Patent ID: 7282926

Claim:
An apparatus for characterizing a high-frequency device-under-test, comprising: a. a first electromagnetic waveguiding structure, which guides a first electromagnetic wave signal towards a first terminal of said high-frequency device-under-test and which guides a second electromagnetic wave signal away from said first terminal of said high-frequency device-under-test, b. a piece of conductive wire, said piece of conductive wire having a first end and a second end, and said piece of conductive wire being exposed to the electrical field and to the magnetic field of said first electromagnetic wave signal, and said piece of conductive wire being exposed to the electrical field and to the magnetic field of said second electromagnetic wave signal, and said piece of conductive wire having a length which is substantially smaller than one half of the wavelength of said first electro-magnetic wave signal, and said piece of conductive wire having a length which is substantially smaller than one half of the wavelength of said second electromagnetic wave signal, c. a second electromagnetic waveguiding structure, which is connected to said first end of said piece of conductive wire, whereby said second electromagnetic waveguiding structure senses said second electro-magnetic wave signal, d. a means for establishing a plurality of impedances at said terminal of said device-under-test, e. a means for determining the time domain waveform of the signal that is sensed by said second electromagnetic waveguiding structure, whereby said piece of conductive wire causes substantially no energy loss in said first and said second electromagnetic wave signals.