Highly Compact VHF/UHF Dual-Band/Dual-Function LTCC Circuits: Application to Avionic Systems

New architecture for a compact dual-band coupler filter suitable for avionic systems operating in the VHF 108-137 MHz and UHF 329-335-MHz bands is proposed. A systematic design methodology is presented, whereby, starting with a distributed branchline coupler, equivalent lumped-element models are generated and augmented to obtain the desired functionality. The resulting topology of interconnected inductors and capacitors is designed in an LTCC technology with a very small form factor. This circuit is fabricated and tested. Measured results are in close agreement with simulation and show that the circuit meets the required specifications.