| 摘要 |
An electromagnetic field sensing apparatus which detects an incoming electromagnetic field and provides an RF electrical signal indicative of the strength of the field. The electromagnetic field sensing apparatus includes a metallic antenna which intercepts the incoming planar electromagnetic wave and provides an electrical signal indicative of the strength/intensity of the field. A microwave amplifier receives the electrical signal, amplifies the signal by a factor of at least 100 and then supplies the amplified signal to an electro-optic modulator. A first light source located along a first optical path transmits polarized laser light through the electro-optic modulator. The electro-optic modulator, in response to the amplified electrical signal modulates the polarized light when the metallic antenna detects the incident electromagnetic wave. A photodetector located along the first optical path detects the modulated light as it exists from the electro-optic modulator. In this manner incident planar wave electromagnetic fields are detected and measured. A second light source, located along a second optical path, transmits a monochromatic laser light beam along the second optical path to a photovoltaic cell which then provides a DC bias voltage to the microwave amplifier.
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