Definition

Microwave frequencies range from approximately 300 MHz to 300 GHz, with wavelengths from 1 meter to 1 millimeter. At microwave frequencies, PCB traces behave as transmission lines where impedance, loss, and phase are critical. Microwave PCBs typically use low-loss materials like Rogers or Taconic PTFE-based laminates with tight Dk tolerance. Applications include radar, satellite communications, cellular base stations, and automotive radar (77 GHz). Microwave design considers waveguides, transitions, and antenna integration. Material selection balances electrical performance with processability and cost.