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Earth Station on Vessels An Update to the NSMA. Spectrum Management 2006 Presented by Ken Ryan, Skjei Telecom May 17, 2006. Earth Station on Vessel 2006. Regulatory Update What’s Happening in Europe Status of U.S. ESV Coordinations Interference Analysis Methodologies
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Earth Station on VesselsAn Update to the NSMA Spectrum Management 2006 Presented by Ken Ryan, Skjei Telecom May 17, 2006
Earth Station on Vessel 2006 • Regulatory Update • What’s Happening in Europe • Status of U.S. ESV Coordinations • Interference Analysis Methodologies • Interference Criteria • Frequency Coordination • Licensing • Proposal for Future ESV Work
Earth Station on Vessel 2006 • Regulatory Update • FCC Docket # 02-10 (FCC DA 04-286) • Released January 6, 2005 • C and Ku-band ESV Co-primary • 15 year license term • New Rule Parts • 25.221 : C-band • 25.222 : Ku-Band • No ESV licenses granted to date
What’s Happening in Europe? • European Conference of Postal and Telecommunications Administrations (CEPT) paper: “Compatibility of Earth Stations on Board Vessels Transmitting Within the Gaps in the CEPT Fixed Service Channel Plan for the Lower 6 GHz Band (5926-6425 MHz)” • Interference Criteria Proposed: • Long Term (single entry) : between -10 & -19 dB (-169 dBW/4kHz, -178 dBW/4kHz) • Minimum safe distances from shore, dependent upon operating conditions. • The ESV antenna main beam axis elevation is not lower than 20°. • The ESV transmits a single carrier per HPA. • The phase noise floor of the ESV carrier does not exceed -120 dBc/Hz. • The p.s.d. of the 1st spectrum side lobe of the ESV carrier is at least 27 dB below the in-band p.s.d. • The ESV e.i.r.p. does not exceed 58 dBW. • The ESV does not transmit when the vessel speed is lower than 10 knots (18,3 km/h). • Limit ESVs to use of Band Gaps as shown in the figure on next slide:
C-band CEPT 30 MHz FS Channel Plan* • Blue shaded areas indicate approximately 25 MHz spectrum is unoccupied, so-called 4% solution. • * Channel plan identical to FCC Part 101.147 i(8) for Lower 6 GHz.
What’s Happening in the U.S.? • Not Much Lately… • The NSMA Examined Analysis and Coordination issues last in 1999 • Some ESVs are being coordinated at C-band • U.S. Coordinators are using the NSMA developed Critical Contour Point analysis method • Current FSS earth station long-term interference objectives are being used: -154 dBW/4 kHz • Use of band gaps being explored, although no proposals to limit ESVs to these bands is proposed • Use of real FS receiver filter curves • No consideration for the motion of the ESV
A Brief Summary of the Current ESV Coordination Process • Steps Required to Coordinate: • Properly characterize the ESV • Route breakpoints • Speed* • Number of approaches* • Analyze operation versus FS systems • Frequency Coordination • Licensing * Only required for in-motion analysis
Characterizing the ESV • Identifying the breakpoints is dependent upon the type of ESV service being provided • Need to identify deep-draft sea lanes • Need to go far enough out to satisfy the FCC rules (300 km) • The route of the ESV must characterize its worst case excursions
Interference Criteria • ESVs currently use existing long and short term interference criteria used by all U.S. coordinated 6 GHz earth stations: • -154 dBW/4kHz long term, -131 dBW/4kHz short term • ITU and TIA documents suggest proper FSS into FS digital interference criteria is: • -146 dBW/MHz long term, -103 dBW/MHz short term • Other options include: • Fractional Degradation in Performance (FDP) criteria, 25% • Performance Degradation Limit (PDL) see TIA TSB-86, five 9’s or 25% performance degradation • Interpolated interference criteria using existing long and short term criteria calculated
Interference Analysis • Currently we are using the Critical Contour Point (CCP) methodology • Current version of the CCP uses a “static” analysis, no benefit for ESV motion is considered • Other analysis approaches are discussed in ITU-R SF. 1585 and 1649 • Other methods which model the ESV motion and collect interference statistics could be examined, for digital FS systems the following three methods could be used: • Long-term objective of –146 dBW/MHz that can be exceeded only 20% of the time and a short-term objective of –103 dBW/MHz that can be exceeded only 0.002% of the time. • Fractional Degradation in Performance • Performance Degradation Limit • The above approaches involve developing interference criteria on a link-by-link basis
Digital FS Interference Criteria Interference Objective = Imax - d
Fractional Degradation in Performance Where: Ii: Linear value of ith interference level. fi: Fraction of time interference from ESV is between the ith interference level and the (i + 1)the interference level NT: Linear value of thermal noise level. In order to account for the 1-dB noise degradation objective as suggested by TIA TSB 10-F, the interference objective is: Imax – FDP – 5.86 (dB).
Frequency Coordination • Process is offshoot of the process developed by the NSMA 6 years ago and is very similar to current coordination model • Provide route and ESV parameters • Currently use the Critical Contour Point analysis method • PCN data is used by other licensees to analyze interference • Incumbent licensees generate cases and response • Coordinator resolves cases in response letter
Licensing • ESV licensee files an initial filing outlining hub and remote parameters • License is a network license essentially providing a blanket authorization for the remote ESVs • Licensee is required to submit a prior coordination showing for each ESV coordinated • ESV is considered licensed once the coordination final report is submitted to the FCC
Proposals for Future Work • Finalize PCN data format and content recommendation • Review international ESV work done, both ITU and CEPT • Examine use of band edge segments for ESV use • Interference analysis methods and criteria for in-motion ESVs • Establishment of an NSMA working group to come to a consensus on these issues, so that ESVs can more easily and realistically be analyzed and coordinated