Refractive compact range
A radio-frequency-device test range (the Refractive Compact Range) includes a physical space having a source zone for placing an antenna or array of antennas, and a test zone for placing a sensor or other device to be tested. A lens and an apodizer are placed in the physical space between the source zone and the test zone. The lens serves to collimate radiated energy emanating from the antenna toward the test zone. The lens may have a surface treatment, such as an anti-reflective coating or a surface pattern, on one or both surfaces. The apodizer functions to keep energy from diffracting off the edge of the lens and getting into the field of view (the test zone). The sensor or other device to be tested may be placed on a moveable mount to allow it to be moved, to simulate relative movement of the device and a radio frequency source, such as radiated by an antenna.
1. A radio frequency test range comprising:
a physical space that includes a source zone, and a test zone for placing a device to be tested;
an aspheric lens between the source zone and the test zone;
an apodizer placed between the source zone and the lens; and
an array of antennas in the source zone;
wherein the lens collimates energy emitted by the array of antennas into the test zone;
wherein the apodizer is located relative to the lens such that the apodizer prevents radiation emitted from the source zone from reaching an edge of the lens; and
wherein the apodizer at least reduces destructive interference patterns in the energy reaching the test zone by removing the edge of the lens as a re-radiating surface.
2. The test range of claim 1 , wherein the lens includes a dielectric material.
3. The test range of claim 1 , wherein the lens includes a composite material.
4. The test range of claim 1 , wherein the lens includes a plastic material.
5. The test range of claim 1 , wherein the lens has an antireflection surface treatment on at least one surface.
6. The test range of claim 5 , wherein the surface treatment includes a surface coating.
7. The test range of claim 6 , wherein the surface coating includes layers of dielectric materials with different indices of refraction and thickness.
8. The test range of claim 5 , wherein the surface treatment includes a surface pattern.
9. The test range of claim 1 , wherein the apodizer is a resistance card fence apodizer That includes resistive sheets.
10. The test range of claim 1 , wherein the apodizer is substantially radially symmetric.
11. The test range of claim 1 , further comprising a movement platform configured to allow movement of a device in the test zone.
12. The test range of claim 1 , wherein the lens is a multipart lens with different parts having different respective indices of refraction.