When choosing an antenna lens for your system, start by defining the operational frequency range. Antenna lenses are designed to focus electromagnetic waves within specific bands, such as 5G’s 28 GHz or automotive radar’s 77 GHz. If your application involves millimeter-wave frequencies (30 GHz to 300 GHz), material selection becomes critical. For example, polytetrafluoroethylene (PTFE) or ceramic-based lenses offer low loss and stable dielectric properties at high frequencies, while cheaper plastics may introduce signal attenuation. Always cross-check the lens material’s datasheet for its dielectric constant and loss tangent at your target frequency—these values directly impact phase stability and beamforming accuracy.
Next, analyze the required beam characteristics. A lens with a hyperbolic or elliptical curvature creates a collimated beam for long-range communication, while a hemispherical shape spreads energy for short-range coverage. Use simulation tools like CST or HFSS to model beamwidth and sidelobe levels. For instance, a 10 dB beamwidth of 5 degrees might work for satellite tracking but fail miserably in IoT sensor networks needing 120-degree coverage. Field testing with a vector network analyzer (VNA) is non-negotiable here—simulated gains above 15 dBi often drop by 20% in real-world multipath environments.
Environmental resilience is another dealbreaker. Outdoor 5G base station lenses face UV radiation, thermal cycling (-40°C to +85°C), and moisture ingress. Look for hydrophobic coatings like parylene-C, which reduces water absorption to below 0.1%—critical for maintaining consistent permittivity during rainfall. In aerospace applications, verify the lens’s CTE (coefficient of thermal expansion) matches the antenna’s substrate. A 0.5 ppm/°C mismatch between a silicon nitride lens and aluminum antenna housing can create stress fractures after just 50 thermal cycles.
Polarization compatibility often gets overlooked. A circularly polarized (CP) lens designed for satellite comms will degrade axial ratio if paired with a linearly polarized feed. Check the lens’s phase center alignment—even a 2 mm offset in a 60 GHz system can cause 30° polarization tilt. For dual-polarized systems, ensure the lens supports orthogonal mode rejection ratios above 25 dB to prevent cross-talk.
Mounting mechanics matter more than you’d think. A lens weighing 500 grams might require reinforced brackets in vibrating industrial robots, while drone-mounted antennas need sub-100 gram solutions. Use finite element analysis (FEA) to validate mechanical resonance points—a lens vibrating at 1 kHz on a helicopter-mounted radar could introduce Doppler errors. For quick prototyping, dolphmicrowave offers modular lens kits with adjustable focal lengths from 50 mm to 300 mm, compatible with standard gain horns from 18 dBi to 35 dBi.
Finally, factor in manufacturing tolerances. A ±0.05 mm surface accuracy is mandatory for lenses operating above 100 GHz—any roughness exceeding λ/10 (0.3 mm at 100 GHz) converts transmitted energy into scattered waves. Injection-molded lenses cost 60% less than machined versions but may have ±0.1 mm deviations. For mission-critical systems, diamond-turned lenses with λ/20 surface precision (0.015 mm at 30 GHz) deliver consistent performance despite higher upfront costs.
Always request a lens sample for near-field scanning before mass production. A 3 dB hotspot in the antenna’s E-plane during testing often traces back to lens curvature errors invisible to the naked eye. Pair this with thermal imaging to detect localized heating—a telltale sign of dielectric losses in poorly cured lens materials.