摘要 |
This invention relates to an analog phase shifter for radio frequency signals that employs a hybrid coupler and biased varactor diodes at its reflection terminals. The diodes are operated so that the normalized reactance is unity (equals the coupler's input impedance) at an intermediate frequency which may be the geometric mean of the end frequencies of a broad bandwidth. The couplers are cascaded in tandem for a 360 DEG phase shift. A balanced configuration of hybrid couplers is used for the phase shifter.
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