Alumina ceramic pcb, ceramic circuit board substrate
RF PCB Layout: Interconnect Losses
Your trace geometry and layer stack will have a major effect on signal integrity as you route high frequency analog signals throughout your board. Newer designers will likely default to a microstrip geometry, possibly with guard vias to provide isolation between different circuit blocks and to suppress radiated emissions. The question of which trace geometry to use is about more than isolation; it is also about avoiding losses due to dielectric absorption, roughness losses, and scattering from your PCB substrate. The alternative to using microstrip transmission lines is to use stripline transmission lines. Routing striplines on a dedicated interior layer [...]