modeling of unwanted and blocking interference modes
DESCRIPTION
Modeling of Unwanted and Blocking Interference Modes. European Communications Office Jean-Philippe Kermoal 05 October 2010. Interfering Modes. Unwanted Emissions Case. Blocking Case. Interference Calculations. Interference Criteria. Interfering Modes. Unwanted and Blocking Signals. - PowerPoint PPT PresentationTRANSCRIPT
Modeling ofUnwanted and Blocking
Interference Modes
European Communications OfficeJean-Philippe Kermoal
05 October 2010
EUROPEANCOMMUNICATIONSOFFICE
Nansensgade 19DK-1366 CopenhagenDenmark
Telephone: + 45 33 89 63 00Telefax: + 45 33 89 63 30
E-mail: [email protected] Site: http://www.ero.dk
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 2 05 October 2010
Interfering Modes
Unwanted Emissions Case
Blocking Case
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 3 05 October 2010
Interference CalculationsInterference CalculationsInterfering Modes Interference Criteria
Unwanted and Blocking Signals
SEAMCAT WorkshopMarc Le Devendec / ECO
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Unwanted EmissionsUnwanted Emissions• Victim
fv
Receiver Bandwidth
• Interfering System
fI
Interfering emission mask
fI
Interferer emission mask
SEAMCAT WorkshopMarc Le Devendec / ECO
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Victim LinkVictim Link
Frequency
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Page 6 05 October 2010
Victim Link / Victim ReceiverVictim Link / Victim Receiver
Reception bandwidth
Interference Criterion
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Page 7 05 October 2010
Interfering LinkInterfering Link
Frequency
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Page 8 05 October 2010
Interfering Link/Interfering Interfering Link/Interfering transmittertransmitter
Power
Emission Mask
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Page 9 05 October 2010
Interfering Link/Interfering Interfering Link/Interfering transmitter/Unwanted transmitter/Unwanted emissions maskemissions mask
Default valueerroneous valueSee the following presentations...
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 10 05 October 2010
Interfering Link/Victim receiver -Interfering Link/Victim receiver -> Interfering transmitter Path> Interfering transmitter Path
Att = + 32.4 + 20 x log (f (MHz)) + 20 x log (d (km))Att = + 32.4 + 20 x log (900 MHz) + 20 x log (10 km)
Att = + 111.5 dB
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Page 11 05 October 2010
Simulations...Simulations...
10 km
IRSS Unwanted = P in the victim bandwidth + Ge + Gr – Att (free space)IRSS Unwanted = 12 dBm + 0 dB + 0 dB – 111.5 dBIRSS Unwanted = - 99.5 dBm
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 12 05 October 2010
ResultsResults
N = -110 dBmIRSS Unwanted = -99.5 dBmI/N = -99.5 – (-110) = 10.5 dB ( Calculated by SEAMCAT)Interference Criterion was: I/N = 0 ( Input to SEAMCAT)
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 13 05 October 2010
Results...Results...
Pe = 22.5 dBm
I/N=0dB
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 14 05 October 2010
BlockingBlocking• Victim
fv
Receiver Bandwidth
• Interfering System
fI
Interferer
fI
Rejection of the receiver
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 15 05 October 2010
Blocking: 3 ModesBlocking: 3 ModesUser Defined (dB):User Defined (dB): Rejection at the receiver Rejection at the receiverAttAttBlockingBlocking = Block = BlockUDUD
Protection Ratio (dB):Protection Ratio (dB):AttAttBlocking Blocking = Block= BlockPRPR + C/(N+I) + 3 dB + C/(N+I) + 3 dB
Sensitivity Mode (dBm):Sensitivity Mode (dBm): Maximum Acceptable Value of Power Maximum Acceptable Value of PowerAttAttBlocking Blocking = Block= BlockSens Sens (dBm) – Sensitivity (dBm) + C/(N+I) (dBm) – Sensitivity (dBm) + C/(N+I)
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 16 05 October 2010
But not so differentBut not so different
• Protection Ratio:Interfering Blocking Level = Pe + Ge + Gr – Att – AttBlocking
Where: AttBlocking = BlockPR + C/(N+I) + 3 dB
• If C/(N+I) = - 3 dB AttBlocking = BlockPR - 3 dB + 3 dB = BlockPR
• ....equivalent to User Defined Mode
• If C/I = 0 dBBroadcast PR Mode...
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Page 17 05 October 2010
ExampleExample
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Page 18 05 October 2010
Blocking MaskBlocking Mask
Should be defined at the frequency of the Interferer
Att blocking = 50 dB(e.g. Defined in ETSI Standards)
fV fI
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 19 05 October 2010
SimulationsSimulations
IRSS Blocking= Pe + Ge + Gr – Att (free space) – Att blockIRSS Blocking= Pe + Ge + Gr – Att (free space) – Att blockIRSS Blocking= 33 dBm + 0 dB + 0 dB – 111.5 dB – 50 dBIRSS Blocking= 33 dBm + 0 dB + 0 dB – 111.5 dB – 50 dBIRSS Blocking = - 128.5 dBmIRSS Blocking = - 128.5 dBm
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 20 05 October 2010
ResultsResults
IRSS Blocking Level = - 128.5 dBmIRSS Blocking Level = - 128.5 dBmN = -110 dBmN = -110 dBmI/N = 0 dB (Criterion) always metI/N = 0 dB (Criterion) always met
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 21 05 October 2010
Question?Question?• Can I make simulation for
unwanted and blocking in the same workspace?
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Page 22 05 October 2010
Question: Can I make simulation for Question: Can I make simulation for unwanted and blocking in the same unwanted and blocking in the same workspace?workspace?
• 2 Interference Criteria / 2 runs
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Page 23 05 October 2010
Question: Can I run simulations for Question: Can I run simulations for unwanted and blocking in the same unwanted and blocking in the same workspace in a single run?workspace in a single run?
If the interference criteria are not the same... You can compensate this when defining the
mask (unwanted or blocking)
Blocking: PR mode + Criterion: C/I=0 dBUnwanted: Criterion C/I=10 dB
Remove 10 dB from blocking maskCriterion C/I=10 dB
SEAMCAT WorkshopMarc Le Devendec / ECO
Page 24 05 October 2010
Questions?Questions?
• Thanks for your attention