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SLS-RFM_15-01 (CNES Reply to AI 14-8 on 26 GHzEESS Rec)_imp_for_phase_angles
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Transcript of SLS-RFM_15-01 (CNES Reply to AI 14-8 on 26 GHzEESS Rec)_imp_for_phase_angles
Consultative Committee for Space Data Systems
Space Links Services
RF & Modulation Working Group
Spring 2015 Meeting
Pasadena, CA, USA, 23-27 March 2015
Comments to draft 26 GHz EESS recommendation
SLS-RFM_15-01 Reply to AI_14-08
J.L. Gerner, J.P. Millerioux, J.L. Issler (CNES)
1. Introduction
This document comes in response to AI_14-08 calling for comments to the current draft
recommendation 2.4.23 MODULATION METHODS AT HIGH SYMBOL RATE
TRANSMISSIONS, EARTH EXPLORATION SATELLITES (EES) 25.5-27.0 GHZ BAND,
SPACETO-EARTH, reproduced in annex for reference.
2. Comments / Proposed changes
1 Changes to considering (c)
Page / Section / Table
Page 2.4.23-1, considering (c)
Proposed change
Rewrite considering (c) as follows:
“that the use of now well-established bandwidth-efficient modulation techniques like filtered
suppressed carrier systems will reduce future risks of interference and reduce the need for
coordination”
Rationale
The recommendation 21-2R3, which is referred to in the current considering (c) , concerns
only the 2 GHz and 8 GHz bands; the proposed change will allow to publish rec 2.4.23
without having to wait for a – still hypothetical – approval by SFCG of the inclusion of the
26 GHz EESS band in SFCG Rec 21-2.
2 Considering (d) looks more like a noting
Page / Section / Table
Page 2.4.23-1, considering (d)
Proposed change
Convert considering (d) into a noting.
Rationale
Considerings are supposed to call for a recommends, which is not the case of considering
(d).
3 Considering (g) can be suppressed
Page / Section / Table
Page 2.4.23-1, considering (g)
Proposed change
Delete considering (g).
Rationale
Considering (g) is now redundant with new considering (c)
4 Changes to considering (h)
Page / Section / Table
Page 2.4.23-1, considering (h)
Proposed change
Change considering (h) from
“that with Square Root Raised Cosine filtering QPSK, OQPSK, 8PSK, 16APSK, 32APSK
and
64APSK bit-interleaved coded modulations (BiCM) spectra can meet the SFCG emission
mask for symbol rates in excess of 2 Ms/s with acceptable end-to-end losses;”
to
“that Square Root Raised Cosine filtering QPSK, OQPSK, 8PSK, 16APSK, 32APSK and
64APSK bit-interleaved coded modulations (BiCM) provide high bandwidth efficiency while
offering acceptable end-to-end losses;”
Rationale
Considering (h) should not refer to recommendation 21-2R3, which is only applicable to
bands 2 GHz and 8 GHz.
5 Changes to considering (m)
Page / Section / Table
Page 2.4.23-2, considering (m)
Proposed change
1. Clarify whether “in-band” refers to Rs or (1+alpha)Rs
2. Change from
“without equalization at the receiver”
to
“in case no equalization is implemented in the receiver”
Rationale
Clarifications
6 Typo in noting (4)
Page / Section / Table
Page 2.4.23-2, noting (4)
Proposed change
Change from
“1313-B-1”
to
“131.3-B-1”
Rationale
Editorial
7 Change to FN 6
Page / Section / Table
Page 2.4.23-2, FN 6
Proposed change
Change from
“For example, with CCSDS 131.2-B-1 (table 5-2): ModCod 6 for QPSK, 12 for 8PSK, 17 for
16-APSK, 22 for 32-APSK and 27 for 64-APSK”
to
“For example, with CCSDS 131.2-B-1 (table 5-2): ModCod 6 for QPSK, 12 for 8PSK, 17 for
16-APSK, 22 for 32-APSK and 27 for 64-APSK; or with CCSDS 131.3-B-1 (Annex D):
ModCod 10 or 11 for QPSK, 16 or 17 for 8PSK, 22 or 23 for 16-APSK, or27 or 28 for 32-
APSK”
Rationale
Include also the example of DVB-S2
8 New recommends (3)
Page / Section / Table
Page 2.4.23-2
Proposed change
Insert a new recommends (3) as follows:
“that a mission planning to operate in the 25.5-27.0 GHz band may use unfiltered BPSK,
QPSK or OQPSK, when the channel symbol rates is below or equal to 10 Ms/s;”
And renumber the following recommends.
Rationale
Recommends (2), while inviting to prefer bandwidth-efficient modulations below 10 Msps,
does not indicate what other modulations may still be used. The proposed recommends (3)
will, in particular, keep residual-carrier systems out of the 26 GHz EESS band.
9 Phase imbalance
Page / Section / Table
Page 2.4.23-3, recommends (8)
Proposed change
Change from
“that the modulator’s phase imbalance shall not exceed 3 degrees and the amplitude
imbalance shall not exceed 0.5 dB between the constellation points;”
to
“that the modulator’s phase imbalance shall not exceed 3 degrees and the amplitude
imbalance shall not exceed 0.5 dB between the constellation points for 16APSK and higher
order modulations;”
Rationale
Problem of consistency with recommendation 2.4.12A, which recommends 5 degrees and
0.5dB for BPSK, (O)QPSK, GMSK and 8PSK.
10 EVM values
Page / Section / Table
Page 2.4.23-3, recommends (9)
Proposed change
Add the EVM values
Rationale
The recommends refers to “following EVM values” but these are missing
11 Ratios outer/inner circle
Page / Section / Table
Page 2.4.23-4, Table 2.4.23-1 , column 16APSK
Proposed change
Change from
"g1=R2/R1= 3.15 2.85 2.75 2.60”
to
"g1=R2/R1= 3.15 2.85 2.75 2.70 2.60 2.57”
Rationale
For compatibility with DVB-S2
12 Ratios outer/inner circle
Page / Section / Table
Page 2.4.23-4, Table 2.4.23-1 , column 32APSK
Proposed change
Change from
"g1=R2/R1=2.84 2.72 2.54,
g2=R3/R1=5.27 4.87 4.33"
to
"g1=R2/R1=2.84 2.72 2.64 2.54 2.53,
g2=R3/R1=5.27 4.87 4.64 4.33 4.30"
Rationale
For compatibility with DVB-S2
13 Examples ratios outer/inner circle
Page / Section / Table
Page 2.4.23-4, FN 8
Proposed change
Change from
“See Table 5-1 from CCSDS 131.2-B-1for an example of the use of the values of the ratio of
outer to inner circles.”
to
“See Table 5-1 from CCSDS 131.2-B-1; or Table 9 and Table 10 from ETSI EN 302.307
V1.2.1 (called in CCSDS 131.3-B-1); for examples of the use of the values of the ratio of
outer to inner circles.”
Rationale
To give the reader the full picture
14 Foot Note 9
Page / Section / Table
Page 2.4.23-5, FN 9
Proposed change
Change from
“SRRC filtering can be practically implemented either with baseband filters or with RF post-
amplifier filters each able to fulfill SFCG Recommendation 21-2R2 (see CCSDS 413.0-G-
1).”
To
“SRRC filtering can be practically implemented either with baseband filters or with RF post-
amplifier filters”
Rationale
SFCG Recommendation 21-2R2 only applies to the 2 GHz and 8 GHz bands
15 No constellation mapping in CCSDS 131.0-B-1
Page / Section / Table
Pages 2.4.23-8/9/10/11/12
Proposed changes
Change title for Figure 2.4.23-4 from
“8PSK Symbol Mapping into Constellation (CCSDS 131.0-B-1 and 131.2-B-1)”
to
“8PSK Symbol Mapping into Constellation (CCSDS 131.2-B-1)”
Change in Page 2.4.23-9 from
“Modulations with coding in accordance with CCSDS 131.0-B-1 or 131.2-B-1”
to
“Modulations with coding in accordance with CCSDS 131.2-B-1”
In Figure 2.4.23-6, remove “131.0-B-1”
Change in Page 2.4.23-10 from
“Modulations with coding in accordance with CCSDS 131.0-B-1 or 131.2-B-1”
to
“Modulations with coding in accordance with CCSDS 131.2-B-1”
In Figure 2.4.23-7, remove “131.0-B-1”
Change in Page 2.4.23-11 from
“Modulations with coding in accordance with CCSDS 131.0-B-1 or 131.2-B-1”
to
“Modulations with coding in accordance with CCSDS 131.2-B-1”
In Figure 2.4.23-8, remove “131.0-B-1”
Rationale
There is no constellation mapping in CCSDS 131.0-B-1
Annex : Draft CCSDS Recommendation 2.4.23