CEPT
SE40(14)016
ECC
Electronic Communications Committee
To: WGSE Project Team SE40
Biel, Switzerland, 10 – 11 June 2014
Date issued:
3 June 2014
Source:
Subject:
Solaris Mobile Limited
Comments and proposed modifications to the Working Document on
Aeronautical CGCs
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Summary:
Solaris Mobile (SML) provides comments and proposes modifications to the Working Document
on Aeronautical CGCs.
Proposal:
SE40 is invited to consider the comments made in this contribution and the proposed
modifications to the Working Document on Aeronautical CGCs.
Background:
A first preliminary study by Inmarsat on aeronautical CGCs has been considered by SE40 date
issued 11 March 2014.
1)
Scenarios to be considered in the studies and regulatory measure to be
recommended to FM44/WGFM:
1. Within the EU: ECC/DEC/(06)09 states, “that mobile satellite systems operating in
accordance with this Decision shall ensure that the interference between a mobilesatellite system implementing CGC and another mobile-satellite system is duly
considered during the inter-system coordination, taking into account relevant CEPT
studies and including assessment of unwanted emissions;”.
The two MSS operators have exclusive assignments in the EU: MSS/CGC for SML
exclusively in 1995-2010 MHz and 2185-2200 MHz, and Inmarsat MSS/CGC in 19801995MHz and 2170-2185MHz.
The ECC decision above assumes that both MSS licensees are operating similar
MSS/CGS systems. In the event that one MSS operator chooses to deploy an
aeronautical system and the other does not, then additional mitigation measures, such
as additional geographic isolation or the need for a guard band(s) with respect to the
adjacent mobile allocations or with respect to SML 15 MHz exclusive assignments.
2. Outside the EU: Is governed by ITU processes and operations in the 2x30 MHz
depends on frequency coordination. Inmarsat's authorization is solely for and within the
EU. Therefore, the co-channel interference case needs to be evaluated within 1980 –
2010 MHz and 2170 – 2200 MHz. This should be reflected in the Working Document.
SML claims that any additional mitigation measures or guard band(s) necessary for operating
aeronautical CGCs should be implemented by Inmarsat within their 15MHz assignments, i.e. the
operator of Inmarsat Aero CGCs should not put any undue constraints on SML operations (or
mobile operations in adjacent bands).
Proposed conclusion and recommendation to FM44 and WGFM:
”Any additional mitigation measures or guard band(s) that is necessary to ensure protection of
ECN operations (UMTS, LTE, etc.) or MSS/CGC operations in adjacent bands from
aeronautical CGC interference, should be implemented within the 15 MHz spectrum assignment
of the MSS operator that is operating the aeronautical CGC.”
Proposed conclusion and recommendation to ETSI and 3GPP:
SML recommends SE40 to send a liaison statement to ETSI and 3GPP indicating that this study
is in progress and invite comments.
2)
Proposed modifications to the Working Document
Solaris Mobile proposes modifications in the below attached working document. There are also
comments and questions for clarification from Solaris Mobile in relation to the working document
on Aeronautical CGCs, as provided in Annex below and in attached working document.
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Annex: List of comments and questions for clarification in relation to the Working
Document on aeronautical CGCs (also reflected in the Working Document):
Page 3, Figure 2 – Inmarsat Spectrum is only exhibited. Label as “Inmarsat Spectrum Band” direction of the communication links for adjacent terrestrial and Inmarsat Spectrum Band for
Aero CGC systems.
Page 4, Table 1 – Define “MCA”
Page 6, Table 2 - Need to take into consideration coordination rules to be established with SML
and/or technical limits. Considering that the use of AERO-CGC is a new concept, not mentioned
or envisioned in ECC/DEC/(06)09. ECC/DEC/(06)09 states, “that mobile satellite systems
operating in accordance with this Decision shall ensure that the interference between a mobilesatellite system implementing CGC and another mobile-satellite system is duly considered
during the inter-system coordination, taking into account relevant CEPT studies and including
assessment of unwanted emissions;”.
Page 7, (4.1) – Please clarify and discuss what ETSI standard the ground stations parameters
are expected to follow.
Page 7, Table 3 – Please clarify the BS output power at antenna connector. Is 70 – 150 Km the
maximum expected cell radius, or the average and what is used in the analysis scenarios?
Page 8, Figure 5 – Please clarify the vertical antenna pattern for the CGC station. The pattern
provided looks artificial, not from a typical production model pattern. What is the vendor and
model number?
Page 8, Table 4 – Please clarify the value of Thermal Noise floor. –174 dBm is the thermal
noise floor at room temperature in a 1-Hz bandwidth - seems like this value would not apply to
an aircraft-bourne system
Page 8, Table 4 – Please clarify the transmitter max/min power level. As indicated in ETSI TS
136-101, the UE Maximum Output Power is +23 dBm. As indicated in ETSI EN 301 908-13,
Section 4.2 - Transmitter Maximum Output Power: 23 dBm for Power Class 3, the range of UE
maximum output power for the various power classes are specified in TS 136 101. 3GPP Band
14 is the only one with +31 dBm as a maximum power.
Page 8, Table 4 – Please clarify where the value number comes from for Adjacent Channel
Leakage Ratio. In ETSI EN 301 908-13 V6.2.1 (2013-10) pages 33 to 34 the value is between
29.2 to 35.2
Page 9, Figure 6 – Please clarify the proposed modulation model (red curve) for compatibility
studies with “filled null” and how the Aircraft station parameters are implemented. Redirecting
some of the antenna's energy to fill the pattern nulls in the direction towards 0 degrees?
Page 10, Table 5 - Please clarify the transmitter max/min power level. As indicated in ETSI TS
136-101, the UE Maximum Output Power is +23 dBm. As indicated in ETSI EN 301 908-13,
Section 4.2 - Transmitter Maximum Output Power: 23 dBm for Power Class 3, the range of UE
maximum output power for the various power classes are specified in TS 136 101. +31 dBM
only maximum for 3GPP band 14.
Page 10, Table 6 – Antenna downtilt is assumed to be 3 degrees. Why is this assumed? Many
ECN antennas, especially in suburban or rural areas may be at 0 degrees and some, on
hillsides may even be uptilted. Shouldn’t you assume worst case?
Page 14, Section 5 - The Analysis and Results should determine the necessary geographic
isolation in order to not interfere with SML and all potentially interfered-with system components.
Page 14, Section 5 – See SML comment on page 14. Does the methodology follow the figure
and can we add a figure showing the analysis setup diagram?
Page 14, Section 5.3 – Some typographical errors and frequency should be 2110 MHz not
2210 MHz
Page 15 – Consider the Front-to-Back ratio of the Antenna and the effects of up-tilting 10
degrees. Need to examine the effects of the back lobe power (which is down tilted) and directed
to co-sited base stations and users.
Page 15 - Statement is not true. From the graphs in figure 10, the PFD of the aero CGC system
for < 50 meters is 7 dBW/m^2 difference and from 350 meters to 1370 meters there is a greater
than 10 dBW/m^2 difference because of up-tilting the antenna. Is there a PFD limit and what
would be the geographical separation distance requirement?
Page 16, Table 10 - Table 4 of ECC Report 210 has 46 dBm not 47 dBm. Also, ACLR from
Table 4 of ECC Report 210 has 45 dB not 44.2 dB.
Page 18 – Some typographical errors and clarification needed.
Page 19 Results in Figure 12 – Need clarification, especially the sentence that starts with,
“Additionally, this suggests installing the CGC base stations of different systems operating in
adjacent frequency range in the same area…”. Solaris Mobile calculates, using worst case
values for all parameters, an I/N of +24.6 Therefore, we would like to verify the calculations
used by Inmarsat. Also, need to consider the analysis case where the Aero Terminal at 19802010 MHz Transmitting maximum power and is near and interfering to a DA2GC Station.
Page 20, Figure 14 - Figure 14 illustrates the I/N at the receiver without considering an ACLR of
11 dB (ACIR= 11dB). Please clarify why without considering an ACLR of 11 dB. Solaris Mobile
calculates using worst case values for all parameters an I/N of +12.6 (ACLR of 11 dB (ACIR=
11dB)). SML would like to verify the calculations used by Inmarsat.
Page 20, Figure 15 - Figure 15 illustrates the I/N at the receiver without considering an ACLR of
30.3 dB, which leads to a ACIR value of 30.1 dB. Please clarify why without considering an
ACLR value. Solaris Mobile calculates using worst case values for all parameters an I/N of
+12.3 (considering an ACLR of 30.3 dB, which leads to a ACIR value of 30.1 dB). SML would
like to verify the calculations used by Inmarsat.
Pages 21 – 28 – Unclear how scenarios 6 and 7 take into account the movement of the
Airplane and the mobility of the Mobile Video Link (Helicopter at 150m height).
Page 23, Table 11 - Results for this worst case scenario shown in Table 11 fail the threshold
level of I/N = -6 dB by a considerable amount. What are the required mitigation measures?
Page 23 – Is 20 dB typical and accurate for worst case? I.e. it looks like this angle is between
25 to 35 degrees from the patterns show in figure 7 and 8.
Page 28 - CONCLUSION AND RECOMMENDATION added by SML
Summary of technical results:
TBD and;
The Analysis and Results should determine the necessary constraints or additional mitigation
measures to be required of the aeronautical operator's spectrum. Mitigation measures or
restrictions could include, geographic isolation, Frequency separation (Guard Band), Extended
filtering, Power reduction, Shielding (including natural terrain shielding), Signal
processing/interference nulling, in order to not interfere with SML and all potentially interferedwith system components.
Regulatory recommendation to FM44 and WGFM:
Any Guard Band(s) that would be necessary to ensure protection of MSS and conventional
CGCs of one MSS operator, or of UMTS operations in adjacent bands from interference, from
Aeronautical CGCs of the other MSS operator should be entirely implemented within the 15
MHz spectrum assignments of the MSS operator that is operating the Aeronautical CGCs.
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