| 摘要 |
PHASE CONTROL CIRCUIT A controllable phase shifting circuit comprises first and second differential amplifiers, each providing antiphase outputs and supplied respectively with first and second alternating reference signals which are in a first predetermined (e.g., quadrature) phase relation. A third signal, which is a fractional part of one of the first two signals, is combined with the other of the first two signals at its respective amplifier input to produce a fourth signal with a phase different from that of the first, second or third signals. A third amplifier provides differential gain control inputs to the first and second amplifiers. A combining circuit sums signal components from the first and second amplifiers to produce an output signal with a desired phase which is controllable in accordance with the gain control input signals. |
