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Basic examples of setting simulations

Basic examples of setting simulations. European Communications Office Jean-Philippe Kermoal (ECO) October 2010. Outline. Step 1: How is the dRSS calculated? Step 2: My first interference probability calculation Step 3: Probability of interference

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Basic examples of setting simulations

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  1. Basic examples of setting simulations European Communications Office Jean-Philippe Kermoal (ECO) October 2010

  2. Outline • Step 1: How is the dRSS calculated? • Step 2: My first interference probability calculation • Step 3: Probability of interference • Step 4: Where does the interference come from?

  3. Step 1: How is the dRSS calculated?

  4. You will learn from Step 1 how to ... ✓ • Define Victim receiver (Vr) • Operating frequency • Receiver bandwidth • Antenna Characteristics • Interference criteria • Noise floor • Define Wanted transmitter (Wt) • Tx power • Antenna characteristics Position the Wt vs Vr ✓ Calculate the dRSS Test propagation model Launch simulation Extract dRSS vectors ✓ ✓ ✓ ✓ ✓

  5. SEAMCAT scenario iRSS dRSS Interfering Transmitter (It) Victim Receiver (Vr) Interfering link Victim link Wanted Transmitter (Wt) Wanted Receiver (Wr)

  6. Victim Receiver (Vr) dRSS Victim link Wanted Transmitter (Wt) Victim Link

  7. Define Victim frequency

  8. Define Victim Receiver (VR)

  9. Define Wanted Transmitter (Wt)

  10. Uncorrelated cases mode Noise limited Network User-defined Radius Traffic limited Network Wt ↔ Vr location Correlated distance (origin = Wt) Correlated cases mode Position of the Wt (1/2)

  11. Delta X = 2 km y dRSS (2 km,2 km) Delta Y = 2 km Victim Receiver (Vr) Victim link (0,0) x Wanted Transmitter (Wt) Position of the Wt (2/2)

  12. Calculation of the dRSS • dRSS = Pe+Ge+Gr-L • dRSS = 30(dBm)+9 (dBi)+9 (dBi)-101.5 (dB) • dRSS = -53.5dBm • L = 32.5+10log(8)+20log(1000)) • L = 101.5 dB

  13. Testing propagation model

  14. Launch simulation

  15. Extract dRSS

  16. Output display

  17. Step 2: My first interference probability calculation

  18. You will learn from Step 2 how to ... ✓ Position the Vr vs It (i.e. Victim link vs Interfering link) ✓ • Define Interfering transmitter (It) • Tx power • Antenna Characteristics • Set the emission bandwidth ✓ Calculate the iRSS ✓ Calculate the probability of interference

  19. Interfering Link

  20. Interfering Frequency

  21. Define Interfering Transmitter (It) • P(dBm/Bref) = Pe (dBm)+Att(dBc/Bref) • 33 (dBm/200KHz) = 33 + 0 (dBc/Bref)

  22. Uncorrelated cases mode Uniform density (nactive interferers) None (nactive interferers) Closest (single interferer) Vr ↔ It location Wr/Wt It /Vr It /Wt Wt /Vr Correlated cases mode Position of the Vr vr It (1/2)

  23. Wanted Receiver (Wr) Position of the Vr vr It (2/2) dRSS Wanted Transmitter (Wt) iRSS Interfering Transmitter (It) Victim link Delta Y = 4 km Interfering link Delta X = 4 km Victim Receiver (Vr)

  24. Calculation of the iRSS • iRSS = Pe+Ge+Gr-L • iRSS = 33(dBm)+11 (dBi)+9 (dBi)-(32.5+10log(32)+20log(1000)) • iRSS = -54.5dBm

  25. Step 3: Probability of interference

  26. You will learn from Step 3 how to ... ✓ Extract the Probability of Interference in .... ✓ Compatibility calculation mode ✓ Translation calculation mode

  27. Probability of interference • The probability of interference could be calculated by the ICE with reference to the following choice of input parameters: • Calculation mode: compatibility or translation • Which type of interference signal is considered for calculation: unwanted, blocking, intermodulation or their combination • Interference criterion: C/I, C/(N+I), (N+I)/N or I/N

  28. Compatibility calculation mode • the C/I (i.e. dRSS/iRSS) can be derived: • dRSS/iRSS = -53.5-(-54.5) = 1dB

  29. Translation calculation mode

  30. Step 4: Where does the interference come from?

  31. You will learn from Step 4 how to ... ✓ Modify the Unwanted Emission Mask ✓ Calculate the iRSS unwanted ✓ • Calculate the iRSS blocking • user-defined mode • Sensitivity mode • Protection ratio mode ✓ Extract probability of interference (i.e. unwanted vs blocking)

  32. Unwanted Emission mask • P = 33 +(–23(dBc/Bref)) = 10 (dBm/200kHz)

  33. Interfering emission mask Unwanted: Rx bandwidth fIt fVr Calculate iRSS unwanted • iRSS unwanted calculate the interfering power received by the Victim receiver within its bandwidth • iRSSunwanted = P+Ge+Gr-L • iRSSunwanted = 10(dBm/200kHz)+11+9-(32.5+10log(32)+20log(1000)) • iRSSunwanted = -77.5dBm In this example there is no bandwidth correction factor to be applied to the calculation of the iRSS unwanted since the Vr bandwidth and the It reference bandwidth have the same value (i.e. 200 KHz).

  34. Calculate iRSS blocking (1/4)

  35. Receiver Mask Rx bandwidth Blocking: Rejection of the receiver fIt fVr Calculate iRSS blocking (2/4) • User-defined mode: • iRSS blocking (fit) = Pe+Ge+Gr-L-Att (fit) • iRSS blocking = 33(dBm)+11+9-(32.5+10log(32)+20log(1000))-40(dB) • iRSS blocking = -94.5dBm • The It bandwidth is not considered in the iRSS blocking calculation)

  36. Calculate iRSS blocking (3/4) • Sensitivity mode: • Attenuation(f) = block(f) [dBm] – sensvr [dBm] + C/(N+I) [dB] • Sensitivity = Noise Floor + C/(N+I) • Sensitivity = -110dBm + 16 = -94dBm • Attenuation (f ) = 40-(-94)+16= 150dB • iRSS blocking (fit) = Pe+Ge+Gr-L-Att (fit) • iRSS blocking = -54.5-150 = -204.5dBm

  37. Calculate iRSS blocking (4/4) • Protection Ratio: • Attenuation(f) = block(f) [dBm] + C/(N+I) [dB] + 3dB • Attenuation(f) = 40 +16 +3 = 59 dB • iRSS blocking (fit) = Pe+Ge+Gr-L-Att (fit) • iRSS blocking = -54.5-59 = -113.5 dBm

  38. Probability of interference (1/2) • For the unwanted mode, the C/I can be derived as: • dRSS/iRSS unwanted = -53.5-(-77.5) = 24dB • Since the resulting C/I is above the protection criteria (19 dB), the probability of interference is 0 • It is also possible to derive the (N+I)/N= -77.5-(-100)= 22.5 (since I>>N). Since the (I+N)/N which is obtained is above the protection criteria (3dB), the probability of interference is 1

  39. Probability of interference (2/2) • For the blocking mode, the C/I can be derived as: • dRSS/iRSS blocking = -53.5-(-113.5) = 60dB • Since the resulting C/I is above the protection criteria (19 dB), the probability of interference is 0 • It is also possible to derive the (N+I)/N= -113.5-(-100)= -13.5. Since the (I+N)/N which is obtained is below the protection criteria (3dB), the probability of interference is 0

  40. Thank you - Any Questions?

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