| 摘要 |
<p>Apparatus for controlling the phase of an amplitude-modulation signal carried by light, for example a frequency control signal for operating one module of a phased-array radar antenna, comprises: an electro-optic TE-TM converter (12) for splitting the amplitude-modulated, plane-polarised light (at 10) into orthogonally-plane-polarised portions in a controlled amplitude ratio; a birefringent waveguide (13) for introducing a relative delay between the two portions equal to a quarter-cycle of the amplitude modulation period; and a light detector (14) for producing a signal which is a vector combination of the signals carried by the two portions, phase-shifted in accordance with the said amplitude ratio.</p> |
