100 for the service area 26.

[0040] Weather metrics 52 are numerical values ​​that are calculated for a particular time interval 100 and service area 26 based on applicable rating values ​​94 and applicable criteria values ​​98. "Applicable" means that the values ​​are relevant to the particular time interval 100 and the particular service area 26. Weather metrics 52 calculated in this manner indicate the presence, absence, or severity of weather outages in the service area 26 for the time interval 100. For example, the weather metric calculation may result in a numerical value that falls within a defined range, with one end of the range corresponding to no weather outages and the other end of the range corresponding to a "worst" weather outage.

[0041] Each time interval 100 includes any particular time interval within a periodically repeating time interval or a contiguous succession of like time intervals. In one example, the time interval of interest 100 is a time of day such that the weather metric 52 calculated for any given time on a particular day for any given service area 26 depends on the rating value 94 calculated for that given time on that particular day, and such that the applicable criteria value 98 depends on the rating value 94 calculated for several previous occurrences of that time for the given service area 26, for example over the past month.

[0042] In one or more embodiments, the processing circuitry 70 is further configured to output signaling 54 to the database 56 via the interface circuitry 80 or 82. The signaling 54 indicates one or more weather metrics 52 calculated by the processing circuitry 70, or corresponding evaluation results, along with a time stamp and coverage area information.

[0043] The processing circuitry 70 in one or more embodiments is further configured to output signaling 62 via an interface circuitry 80 or 82 to a control entity 46 in the ground segment 40 of the satellite communications system 10. The signaling 62 is indicative of one or more weather metrics 52 or corresponding evaluation results, and the control entity 46 operates in dependence on the signaling 62 to implement at least one of load balancing and transmission scheduling in the satellite communications system 10.

[0044] In one or more embodiments, the processing circuitry 70 is further configured to output signaling 63 including one or more notifications via the interface circuitry 80 or 82 in response to at least certain values ​​of the one or more weather metrics 52. For example, the processing circuitry 70 outputs or controls the computer system 50 to initiate the output of one or more types of electronic signals in response to detecting that the one or more weather metrics 52 are below (or above) a threshold associated with a significant weather disturbance. Examples of electronic signals include a Short Messaging Service (SMS) message, an email, or a signal for a computer display, an audible annunciator, a visual annunciator, etc.

[0045] According to at least one embodiment, the criterion value 98 for each service area 26 and each time interval 100 is a numerical value having a percentile rank defined for the service area 26 with respect to a corresponding plurality of past rating values ​​94 calculated with respect to a corresponding plurality of previous time intervals 100, where the corresponding plurality of past rating values ​​94 and the corresponding plurality of previous time intervals 100 are “applicable” rating values ​​94 and previous time intervals 100 within the meaning described above.

[0046] In one or more embodiments, the satellite link parameter is an adaptive home channel symbol rate (HCSR). In such an embodiment, for each service area (26) and each time interval (100), the monitored value 92 is the HCSR of each of the subscriber terminals 24 in the service area 26 during all or a portion of the time interval 100. In at least one such embodiment, the estimated value 94 for each service area 26 and time interval 100 is calculated as a weighted average of the HCSRs in use by a respective number of subscriber terminals 24 operating within the service area 26.

[0047] In one or more embodiments, the processing circuitry 70 is further configured to correlate a service outage event detected for any particular service area 26 with an indication of weather disruption for the particular service area 26, as indicated by a corresponding weather metric 52 calculated for the particular service area 26.

[0048] The satellite communications system 10 may, for example, include a plurality of service areas 26, and the processing circuitry 70 in one or more embodiments may be configured to not calculate weather metrics 52 for service areas 26 below a particular service area size threshold or not calculate weather metrics 52 for service areas 26 above a particular service area size threshold. Additionally or alternatively, the processing circuitry 70 may be configured to not calculate weather metrics 52 for service areas 26 having a population 28 of subscriber terminals 24 below a particular population size threshold. Additionally or alternatively, the processing circuitry 70 may be configured to not calculate weather metrics 52 for service areas 26 having more than a threshold percentage of offline subscriber terminals 24. Further, in one or more embodiments, the processing circuitry 70 may be configured to exclude certain subscriber terminals 24 within a population 28 of subscriber terminals 24 from consideration in the calculation of the rating value 94.

[0049] In at least one embodiment, the weather metric 52 is calculated as a numerical value within a range bounded by a range minimum and a range maximum, where one of the range minimum or range maximum corresponds to no weather effect and the other of the range minimum or range maximum corresponds to maximum weather effect. In certain embodiments, the weather metric 52 has a maximum value corresponding to an absence of weather disturbance and a lower threshold value corresponding to maximum weather disturbance, below which values ​​are considered invalid as resulting from faulty or insufficient input data, e.g., monitored values ​​92 from a population 28 of subscriber terminals 24.

[0050] In a more detailed example, a given time interval 100 of interest is repeated on a daily basis. For a particular service area 26, the processing circuitry 70 is configured to maintain the reference value 98 for the time interval 100 as a value having a percentile ranking defined for the service area 26 relative to the plurality of past evaluation values ​​94 calculated for previous occurrences of the time interval 100 over a defined number of recent days. For example, the processing circuitry 70 calculates the reference value 98 as a "p99" value relative to a running plurality of past evaluation values ​​94 determined for a corresponding plurality of past occurrences of the time interval 100. The "p99" value is the 99th percentile value, meaning better than 99 percent of the plurality of reference values ​​94.

[0051] Other percentile rankings or other ranking schemes may be used to arrive at the reference value 98 used to calculate the weather metrics 52 for a particular time interval 100 for a particular service area 26. For example, the reference value may be a maximum value or may be selected according to another metric. Furthermore, it should be understood that for any given service area 26, the reference value 98 for one time interval 100, e.g., 6-7 a.m. interval, may be different than the reference value 98 calculated for a different time interval 100, e.g., 3-4 p.m. interval. A further point to recognize is that the computer system 50 may calculate the weather metrics 52 for different time granularities, e.g., the computer system 50 may maintain weather metrics 52 referenced to hourly intervals, but may also maintain weather metrics 52 referenced to shorter or longer intervals, such as 10-minute or 5-minute intervals.

[0052] In one or more embodiments, the satellite link parameter whose monitored value 92 is provided for weather metric calculation is an adaptive home channel symbol rate (HCSR). In such a case, the monitored value 92 of the satellite link parameter is the HCSR for each of the subscriber terminals 24 in the service area 26 during all or a portion of the time interval 100 of interest. The HCSR is "adaptive" in the sense that the system 10 controls the HCSR for each subscriber terminal 24, e.g., sets the HCSR to the highest achievable rate for the radio conditions of each subscriber terminal 24. The system 10 may operate with a limited set of possible HCSRs, such that each subscriber terminal 24 during normal operation is the highest of those possible HCSRs that it can support given the radio conditions.

[0053] The processing circuitry 70 in at least one such embodiment is configured to calculate the evaluation value 94 as a weighted average of the HCSRs for a given time interval 100 and for a given service area 26. The weighting depends on the number of respective subscriber terminals 24 in the population 28 that operate with respective HCSRs in the set of defined HCSRs. That is, for a limited number of defined HCSRs, there may be some subscriber terminals 24 in the population 28 that operate with a first HCSR of the defined HCSRs and another number of subscriber terminals 24 in the population that operate with a second HCSR of the defined HCSRs. Thus, determining the average of the first and second HCSRs will depend on the relative numbers of subscriber terminals 24 in the population 28 that are using the first and second HCSRs.

[0054] 4 illustrates a method 400 of operation by a computer system, such as computer system 50. Method 400 includes determining a weather metric 52 for each of one or more service areas 26 of satellite communications system 10 for each of one or more time intervals 100. For each service area 26 and time interval 100, weather metric 52 is determined based on (a) receiving monitored values ​​92 of satellite link parameters monitored for the time interval 100 for a population 28 of subscriber terminals 24 within the service area 26 (block 402), (b) calculating an evaluation value 94 for the service area 26 as a function of the monitored values ​​92 (block 404), and (c) calculating weather metric 52 as a function of evaluation values ​​94 and as a function of a reference value 98 determined for the service area 26 from a plurality of past evaluation values ​​94 calculated for a plurality of previous time intervals 100 (block 406).

[0055] In one or more embodiments, the method 400 further includes (d) outputting signaling indicative of one or more weather metrics 52 or a corresponding evaluation result (block 408). One example of such signaling includes, for example, outputting signaling 54 to the BSS 58 for recording the weather metrics 52 or a result of evaluating the weather metrics 52 in a database 56. Other examples include outputting signaling 62 to one or more control entities 46 in the ground segment 40 of the system 10, for example, to control load balancing or scheduling in the system 10 in response to the detected weather disturbance, or outputting signaling 63 including a notice or alarm, for example, to alert a system operator or other responsible party of the detected weather disturbance.

[0056] Thus, block 408 may be understood as any one or more of the following: - outputting a signaling 54 indicating at least one of the weather metrics or a result of evaluating the weather metrics to a database 56 together with a time stamp and coverage area information; - outputting a signaling 62 to a control entity 46 in the ground segment 40 of the system 10, the signaling 62 indicating at least one of the weather metrics or a result of evaluating the weather metrics, the control entity 46 being operable to perform at least one of load balancing and transmission scheduling in the satellite communication system depending on the signaling, or - outputting notification signaling responsive to at least certain values ​​of weather metrics.

[0057] The method 400 may be performed for each of one or more service areas 26 of the system 10 and for each of one or more time intervals 100. When multiple service areas 26 are considered, the method 400 may be performed in parallel for the multiple service areas 26 or may be performed sequentially, one service area 26 at a time. Furthermore, the method 400 may be invoked in response to the passage of each time interval 100, for example, at the end of each time. However, the method 400 may be applied retroactively, so long as the necessary data is stored. Consider an example in which the computer system 50 or another computer associated with the system 10 maintains a historical set 90 of monitored values ​​92 or maintains a historical set of evaluation values ​​94 derived from such set 90 of monitored values ​​92. The computer system 50 may then calculate the weather metric 52 for any past time interval 100 for the service area 26 of interest, if there is sufficient stored data to determine the evaluation value 94 and the reference value 98 for that time interval.

[0058] 5 illustrates a method 500 of operation by a computer system, which may be understood to provide exemplary details for the implementation of method 400. The illustrated process is applied for each of one or more service areas 26 and for each of one or more time intervals 100.

[0059] The process "starts" with a selected time interval 100 and a selected service area 26 and involves calculating and recording weather metrics 52 for the selected time interval 100 for the selected service area 26. If there are additional service areas 26 for which weather metrics 52 for the currently selected time interval 100 are to be calculated, the process continues by selecting the next service area 26 and calculating the corresponding weather metrics 52. Such operations are repeated for the currently selected time interval 100 for all service areas 26 to be evaluated. See blocks 502, 504, and 506. The entire process is then repeated for each additional time interval 100 to be considered. See blocks 508 and 510. Thus, performing the process of FIG. 5 for multiple time intervals 100 and multiple service areas 26 will yield respective weather metrics 52 for each time interval 100 for each service area 26.

[0060] The use of weather metrics 52 as described above represents a meaningful improvement in the functionality of the satellite communications system 10. For example, satellite communications system operators, i.e., service providers, often provide services to subscribers according to negotiated parameters regarding such things as uptime, throughput, and other quality of service (QoS) metrics. These service level agreements (SLAs) often specify monetary or other penalties if the service provider fails to meet the provisions specified in the SLA. However, such agreements often have exceptions for service issues related to adverse weather.

[0061] In at least one embodiment, the computer system 50 is configured to correlate service disruptions, e.g., service outages, experienced in any given service area 26 of the system 10 with detected weather events, i.e., those detected from applicable weather metrics 52 calculated for the given service area 26. Here, "correlation" refers to determining whether a service disruption experienced in a particular service area 26 during a particular time interval 100 matches weather metrics 52 indicative of the presence of a weather disruption, calculated for that service area 26 for that time interval 100.

[0062] Among the several advantages of the weather metric calculation(s) disclosed herein is that the technique provides a simple single metric related to the impact of weather on a user beam or service area, where "related to" may be understood to mean that the calculated value of the weather metric 52 is at least somewhat proportional to the severity of the weather. Another advantage is that the weather metric 52 is not based on a count of subscriber terminals 24 within the service area 26, and may in fact be used to account for a decrease in the count of online subscriber terminals 24 within the service area 26. Another noteworthy point is that the weather metric 52 reflects the weather conditions that actually affect satellite service.

[0063] In one or more exemplary embodiments, weather metric 52 is calculated as a value between 0 and 100, with 100 representing no weather impact and the lowest value representing severe weather impact. Exemplary ranges are as follows: -95~100: No bad weather -90~95: Possible bad weather Below -90: Bad weather -0: Invalid data, ignore weather metrics.

[0064] In one or more embodiments, the weather metric 52 calculated for a given time interval 100 for a given service area 26 is based on the subscriber terminal distribution across the different return link HCSRs, where return link or "RL" refers to the uplink from the subscriber terminal 24 to the satellite 14. For example, if the time interval 100 is the time of day, then the weather metric 52 for a particular time of day for a particular service area 26 is calculated as follows: -For a particular service area26, the weighted average of the HCSR for the past 5 minutes multiplied by 100 and divided by the p99 HCSR for the previous 30 days for the same hour on that day. In the illustrative example, the highest possible HCSR is 160 and the lowest possible HCSR is 3. With these values, the weather metric 52 will not fall below a value of 3 unless the data used to calculate the weather metric 52 is invalid. If the previous week's p99 HCSR was 160 and the current HCSR is 3, then the weather metric 52 will depend on the fraction 3 / 160, which is approximately 3%, leading to the weather metric 52 having a value of 3.

[0065] The weighted average of the HCSR for the past 5 minutes may be considered an example of the rating value 94 discussed above, and the p99 HCSR may be considered an example of the reference value 98 discussed above. In particular, the p99 HCSR may be considered a clear-sky value given that it is close to the maximum weighted average HCSR observed in the same time interval for a particular service area 26 over the past 30 days. The weighted average of the HCSR for subscriber terminals 24 in a population 28 within a service area 26 may be calculated based on how many subscriber terminals 24 in the population are at each HCSR in a defined set of possible HCSRs.

[0066] In at least one embodiment, the calculation of weather metrics 52 for a given service area 26 and for a particular time interval 100 does not take into account all subscriber terminals 24 that are within the service area 26. That is, the population 28 of subscriber terminals 24 considered for the weather metric calculation may be a "filtered" population determined from a larger population in which some subscriber terminals 24 are excluded from consideration. For example, subscriber terminals 24 newly entering the population 28 may be excluded because they may not have their optimized or stabilized HCSR. Similarly, subscriber terminals 24 that are performing "ranging" or other operations may be excluded from consideration for the calculation of weather metrics 52.

[0067] Other filtering may be performed at the service area level. For example, weather metric 52 may not be calculated for a given time interval 100 for a particular service area 26 if the number of subscriber terminals 24 that were online during that time interval 100 was less than the number of "normal" subscriber terminals 24 or a portion of the expected number. Such filtering may be based on subscriber profiles or historical monitoring that provide a basis for knowing or estimating the expected number of online subscriber terminals 24. As an example, if the number of subscriber terminals 24 is less than 80 percent of the expected number for any given time interval 100 for any given service area 26, weather metric 52 is not calculated.

[0068] Figure 6 illustrates an exemplary behavior of HCSR as an exemplary satellite link parameter for a population 28 of subscriber terminals 24 in a given service area 26, e.g., a weighted average of HCSR per terminal. Figure 7 illustrates a corresponding exemplary behavior of a weather metric 52 calculated for the entire population 28 of subscriber terminals 24 in a service area 26. A weather threshold indicating significant weather is set at a 90% level, and the weather metric 52, also referred to as the weather score, remains above that level unless significant weather affects the service area 26. Of course, the numerical values ​​and the illustrated score behavior should be understood as examples applicable to the illustrated context.

[0069] In particular, modifications and other embodiments of the disclosed invention(s) will come to mind to one skilled in the art to which these disclosures pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. It is therefore to be understood that the invention(s) is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of this disclosure. Although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A method (400) of operation by a computer system (50), said method (400) comprising: determining a weather metric (52) for each of one or more service areas (26) of the satellite communication system (10) and for each of one or more time intervals (100), wherein for each service area (26) and time interval (100), the weather metric (52) is determined as follows: receiving (402) monitored values ​​(92) of satellite link parameters monitored for a population (28) of subscriber terminals (24) within said service area (26) during said time interval (100); Calculating (404) an evaluation value (94) as a function of the monitored values ​​(92); and calculating (406) the weather metric (52) as a function of the rating value (94) and as a function of a reference value (98) determined from a plurality of past rating values ​​(94) calculated for a plurality of previous time intervals (100) for the service area (26).

2. Each time interval (100) a periodically repeating time interval, or 2. The method of claim 1, including one of any particular time interval within a contiguous series of like time intervals.

3. 3. The method (400) of claim 1 or 2, further comprising outputting (408) one or more of the weather metrics (52) or a signaling (54) indicative of a corresponding evaluation result to a database (56) along with a time stamp and service area information.

4. The method (400) of any one of claims 1 to 3, further comprising outputting signaling (62) to a control entity (46) of the satellite communication system (10), the signaling (62) indicating the one or more weather metrics (52) or corresponding evaluation results thereof, the control entity (46) operating in dependence on the signaling (62) to perform at least one of load balancing and transmission scheduling in the satellite communication system (10).

5. The method (400) of any one of claims 1 to 4, further comprising outputting signaling (63) comprising one or more notifications at least in response to certain values ​​of the one or more weather metrics (52).

6. The method (400) of any one of claims 1 to 5, wherein the plurality of past rating values ​​(94) calculated for the plurality of previous time intervals (100) for a particular service area (26) comprises a running set of past rating values ​​(94) corresponding to a running window of previous time intervals (100).

7. The method (400) of any one of claims 1 to 6, wherein the criterion value (98) for each service area (26) and each time interval (100) is a numerical value having a percentile ranking defined for the service area (26) with respect to a corresponding number of past evaluation values ​​(94) calculated for a corresponding number of previous time intervals (100).

8. 8. A method (400) according to any one of claims 1 to 7, wherein the satellite link parameter is an adaptive home channel symbol rate (HCSR), and for each service area (26) and each time interval (100), the monitored value (92) is the HCSR for each of the subscriber terminals (24) within the service area (26) during all or a portion of the time interval (100).

9. 9. The method (400) of claim 8, wherein the rating value (94) for each service area (26) and each time interval (100) is calculated as a weighted average of the HCSRs in use by a respective number of subscriber terminals (24) operating within the service area (26).

10. The method (400) of any one of claims 1 to 9, further comprising correlating a service outage event detected for any particular service area (26) with an indication of weather disruption for the particular service area (26) as indicated by a corresponding weather metric (52) calculated for the particular service area (26).

11. The satellite communication system (10) includes a plurality of service areas (10), and the method (400) comprises: not calculating weather metrics (52) for service areas (26) below a certain service area size threshold; or The method (400) of any one of claims 1 to 10, further comprising at least one of not calculating weather metrics (52) for service areas (26) above a certain service area size threshold.

12. The method (400) of any one of claims 1 to 11, wherein the satellite communications system (10) includes a plurality of service areas (10), and the method (400) further comprises not calculating weather metrics (52) for service areas (26) having a population (28) of subscriber terminals (24) below a certain population size threshold.

13. The method (400) of any one of claims 1 to 12, further comprising excluding from consideration, in calculating an evaluation value (94) for any particular time interval (100) for any particular service area (26), a subscriber terminal (24) that is newly entering the satellite communication system (10) within the particular service area (26).

14. 15. A method (400) according to any one of claims 1 to 14, wherein each weather metric (52) is calculated as a numerical value within a range bounded by a range minimum and a range maximum, one of the range minimum or range maximum corresponding to no weather impact and the other of the range minimum or range maximum corresponding to maximum weather impact.

15. A computer system (50), An interface circuit (80, 82); and processing circuitry (70) operative to determine a weather metric (52) for each of one or more service areas (26) of the satellite communications system (10) and for each of one or more time intervals (100), wherein to calculate the weather metric (52) for each service area (26) and time interval (100), the processing circuitry comprises: receiving, via said interface circuitry (80, 82), monitored values ​​(92) of satellite link parameters monitored for a population (28) of subscriber terminals (24) within said service area (26) during said time interval (100); Calculating an evaluation value (94) as a function of said monitored values ​​(92); a computer system (50) configured to calculate the weather metric (52) as a function of the rating value (94) and as a function of a reference value (98) determined from a plurality of past rating values ​​(94) calculated for a plurality of previous time intervals (100) for the service area (26).

16. Each time interval (100) a periodically repeating time interval, or 16. The computer system (50) of claim 15, including one of any particular time interval within a contiguous series of like time intervals.

17. 17. The computer system (50) of claim 15 or 16, wherein the processing circuit (70) is further configured to output signaling (54) via the interface circuit (80, 82) to a database (56), the signaling (54) indicating one or more of the weather metrics (52) or corresponding evaluation results together with a time stamp and service area information.

18. 18. The computer system (50) of claim 15, wherein the processing circuit (70) is further configured to output signaling (62) via the interface circuit (80, 82) to a control entity (46) in a ground segment (40) of the satellite communication system (10), the signaling (62) being indicative of the one or more weather metrics (52) or corresponding evaluation results thereof, and the control entity (46) is operative to perform at least one of load balancing and transmission scheduling in the satellite communication system (10) in dependence on the signaling (62).

19. The computer system (50) of any one of claims 15 to 18, wherein the processing circuitry (70) is further configured to output, via the interface circuitry (80, 82), signaling (63) including one or more notifications in response at least to certain values ​​of the one or more weather metrics (52).

20. 20. The computer system (50) of claim 15, wherein the criterion value (98) for each service area (26) and each time interval (100) is a numerical value having a percentile ranking defined for the service area (26) relative to a corresponding number of past rating values ​​(94) calculated for a corresponding number of previous time intervals (100).

21. 21. The computer system (50) of claim 15, wherein the satellite link parameter is an adaptive home channel symbol rate (HCSR), and for each service area (26) and each time interval (100), the monitored value (92) is the HCSR for each of the subscriber terminals (24) within the service area (26) during all or a portion of the time interval (100).

22. 22. The computer system (50) of claim 21, wherein the rating value (94) for each service area (26) and time interval (100) is calculated as a weighted average of the HCSRs in use by a respective number of subscriber terminals (24) operating within the service area (26).

23. 23. The computer system (50) of any one of claims 15 to 22, wherein the processing circuitry (70) is further configured to correlate a service outage event detected for any particular service area (26) with an indication of weather disruption for the particular service area (26) as indicated by a corresponding weather metric (52) calculated for the particular service area (26).

24. 24. The computer system (50) of claim 15, wherein the satellite communications system (10) includes a plurality of service areas (26), and the processing circuitry (70) is configured to not calculate weather metrics (52) for service areas (26) below a particular service area size threshold, or to not calculate weather metrics (52) for service areas (26) above a particular service area size threshold.

25. The computer system (50) of any one of claims 15 to 24, wherein the satellite communications system (10) includes a plurality of service areas (10), and the processing circuitry (70) is configured not to calculate weather metrics (52) for service areas (26) having a population (28) of subscriber terminals (24) below a certain population size threshold.

26. The computer system (50) of any one of claims 15 to 25, wherein the satellite communications system (10) includes a plurality of service areas (26), and the processing circuitry (70) is configured to not calculate weather metrics (52) for service areas (26) having more than a threshold percentage of offline subscriber terminals (24).

27. The computer system (50) of any one of claims 16 to 26, wherein the processing circuit (70) is configured to exclude a subscriber terminal (24) within a population (28) of subscriber terminals (24) that is newly entering the satellite communications system (10) from consideration in the calculation of the evaluation value (94).

28. 28. The computer system (50) of any one of claims 16 to 27, wherein the weather metric (52) is calculated as a numerical value within a range bounded by a range minimum and a range maximum, one of the range minimum or range maximum corresponding to no weather impact and the other of the range minimum or range maximum corresponding to maximum weather impact.

Images