What are the benefits of integrating EBG structures into multilayer RF ceramic packages?
• Parasitic cavity modes internal to the shielded package may be suppressed over the frequency range of the fundamental stopband. • Crosstalk between internal transmission lines can be suppressed. • For packages with integrated antenna elements, external EBG structures can be used to help control the pattern characteristics: beamwidth, side lobe level, and front-to-back ratio. • For packages with an integrated diversity antenna system, an external EBG structure can reduce the mutual coupling between antenna elements. • Q: What are cavity modes? A: Many RF packages are shielded for EMI and EMC reasons. Shielded packages contain metalized cavities that resonate at a multitude of discrete frequencies. Resonant modes, or cavity modes, can be excited by interconnects, such as bond wires, or by transmission lines, such as microstriplines, within the RF package. • Q: Why are cavity modes a problem? A: Cavity modes are excited with RF power that would otherwise be used to perform a useful func
