Quantifying Phase Velocity Shifts and Resonance Variations in Heterogeneous Glass Weave Anisotropic Substrates
Quantifying phase velocity shift in glass weave substrates requires mapping fiber pitch against trace angle to control differential skew.
Millimeter Wave Radar Substrate
Laminate Material
Specialized circuit platform provides the low loss characteristics required for high frequency automotive and industrial sensing systems. Choosing a millimeter wave radar substrate involves selecting materials with a very stable dielectric constant and a low dissipation factor at frequencies above 24 GHz. These substrates often use ceramic-filled PTFE or thermoset resins to minimize signal attenuation.
The copper surface must be exceptionally smooth to prevent skin effect losses.
Signal Transmission
Performance of the radar sensor depends on the phase stability of the signal as it travels through the antenna array. Because a millimeter wave radar substrate has a highly controlled thickness, the phase velocity remains consistent across the entire board. Any variation in the material properties would cause the radar beam to wander or lose focus.
Fabricators must use precise etching techniques to maintain the exact trace widths required by these high frequency designs. High frequency signals react poorly to even minor deviations in the dielectric interface.
Environmental Durability
Exposure to moisture and temperature fluctuations must not change the electrical properties of the base material. A high quality millimeter wave radar substrate maintains its performance over the life of the vehicle. Rigorous testing in thermal chambers ensures that the sensor remains accurate from sub-zero temperatures to the heat of the engine bay.