Patent ID: 6975111
Filing Date: 2005-12-13
Classification: G01R

Abstract:
1. Apparatus for deriving an indication of at least one of a magnetic and electric field component of an electromagnetic field from a device-under-test, the apparatus comprising an electromagnetic field detector probe including a conductor shaped as a loop and having opposite first and second ends, the loop having a portion adapted to be electromagnetically coupled with the device-under-test, the probe being arranged so that it does not include a shield that affects the electromagnetic field coupled between the device under test and the loop portion, the loop being arranged so that (a) in response to the magnetic field component a first current component I m flows from the first end to the second end and (b) in response to the electric field component second and third equal amplitude current components I e flow in the same direction through the first and second ends so that currents I 1 and I 2 flowing through the first and second ends respectively have values directly proportional to (I e +I m ) and (I e −I m ), and circuitry connected to be response to the currents I 1 and I 2 for deriving at least one output signal having a value commensurate with the at least one of the magnetic and electric field components, and a scanner for moving the detector probe relative to the device-under-test in a region adjacent the device-under-test so that as the probe moves in the region, the loop portion is coupled with different electric and magnetic field components derived by the device under test, causing the currents I 1 and I 2 change, and the values of (I e +I m ) and (I e −I m ) to change, the circuitry being arranged to respond to the values of I 1 and I 2 for deriving an indication of the distribution of the electromagnetic field of the device-under-test in the region.