| 摘要 |
<p>A modulator system (30) for converting a three-channel input microwave signal to a single-channel output microwave signal is formed of two (upper and lower) microwave sections which are joined together by a hybrid divider (94) at their inputs and by a hybrid combiner (96) at their outputs. Each of the microwave sections includes a pair of couplers (82 and 84, 88 and 90) which are joined by a Faraday rotator (86, 92). First and second microwave input signals (48, 52) are applied to a first port of the input coupler (82, 88) in each of these sections. A third microwave signal (50) is directed by the hybrid divider (94) to a second imput port in the input couplers (82, 84) of each of the microwave sections. Polarization of the third signal is vertical and is maintained through the two sections. Polarization of the first and second signals is horizontal and is maintained through the two sections. With activation of the rotator, a shift in polarization occurs resulting in appearence of the signals in both the horizontal and vertical components of an output coupler in each of the sections. The vertical component of the output couplers in each of the sections is combined by the hybrid combiner to produce the single-channel microwave signal (54). Synchronous detectors are utilized for subsequent extraction of the first and second input signals, the synchronous detectors and the Faraday rotators being driven by common sources of modulation signals wherein the rotator in one section is modulated at a rate different from the rotator in the second section. </p> |
