Attachment Comment

This document pretains to SES-LIC-20030910-01236 for License on a Satellite Earth Station filing.

IBFS_SESLIC2003091001236_341085

ORIGINAL w Wiley Rein & Fielding us anexsneew msunarm, ocms April; 6, 2006 Cart R. Frank polceo now. imnsioe ctankourtcon m imniise RECEIVED 1igot ote BY HAND DELIVERY mssous seuor oc apR — 6 2006 sire ns Ms. Marlene H. Dortch cumiget noomw moe Secretary redenicomnunt smy now mssam m msame Federal Communications Commission "**" 445 12th Street, SW wount on Washington, DC 20554 Re: Call Sign BO30205, File Nos, SES—L1C—20030910—01261, SES—AMD— 20031223—01860, and SES—MOD—20050829—01 185 Dear Ms. Dortch: In accordance with paragraph 58(1 of the Order issued in connection with the above—referenced earth station license," ARINC Incorporated ("ARINC) hereby submits the attached ARINC AMSS System Compliance Report. This Report demonstrates compliance with the aggregate earth station off—axis restrction specified in paragraph S8(k) ofthe Order Very truly yours, CutAal £ | Carl R. Frank Attachment * ARINC Incorporated, Applicationfor Blanet Authortyfor Gperationof Upto One Thousond Techically Idential KueBand TransmitReceive Arborne Moble Statons AbordAireraft Operating in the UnitedState andAdjacent Wauers,Order and Authorization, 20 FCC Red 7583 (InctBur/OET 2008) (Order®)

ARINC AMSS System Compliance Report This report is submitted pursuant to Special Provisions 130 and 131 ofradio station authorization Call Sign EO30205, and confirms that the aggregate earth—station off—axis e.p. spectral density is within the levels specified in ARINC‘s SKYLink®"" Aeronautical Mobile—Satellte Service (AMSS) system licensing order and the design parameters in paragraph 24 of that order.! The data provided in this report showthat SKYLink"" operation complies, with a significant margin, to the conditions of the licensing order. Aggregate Off—axis E.L.R.P. Spectral Density In order to protect Fixed Satellte Service operations from harmfulinterference in the 14.0—14.5 GHz band, ARINC asserted in ts AMSS application that the aggregate of—axis e.. of simultancously transmitting SKYLink"" AES terminals would be kept one—dB below the VSAT emission envelope atleast 99.999 percent ofthe time. The FCC subsequently authorized mobile satellite communications operation beginaing April 6, 2005 stipulating that: ©130 — ARINC shall manage uplink operation of the SKYLink*" System so that the probability that aggregate earth—station off—axis e.ip. spectral density will exceed a one—dB margin below the levels specified in the table belowis never more than 0.001 percent. To ensure continuing compliance with this requirement, ARINC shall monitor usage pattems and traffic flow so that it can detect and adjust for anymaterial discrepancies from the predictive assumptions identified in [ARINC‘s Engineering Exhibit of June 3, 2004]." See Order and Authorization, DA 05—1016, released April 6, 2005, for formula." "131 — Twelve months after release ofthis order, ARINC shall submit evidence demonstrating compliance with the ageregate earth—station off—axis c.ir.p. restriction specified in the preceding sub—paragraph, The showing shall reflect the most—recent available data and shall disclose any discrepancies between previous predictive assumptions and conditions actually encountered in commercial operation and explain what compensating adjustments have been made." Analysis of substantial data collected during the frst year of operation shows SKYLink®"" to be in compliance with these terms. ! See ARINC Incorporated Applicationfor Blanket duthoripfor Operation ofUp to One Thousand Techically HeicalKi—Band TransnitReceive Arborne Moble Staions AbourdAireraf Operating in the UnitedStatesand «Adjacent Weter, Ordeand Authorzation, 20 FCC Red 7553 (Aprl 6 2008) (SKYLink" Order") * See Extibit 1, Reply to Supplemental Comment ofThe Bocing Company, ARINC IncorporatedSKYLink®" Application,File Nos. SES—L1€—20030910—01261 & SES—AMD—20031223—01860, Engineering Response to Bocing YJn 3, 2004 Engineering Exhibit‘)

Variables and Assumptions Affecting Aggregate Off—axis E.L.R.P. Spectral Density On June 3, 2004, ARINC filed its Engineering Exhibit with the FCC wherein a Monte Carlo simulation was used to demonstrate that the SKYL ink®" system would meet the interference criteria ultimately incorporated in the SKYLink*" Order. In the absence of operational data, a number of assumptions were used in this simulation. Tables 1 and 2 identify assumptions for which data now exists and describe what that data now consists of Table 1. Factors Affecting AES ELR.P. Parameter Original Estimates and Assumprions Current Antenna Patiorn * Varitions between AES antennas have No change independent, uniform ampltude varition ove arange of041 0B * Greater ofpline or Heplane values No change used at each point on the mask. Poner *~ Nominal espectrl densiyfor ETRF was memsured on all ighs CONUS coverage area assumed to be (Oct 2005 through Fob,2006) «53 dowa kite * Abrerat assumed t be unformly ‘The actual ierat distibation oAight disribaed within AMC—1 suelite paths and fight durations within the transpondefootprint (Nort American AMC—6footprint wa recorded. beam coverngo) * Variations n transponder GT assumed The measired ABS einp.includesall to have indepedent,uniform +2 dB variations in ransponder GT ampltude variaton * Enor in system power contrl assumed No change. Longterm measured to have independentuniform +0.5 stablit ofthe power control system is 4Bampltude varition. +/—04 db. * The contribution ofthfxed Ground No change. Earh Sution toofFaxiscirp. assumed small in compared to asingle AES and does t change over time. Fointing Ervers * Fach SKYLink®" AESassumed io No change. have ms poiting eror of0.1 degrec (ARINC License Applcation Extibit 3)This is modeled as an independent zero—mean normal disibution with a standard deviation of0.1 deree. * Aifame flxureforirert types No change served by SEYLink®" assumed toless than a degres, per thairfame manifacture. Thi is modeled as an ependent, zero—mean normal distibaionwithstandard deviation o 0. degree Data Rare + ABS einp requred o "close e Ink" «Th measired ABS en includes any is drecly proportinalt the dta rate non—linear response. ——Normal data trnsmisionrate 128000 bits persecond (128 kbps) ~Logridata rae: 32 kbps

Table 2. Independent Variables Used to Derive Peak Demand Parameter |_Original Estimates and Assumpiions Curem Demand per + Business demand per user was patemned + Aciual demand was measured User atter 30—day monthlysend and receive volume for ARINC corporae Itemet trae + A 60/40splt between business use and +. Measured demand includes theactual Intemetrereationaluse was assumed businesecreationalmix * Recreational use assumes a 27 atlo of + Measured demand includes theactual Retun LinktoForvard Link taff rato of Return to Forward Link raffc * Monthly demand was compressed in. + Actal weekday demand was measured. 20 daysto estimate daily usedemand. + Peak busy—hour demand wasestimated + Actul busy—hour demand was measired bycompressing tol daily raffeino 4 hous. + Distribation ofmessage sizes assumed to + Measired demand includes actual mixof be Gausianto account foinfequent message sizeand types (VPN, FAX, e— butoccasionl very long messages: mall Inernet,cte) +. Link overhead (TCPTP acknowledge= + Conservativeprotocol overhend 0f40% mens)included in estimate adided t demand ‘sers per + For businesststhis number vas * Measureddemand includes wafi from Ars assumed t be on all wers on allarcrt Data Rate + Nominaldta transmission mie is + Nochange. 128,000 bits ersecond (128 kbps) Error Rate| + Maximum aceeptable biteror rte: 1 in + No change 100.000 1 x 105. 2. Most Recent Data As requested by the FCC, the most recent available data was used to prepare this report. The oldest satisties relate to geographical coverage stating October 17, 2005 when SKYLink®" service was transferred from SES—Americom satellite AMC—1 (transponder 16) to AMC—6 (transponder 12). The move to AMC—6 improved CONUS coverage and resulted in an overall reduction in return—link power because ofimproved G/TT contours, Figure 1 depicts the AMC—6 coverage area using actual fights during the period October 17, 2005 to February 28, 2006. The circular area over New Mexico delimits the "no transmit zone" boundary at 50,000 feetrequired to protect TDRSS facilities near White Sands." This exclusion zone is both range and altitude dependent, which means that aireraft below certain altitudes may communicate during final descent or takeo? atairports within the boundaryshown. The actual distribution ofmeasured i. for all flights was determined from data collected in January and February 2006 in order to reflect the latest hardware and software improvements to the AES transceiver. * Coortination Agreement Between NASA and ARINC for Operationof the ARINC SKYLink AMSS in the 14.0— 14. Oz Band, sgned by NASA on September3,2004

uen «use Hag) —me ce —so cno «10 —co torpue Figure 1. SKYLink»" CONUS Coverage Area and Flight Paths Traffic data collected from February 15, 2006 through March 15, 2006 were used to validate peak demand assumptions in the simulation. These data included all facsimile, VPN traffc and Internet traffic over SKYLink®". The ARINC traffic monitoring system routinely records byte counters in the ABS router onee a minute for all active aireraft. This count is conservative since it includes all data appearing on the router LAN, whether or notit passes through the satellte Hink. A forty—percent burden was added to the traffic count as a conservative estimate of the TCP/P protoco! overhead. Figure 2 llustrates the variation in weekday traffiduring the busiest hours ofthe day and corresponds very closely with our earlier assumptions. Even the observed 3:8 ratio of Return—link to Forward—link traffic in Figure 2 compares favorably with the original estimates. The rather broad peak from 3PM to GPM EST is attributed to active aireraft being in multiple time zones. Data at one—second resolution is routinely collected by the Network Operating Center (NOC) on all active aireraf, This data was examined from January 1, 2006 through February 28, 2006 (the latest period available) for all possible occurrences of simultancously transmitting AES. The greatest number of AES appearing within any two—second window was four and this occurred 34 times, or 0.00007% ofthe time. A two—second stiding window was used to allow for any transmissions that spill into the next second. The actual probability of simultancous transmissions may be considerably less than this because the NOC pollsall active unitsat randomized intervals when they are not transmitting.The 0.00007% figure is also conservative

because many transmissions are completed within a fraction of a second and do not overlap any another transmission 1 an ue no e he un un uo me un ue an no ns no neagm Figure 2. Hourly Variation in SKYLink®~" Send and Receive Traffic On March 7, 2006, for example, when the greatest hourly demand was observed, four aircraft were logged on to the network, Only two of those aircraft, however, could have possibly transmitted simultancousty and this could only have happened during a single 20 minute interval. The greatest traffic offered by either user during any ofthose 20 minutes required less than 8 seconds to ransmit and, on average, amounted to less than 2 seconds of use per minute. 3. Analysis of Most Recent Data Measured values of AES power for actual geographical locations and dwell times were found to be substantially lower than the estimates used in the original simulation and exhibited a broader range of values. While a lower average er.p. reduces the probability ofexceeding the aggregate off—axis limits, any increase in the percentage of AES toward the upper end of the distribution has an adverse effect. Such an increase could arise, for example, if satellte uplink G/TT contours and downlink e.ip. contours are not congruent. In Paragraph 43 of the SKYLink*®" Order, the FCC asked that we "disclose the extent, if any, to which the downlink footprint extends beyond the minimum G/T control and explicitly account for the consequent impact on ageregate e.ip. The impact of any such mismatch was determined by rerunning the Monte Carlo simulation using the actual c.ir.p. distribution and measured peak demand. After 100 million trals, a sufficient number of low—probability events were observed to determine that the SKYLink®""

system is operating below a 0,0001% chance of exceeding the aggregate offaxis e.r. This result is consistent with the observation in the previous section that two or fewer actual simultancous transmissions occurzed during the most recent period for which data was available. In Paragraph 46 ofthe SKYLink*"" Order, the FCC asked that we address error factors in the system used to calibrate and monitor ABS e.rp. This system consists of 1) a test signal generator and reference transmitter co—located with the hub earth station, which generates a reference waveform for the hub uplink transmission, 2) a precision uplink power contral unit, which maintains a constant signal level atthe satellite, 3) a 4.5—meter antenna conforming to the requirements of Section 25.209, and 4) a receive signal processor to determine if an adjustment is regquired on the uplink power control or the AES. Based on measurements after the move to AMC—6, this system has a demonstrated long term stability of +/~ 0.4 dB. This is slightly better than the original estimate used in the Monte Carlo simulation. 4. Conclusion The Monte Carlo simulation used previously to account for the many factors affecting aggregate off—axis e.rp. was run using actual trafic demand plus observed power levels over the entire satellte footprint." Even with the addition of 40 percent protocol overhead during peak demand periods, the chance that agaregate earth—station off—axis e.i.p. spectral density wll exceed a one—dB margin belowthe levels specified in the SKYLink®®" icense are at least two orders of magnitude less than the allowed 0.001 percent. ARINC will continue to monitor SKYLink*"" performance and make any adjustments necessary to maintain compliance with it license. "Fora description ofthis Monte Carlo model, see ARINC‘s Je 3, 2004 Engineering Exhbit

€158E Carino Rea cesca arooe 1om Tw omarezam Fa: oo on March 16, 2006 Mr. William M. Kolb Project Manager, SKYLink Program ARINC, Inc. 251 Riva Road Annapolis, Maryland 21401 410—266—4017 SKYLink Interference Report Dear Mr. Kolb: 1 have had our Network Operations Center (NOC) search through our customer service ticket data base from the period April 6,2005 to present for any record ofinterference reports from the SKYLink network operating under carth station license E030205. There were no reports ofinerference from the SKYLink network made by other users on AMC— 6, nor were there any from users ofor operators ofthe adjacent satelites. Regards, _ @amaf J b’i«‘[i Dary! T. Hiter, PE. Senior Systems Engineer

SESAAMERICOM An SES GLOBAL Compary Frederck D. Cain Director, Transponder Capacity EnterriseSolutons March 20, 2006 Mr, William M. Kolb Project Manager, SKYLink Program ARINC 2551 Riva Road Annapolis, MD 21401—7468 Re: SKYLink Interference Report Dear Bill SES Americom has searched ts records for any interference issues pertaining to ARINC. The search covered the period oftime from April 6, 2005 through today. The search was conducted on AMCI transponder 16 and AMCG transponder 12. To the best of our knowledge there were no known instances of interference caused by the ARINC operation of traffic on the above transponders. SES Americom is pleased to have ARINC as a client with a clean operational record. If there are any questions on this matter please feelfree to contact me directly. Sincerely; /J casebty lekkat nenmricne 1ms1 on | S one ts |wivinmem mt | omm msonen



Document Created: 2003-10-28 14:29:48
Document Modified: 2003-10-28 14:29:48
© 2024 FCC.report
This site is not affiliated with or endorsed by the FCC