When I was in the antenna business, the largest "piece" of test equipment was the RF test chamber. It had a source horn and a network analyzer. Everything else was custom, and was modified frequently. There has been an issue for a long time in the antenna business that the gain and pattern tests are not standard, and often published specs / test results are not believeable. We went through a test of 5 or 6 global sites, sending around a set of carefully designed and fabricated test antennas. We found 1 dB from the lowest reported gains to the highest. 1 dB is a large error for most antennas.