Modeling of 24 GHz RxTx Filters on LTCC - Empire

<strong>Modeling</strong> <strong>of</strong> <strong>24</strong> <strong>GHz</strong><strong>RxTx</strong> <strong>Filters</strong> on LTCCAndreas Lauer, IMST, Germany

Purpose• <strong>RxTx</strong> Module on multi-layered LTCC• Specifications:– f 0 =<strong>24</strong> <strong>GHz</strong> ± 0.4 <strong>GHz</strong>– 5 pole Chebychev– 0.02 dB ripple– Attenuation > 70 dB at ± 3 <strong>GHz</strong>• Design including 3D coupling effects

Outline• 3D Design Tool: EMPIRE• Microwave filter theory• Design steps• Results

Design examples• Antennas• MEMS switches• Multi-layeredcircuits

New features• Advanced modeling• Direct field animation• 3D radiation pattern

LP Filter PrototypeC1´=1.3745C2´=1.3745L1´=0.99844L2´=1.8283L3´=0.99844• Obtaining Land C values• Normalized toZ 0 =1 and ω=1

BP Filter• LP to BPtransformation• Series andparallelresonators

Microwave Filter• Series and parallel resonators @ <strong>24</strong> <strong>GHz</strong>:• Not properly feasible• Using inverters instead

Realisation• λ/2 resonators• Inverters: capacitivecoupling + missingline length

Design• Inverter design with 3D EM field solver:EMPIRE• Widths and Gaps are optimized• < 10 min on PC

BP FilterField @ passfrequency

BP Filter resultsSimulation vs.on-chipMeasurementsNo tuningnecessary

Conclusion• BP Filter:– Five pole <strong>24</strong> <strong>GHz</strong> <strong>RxTx</strong> Filter– Excellent agreement without tuning• LTCC:– High volume applications– Reliable technology• EMPIRE:– Design tool for all passive structures– Suitabe also for HQ structures

Visit usAt Booth no. 668(Hall Enear beverage area)www.empire.dewww.ltcc.dewww.imst.de