Special shielding material designed for microwave frequencies
Miniature coax used for low power applications
Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies✓Bonne réponse
Explication
Microstrip is a printed-circuit transmission line: a precisely dimensioned trace running above a ground plane on the other side of the board, whose width and substrate thickness set its characteristic impedance. It is how constant-impedance interconnects are made on microwave circuit boards, without any coaxial cable involved.