Testing of electronic industries association land-mobile communication antenna gain standards at the national bureau of standards

The Electronic Industries Association has a published standard, EIA RS-329A, "Minimum Standards for Land-Mobile Communications Antennas," Dec. 1975. This standard details the minimum performance requirements and the test methods for evaluating the performance of fixed and base station antennas at frequencies from 25-1000 MHz. Also included in this standard are the specifications for a set of standard antennas for use in various frequency bands. The EIA Antenna Committee, TR8.11, requested the National Bureau of Standards to calibrate the gain of some of these antenna standards. Two antennas were calibrated in the 450-512-MHz band, and two antennas in the 800-900 MHz band. This paper describes in detail the techniques used throughout the measurement program, the results, and the measurement uncertainties. Two basic methods of measuring the gain of the EIA antennas were employed during this calibration. The three-antenna technique was used at some frequencies, and the standard field technique was used at other frequencies. Both techniques are described. The NBS antennas used for the measurements were standard-gain pyramidal horn antennas. The antenna range used for the measurement is described. This is a vertical range using nonmetallic towers and hardware, thus providing essentially free-space conditions in which reflections and multipath problems are minimized. The measurements were made in terms of absolute power gain, i.e., referenced to an isotropic radiator. These results are discussed and also compared to the gain figures listed in EIA standard RS-329A.