1. Beamformer Feeding Board Design and IC Package EM Simulation
Presenter: Tailei Wang
Supervisor: Aurore SavoyNavarro
Steve Torchinsky
Sangitiana Rakotozafy Harison

2. Outline
Introduction of the Square Kilometer Array (SKA) and Octagonal Ring Array (ORA);
Printed Circuit Board (PCB) design in Altium;
Board Electromagnetic (EM) Simulation in HyperLynx;
Integrated Circuit (IC) Package EM Simulation in ADS and HyperLynx;
Future Work and Acknowledgement.
1) Why this board is needed?
2) Explain the design process in Altium and HyperLynx
3) The influence of package, significantly affect the IC performance
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3. SKA and ORA Collecting area: 1 million m2
The Square Kilometre Array (SKA) will be the largest radio astronomy facility ever built with a collecting area equivalent to a million square meters. The SKA will combine the signals received from thousands of small antennas spread over a distance of several thousand kilometers to simulate a single giant radio telescope capable of extremely high sensitivity and angular resolution.
Octagonal Ring Antenna (ORA) [1] is a kind of antenna technology which can be used in SKA. Between the ORA and beamformer board, a feeding board is needed to feed the LNA board in ORA and connect with the beamformer board.
Spread over thousand kilometers
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4. Introduction of the Board
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5. Step 1: Board Design in Altium
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6. Step 2:Layer Stack of the Board
The thickness will make sure the board is strong enough, not easy to be bended.
Total Thickness: 1.59mm
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7. Step 3: EM Simulation with Hyperlynx
The overall insertion loss is less than 0.15dB which satisfied the requirement in engineering application.
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8. The Influence of Metal Via
With metal via
Without metal via
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9. The Influence of Dielectric Constant Variation
As we know, the dielectric of FR4 is not stable, it varies from 3.8 to 4.3. The simulation result shows that the D-value caused by variation of dielectric is less than 0.08 dB.
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10. Step 4: Line Simulation with Hyperlynx
This simulation is used to select the component value. Comparing the S11 and S33 curve, we should choose 100pf capacitor.
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11. Step 5: Prototype of the Board
Size: 162mm*41.3mm
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12. Package EM simulation in ADS
Why do we need to do the simulation?
IC characterization is no longer limited to the IC itself, as we know, ICs need to be packaged, so the packaging and bondwire will affect the performance.
Accurate prediction of the affects of package and bondwire at high frequency is increasingly important as ICs continue to shrink and to operate at higher frequencies.
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13. An Example of Filter designed for 7GHz-9GHz
This is used to show the importance of package EM simulation.
This is the layout and circuit in ADS without packaging.
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14. View of the Filter with Package in ADS
Packaging the circuit
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15. Simulation Results
Obviously, there is a frequency shift after packaging the circuit and the insert loss is increased at the same time.
In the 1GHz-12GHz band, the noise figure is increased.
After packaging, the filter will not satisfy the requirement again.
It’s very important to predict the package board and bondwire effects on the RF module before manufacture.
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16. Bondwire Length Influence
This is a symmetric structure, so we will just concern the results of port 1,17 and port 2,18.
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17. The change of bondwire length doesn’t significantly affect the return loss.
However, the insertion loss will increase with longer bondwire length.
However, the parasitic effect, especially the inductive effect, of adding bondwire can’t be ignored.
This may affect the circuit while here is just a model without actual circuit.
At the same time, the S parameter files with different bondwire length will be exported and used in Cadence IC design.
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18. Future Work Manufacture the board;
Connect with the beamformer board and Antenna and measurement;
Further EM simulation about QFN package in HyperLynx, like adding IC and other package types;
Writing HyperLynx Package EM simulation manual;
Learn LNA and filter design.
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19. Acknowledgement
This work is supported by EU FP7-PEOPLE-2012-ITN project nr317446, INFIERI, “Intelligent Fast Interconnected and Efficient Devices for Frontier Exploitation in Research and Industry”.
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20. Thank YOU
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