High-performance probe for near-field antenna measurement

Abstract

Provided herein are high-performance, compact probes for use in near-field antenna measurement, such as over-the-air antenna measurements. In particular, the probes herein simplify detection by mixing the near-field radio frequency (RF) signal with a local oscillator (LO) right at the probe plane.

1 . A probe comprising:
 (a) a top layer comprising an antenna for transducing an electric or magnetic field;   (b) a bottom layer comprising an aperture; and   (c) a middle layer comprising a ground plane for the antenna.   
     
     
         2 . The probe of  claim 1 , wherein the aperture is oriented at an angle of 0-90 degrees. 
     
     
         3 . The probe of  claim 2 , wherein the aperture is oriented at an angle of 30-60 degrees. 
     
     
         4 . The probe of  claim 2 , wherein the aperture is oriented at an angle of 45 degrees. 
     
     
         5 . A probe comprising an RF antenna, a mixer at the probe plane, a waveguide coupled to an aperture. 
     
     
         6 . The probe of  claim 5 , wherein the waveguide is a substantially-rectangular waveguide. 
     
     
         7 . The probe of  claim 6 , wherein the waveguide is a rectangular waveguide. 
     
     
         8 . The probe of  claim 5 , wherein the waveguide is a coaxial and/or coplanar waveguide. 
     
     
         9 . The probe of  claim 5 , wherein the waveguide is a substrate-integrated waveguide (SIW) 
     
     
         10 . The probe of  claim 5 , wherein the RF antenna is a slot or slot-like antenna. 
     
     
         11 . The probe of  claim 10 , wherein the slot is oriented at an angle of 45 degrees. 
     
     
         12 . The probe of  claim 5  wherein a local oscillator (LO) signal is fed through a rectangular waveguide, coupled to a slot or slot-like antenna, and then transferred to the mixer for mixing with an RF signal from the RF antennae to generate an output intermediate frequency (IF) 
     
     
         13 . A method of measuring near-field radiation comprising mixing a near-field radio frequency (RF) signal with a local oscillator (LO) signal to generate an output intermediate frequency (IF). 
     
     
         14 . The method of  claim 13 , wherein the RF and LO signals are mixed directly on a probe. 
     
     
         15 . The method of  claim 13 , wherein the IF is used for near- to far-field calculation.