The selection of a substrate material is a balance between the required electrical, mechanical, and environmental performance required by a design versus economic constraints. Generally, if one has the available design volume to use air as a substrate for a microstrip antenna, this is a good choice. The antenna efficiency is high and the gain is maximized as is the impedance bandwidth of a conventional microstrip antenna. The surface wave loss when air is used as a substrate is minimal. When a dielectric substrate is selected, one is often interested in a material with the lowest loss tangent available. This Appendix discusses: microstrip antenna and transmission line substrates, metal cladding, dielectric materials, radome materials, water absorption, dielectric films, passive intermodulation, solder masks, and conformal coatings.

Chapter Contents:

• A.1 Microstrip antenna/transmission line substrates
• A.2 Metal cladding
• A.3 Dielectric materials
• A.3.1 Plastics
• A.3.2 Ceramics
• A.3.3 Glass transition temperature (Tg)
• A.3.4 Composite dielectric substrates
• A.3.5 FR-4
• A.3.6 Fiberglass
• A.3.7 Dielectric foam
• A.4 Radome materials
• A.5 Water absorption
• A.6 Dielectric films
• A.7 Passive intermodulation
• A.8 Solder mask and conformal coatings
• References

Inspec keywords: microstrip antennas; dielectric materials; substrates

Other keywords: solder masks; dielectric films; passive intermodulation; substrate material; metal cladding; microstrip antenna substrates; water absorption; conformal coatings; transmission line substrates; dielectric materials; radome materials

Subjects: Single antennas; Dielectric materials and properties