Definition

Radio Frequency (RF) refers to electromagnetic signals in the frequency range of approximately 3 kHz to 300 GHz. RF PCB design requires controlled impedance transmission lines, low-loss materials (PTFE, Rogers, high-frequency laminates), careful ground plane design, and attention to electromagnetic coupling. As frequency increases, wavelength decreases, making PCB features electrically significant (a trace stub becomes a resonator). RF circuits include filters, amplifiers, mixers, and antennas. Millimeter-wave applications (>30 GHz) demand the tightest material and fabrication tolerances.