Capture of Space Notices ADD

1
Implementation ofCarrier to Interference ratio
(C/I) calculations
By Philippe AUBINEAUSpace Service
Department RADIOCOMMUNICATION BUREAU
GENEVA, 15 - 19 NOVEMBER 2004
2
Part I Appendix 4 data elements and Carrier to
Noise (C/N) ratio
Part II Type of carriers and Required Carrier
to Interference (C/I) ratio
Part III Type of carriers and C/I ratio
adjustment factor calculation methods
3
Part I Appendix 4 data elements and Carrier to
Noise (C/N) ratio
Part II Type of carriers and Required Carrier
to Interference (C/I) ratio
Part III Type of carriers and C/I ratio
adjustment factor calculation methods
4
Up and Down Links AP4 Elements for (1)Carrier
to Noise (C/N) Ratio Calculations
5
Up and Down Links AP4 Elements for (2)Carrier
to Noise (C/N) Ratio Calculations
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Up and Down Links AP4 Elements for (3)Carrier
to Noise (C/N) Ratio Calculations
Service Area ?
Service Area? Associated Earth Station(s)
location (Item C11a)
C/N? (Psta maxGTx Sta maxG(?)Sat Rx) /
(KTSatB(?emis.)FSL?freq. )
C/N? (PSat maxG(?)Sat TxGRx Sta max) /
(KTStaB(?emis.)FSL?freq. )
C/N ? or ? greater of Carrier to Noise ratios
to meet link performanceunder clear sky
condition or to meet link short-term objectives
(item C8e1)
K is the Bolzmans Constant -228.6 dB (J/K)
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Up and Down Links AP4 Elements forC/N
Calculations Database Structure (1)
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Up and Down Links AP4 Elements forC/N
Calculations Database Structure (2)
or
Sub-Group or frequency assignment level
Assoc. Earth Station(s)
Emissions
C/N (PmaxGSta maxG(?)Sat) /
(KTBFSL(freq.). )
K is the Bolzmans Constant -228.6 dB (J/K)
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Up and Down Links AP4 Elements forC/N
Calculations Database Structure (3)
or
Sub-Group or frequency assignment level
Assoc. Earth Station(s)
Emissions
or
or
C/N (PmaxGSta maxG(?)Sat) /
(KTBFSL(freq.). )
K is the Bolzmans Constant -228.6 dB (J/K)
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Up and Down Links AP4 Elements forC/N
Calculations Database Structure (3)
or
Sub-Group or frequency assignment level
Assoc. Earth Station(s)
Emissions
or
or
or
or
C/N (PmaxGSta maxG(?)Sat) /
(KTBFSL(freq.). )
K is the Bolzmans Constant -228.6 dB (J/K)
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Up and Down Links AP4 Elements forC/N
Calculations Database Structure (3)
or
Sub-Group or frequency assignment level
Assoc. Earth Station(s)
Emissions
or
or
or
or

• all assigned frequencies in the group,

C/N (PmaxGSta maxG(?)Sat) /
(KTBFSL(freq.). )

• all Associated Earth Stations within the Service
  Area of the group, and in particular for all
  Earth Station Antenna Sizes

K is the Bolzmans Constant -228.6 dB (J/K)
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Up and Down Links AP4 Elements forC/N
Calculations Database Structure (4)
-10dB
Only one Group
-6dB
-2dB
Sub-Group or frequency assignment level
Assoc. Earth Station(s)
Emissions
? Risk that C/N ratio values may not meet the
link requirements
? Solution would be to split the Service Area
into 3 separate Groups
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Up and Down Links AP4 Elements forC/N
Calculations Database Structure (5)
Group No. 1
No. 1
-10dB
Group No. 2
No. 2
-6dB
Group No. 3
No. 3
-2dB
Sub-Group or frequency assignment level
Assoc. Earth Station(s)
Thus, a C/N objective for a given emission (i, j
or k) is valid for one type of Associated Earth
Station and still for all assigned frequencies
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Part II Type of carriers and Required Carrier
to Interference (C/I) ratio
Part I Appendix 4 data elements and Carrier to
Noise (C/N) ratio
Part III Type of carriers and C/I ratio
adjustment factor calculation methods
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Type of carriers and Required Carrier to
Interference (C/I) Ratio
or
Sub-Group or frequency assignment level
Assoc. Earth Station(s)
Emissions
or
or
or
or
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Type of carriers and Required Carrier to
Interference (C/I) Ratio

• See Section II of Appendix 1of the Radio
  Regulations

• Examples of designation of emission

• " 36M0F3F
• " 36M0G7W

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Type of carriers and Required Carrier to
Interference (C/I) Ratio

• 4 types of carriers defined as follows

• Analogue (TV/FM)1st symbol "F" (i.e. frequency
  modulation) 3rd symbol "F" (television(video))
  or "W" (combination)(e.g.
  36M0F3F-- or 36M0F8W--)

• Analogue (other than TV/FM)1st symbol "F"
  (i.e. frequency modulation) 3rd symbol ltgt "F"
  and "W" (e.g. 36M0F3E--)

• Digital1st symbol "G" (i.e. phase
  modulation)(e.g.36M0G3W--)

• Other1st symbol ltgt "F" and "G" (e.g.36M0P3N--)

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Type of carriers and Required Carrier to
Interference (C/I) Ratio

• Required C/I ratio of the desired signal

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Type of carriers and Required Carrier to
Interference (C/I) Ratio

• For most of the cases, Required C/I ratios of the
  desired signal are derived from its C/N
  objectives,which are either

• Submitted under RR App. 4 Annex 2 Item C.8.e.1
  (see also note 1 below)

or, in absence of submitted values

• Calculated as explained before in Part I, i.e.

C/N (PmaxGSta maxG(?)Sat) /
(KTBFSL(freq.). )
K is the Bolzmans Constant -228.6 dB (J/K)
Note 1 Calculations of Harmful Interference
generated by a network under examination into
other networks are based on the minimum value
between the submitted C/N objectives and the
calculated C/N objectives
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Part III Type of carriers and C/I ratio
adjustment factor calculation methods
Part I Appendix 4 data elements and Carrier to
Noise (C/N) ratio
Part II Type of carriers and Required Carrier
to Interference (C/I) ratio
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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Interference Margin calculation

MargindB C/Iadjusted dB (Required C/I)dB
? harmful interference if Margin lt 0
C/Iadjusted dB CdB ( IdB (Adjustment
factor)dB )
Where the Adjustment factor is always ? 0 in dB,
i.e. C/IdB ? C/Iadjusted dB
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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Adjustment factor calculation methods

METHOD 3 Adjustment factor derived from
Relative Protection Ratio Masks
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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Method 1 Desired and Interfering Overlapping
  Bandwidth to Interfering Bandwidth Ratio
  Adjustment Factor (Ia ? 0)

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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Method 1 Desired and Interfering Overlapping
  Bandwidth to Interfering Bandwidth Ratio
  Adjustment Factor (Ia ? 0)

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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Method 2 Desired Bdwidth and Interf. Equivalent
  Bdwidth Overlap. to Interfering Equivalent
  Bdwidth Ratio Adjust. Factor

• Generally for Interfering Signals of Analogue
  Type (with Gaussian Distribution power
  spectrum)

• Calculate the Equivalent Bandwidth (BWeq) as
  Bandwidth with uniform maximum power density (P
  dens max), while using the maximum Peak
  Power (P peak max)

Where P peak max is in dBW (App4 Annex 2 item
C8a1/C8b1) P dens max is in dBW/Hz (App4 Annex 2
item C8a2/C8b2)
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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Method 2 Desired Bdwidth and Interf. Equivalent
  Bdwidth Overlap. to Interf. Equivalent Bdwidth
  Ratio Adjt. Factor (Ia ? 0)

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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Multiple Interfering narrowband Carriers

? Interfering transponder fully loaded with N
narrowband carriers, where N is maximized by
- the interfering transponder bandwidth
(App4 item C3a),
and - the maximum total peak
power (App4 item C8d1)
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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Method 3 Relative Protection Ratio adjustment
  factor (? 0)

• Relative Protection Ratio adjustment factor is
  derived from the relevant Mask taking into
  account the frequency offset.

• The relevant Relative Protection Ratio Mask is a
  function of the desired and interfering signals
  necessary bandwidths

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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Method 3 Relative Protection Ratio adjustment
  factor (? 0)

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Type of carriers and C/I Ratio Adjustment
factor calculation methods

• Examples of adjustment factors

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References

• Recommendations ITU-R S.741-2, etc

• Rules of Procedure relating to No.11.32 of the
  Radio Regulations

• SPS / MSPACE software manual