Depending on the size of the test target

Depending on the size of the test target, the frequencies to be used, and other test requirements, measurements may be made in indoor test facilities or on outdoor ranges. In general, the outdoor facilitates are required when test target are too large to be measured indoors. A disadvantage of such facilities is easily influenced by weather and wind conditions, and consequently it is difficult to get high resolution and accurate results. On contraries, the indoor facilities such as anechoic chambers whose interior walls are covered with high-quality radar-absorbing material offer the attractive advantage of being independent of weather conditions and therefore more productive testing 24.