Our test lab measures all customer antennas by exciting them with our swept VNA sources and observing their response with a quad-ridge antenna at the other end of our anechoic chamber, usually 12 feet away. This is called far field testing, because we observe your antenna’s actual performance from a significant distance.
Far field testing is an accurate and natural way to evaluate antennas. It makes makes no assumptions about their operation and involves no simulations or predictions. It also quantifies feed-line radiation and other unexpected distortions which happen near the antenna.
Smaller chambers sometimes use “near field scanning”. In this method, a probe (like this one shown) is scanned near and around the antenna under test. The probe results are run through a mathematical algorithm to predict the far field pattern of the antenna. This method may miss many real world antenna effects such as feed-line distortions. It can be less expensive, and does not require a large anechoic chamber. It is well suited to large aperture antennas that have challenging far field requirements.
Ready to get your antenna project underway … then contact us and let us help. A qualified antenna testing company will get your project on track.