Patent ID: 6215448
Filing Date: 2001-04-10
Classification: H01P,H04B

Abstract:
An antenna coupler for coupling the antenna of a device under test to an instance of test equipment, the antenna coupler comprising:an inner cylinder having inner and outer surfaces of conductive material and into which at a first end thereof an antenna of a device under test is insertable for a selected depth along the axis of the inner cylinder, the inner cylinder having constant inner and outer diameters along a length at least equal to the selected depth starting at the first end, and thereafter for a second length the outer diameter of the inner cylinder tapering to a first selected diameter, the inner surface of the inner cylinder forming when the antenna is inserted therein an unterminated first coaxial transmission line of characteristic impedance Z.sub.0in ;an outer cylinder having an inner surface of conductive material and having a first end thereof disposed generally opposite the first end of the inner cylinder and having the same axis as the inner cylinder, the outer cylinder containing the inner cylinder and having a constant inner diameter opposite the region of constant outer diameter for the inner cylinder and for the same length, and thereafter for the second length the inner diameter of the outer cylinder tapering to maintain a constant characteristic impedance Z.sub.0out as the outer diameter of the inner cylinder tapers to the first selected diameter, the inner surface of the outer cylinder forming with the outer surface of the inner cylinder a second coaxial transmission line also of characteristic impedance Z.sub.0out ; andan RF connection for conveying RF power coupled between the antenna and an instance of test equipment, the RF connection located at a distal end of the second coaxial transmission line opposite the first end.