Planar/Cylindrical Near Field Range

The Planar/Cylindrical Near Field Range consists of a 20’ x 10’ x-y scanner for planar near field measurements, and an azimuth turntable used in conjunction with the 10’ vertical scanner for cylindrical near field measurements. The frequency of operation extends from 1120 MHz (WR650 probe) to 40 GHz (WR28 probe). The RF system employs an Agilent PNA receiver in a remote mixer configuration.

Spherical Near Field Range

The Spherical Near Field Range at GTRI is a recently acquired antenna measurement facility supported primarily by Nearfield Systems, Inc. (NSI) positioners and software. The positioning system is an ‘L’ bracket, roll-over-azimuth style, large enough for antennas that would fit within a horizontal cylinder 12 ft. long by 8 ft. in diameter. The rotary stages are the largest offered by NSI with a 10,000 lb. vertical load capacity and a 2,500 ft-lb. bending moment. The frequency of operation is limited at the low end to 1120 MHz (WR650 probe), while the high end is yet to be determined. System validations on standard gain horns have been performed through Ku-band (18 GHz). All EMTEF indoor ranges use Agilent PNA receivers in a remote mixer configuration.

Anechoic Chamber

The Shielded Antenna Chamber is an instrumented chamber suitable for indoor testing of electrically small to medium-sized antennas at frequencies from 200 MHz to 110 GHz. The chamber is 20 x 36 ft. in size, and has a combination of 24" and 36"absorber fully covering the shielded walls, ceiling, and doors. The RF system employs an Agilent PNA receiver. The positoner is a dielectric roll-over-azimuth style.

Outdoor Far Field Range

The far-field antenna test range consists of two signal towers, source and receive, situated 1300' apart. It features a heavy-duty, three-axis positioner, capable of handling antennas up to 30' in diameter and weighing up to 30,000 pounds. It ensures extreme mechanical precision through its exceptionally massive towers and stable platforms at both ends. RF is provided by an 8530-based remote mixer system.

Turntable Range

The large turntable range is comprised of an elevated platform built onto the side of the source tower of the outdoor far field range, and a heavyweight turntable located approximately 150 ft. from the base of the tower. The platform can be elevated over a distance of approximately 90 ft. above the tower base. This allows testing to be performed on tank-sized targets at elevation angles up to 32 degrees and is suitable for on-vehicle antenna testing and specific RCS applications. The turntable can support a vertical load in excess of 200,000 pounds (100 tons).