COMPACT RANGE ILLUMINATORS, TEST CHAMBER ANTENNAS

Antennas for RF Production and Flight-line Test Chambers

Modern RF test equipment utilizes computer-driven vector network analyzer-based data collection systems. These systems are often integrated into a dedicated test nacelle or test chamber to perform on-line validation of installed electronic equipment. For example, a complete Unpiloted Airborne Vehicle may be placed in such a test chamber. All of its radiating systems can then be checked for performance and for electromagnetic susceptibility.

Seavey Engineering provides specialized antennas for use in these test chambers. Antennas of this type must have very specific characteristics such as shaped beams, gain leveling, specific polarizations and controlled phase centers.

For example, the following complement of antennas has been developed to test the forward section of a military aircraft in a test nacelle.

Model 9739-880 0.7 - 0.8 GHz Monopole	Model 9739 Horn Family	Models 9739-810 and -830 Scalar Horns

Compact Range Dual-Beam Polarization-Selectable Illuminators

These compact range illuminators consist of two feeds placed side-by-side about the reflector focus. They create spatially isolated beams with different polarizations. By switching between their ports, the data collection rate can be doubled. As an alternate to dual-polarized illuminators, they offer superior cross-polarization performance (35 - 40 dB) and are useful when measuring a full polarization matrix. They interface with a Scientific Atlanta Model 5754 Compact Range feed positioner.
		Model 9619-800 X-band horn pair
Antenna Model Frequency GHz Illuminator Type Polarization 9619-800 9.0 - 11.0 Scalar Horn Pair Selectable Circular 9569-800 26.5 - 40.0 Scalar Horn Pair Rotatable Linear
		Model 9569-800 Ka-band Horn Pair

Illuminators for Compact Ranges

Offset serrated-rim or rolled-rim compact range reflectors require specialized feed systems. These feeds (illuminators) should provide wide frequency coverage in standardized frequency bands. They must have controlled phase centers and excellent cross-polarization. Their patterns must be wide to that the edge amplitude taper on the reflector is minimized. Illuminators should also be compatible with and mount to industry-standard polarization positioners such as Orbit-F/R and Scientific-Atlanta units.

Seavey Engineering has available a complete line of illuminators for these purposes from 1 to 100 GHz.

Model 9401-801 1 -2 GHz Quad Ridged Horn	Model 9401-851 Switched, 4-state Polarization Horn	9401-803 4 -8 GHz Quad Ridged Horn
Model 9401-811 X-band Selectable Circular Scalar Horn	Models 9401-813, -814 K and Ka-band Linear Rotatable Scalar Horns	Model 9231-800 Ka-band Orthogonal Linear Scalar Horn