| 摘要 |
A diversity combiner for adding, before detection, two or more received radio signals having defined carrier waves of the same frequency contains for each of the radio signals (S1; S2) a phase shifter (4) for dividing the radio signals into a sub-signal (S1i; S2i) forming an in-phase signal and a sub-signal (S1q; S2q) forming a quadrature signal, for each of the sub-signals a phase-sensitive detector (2) controlled by a reference signal (A) common to all the detectors, and having an output signal of zero frequency direct-voltage connected to a modulation input of a subsequent modulator (Z2-Z5) for converting the radio signal to an alternating voltage signal (C) of the same phase angle as that of the reference signal (A), and for all the radio signal together an adder (Z8) for adding the cophasal alternating voltage signals from all the means for conversion (Z2-Z5) to a sum-signal (E) in which the received radio signals are added, the sum signal (E) being connected to the control inputs of the phase-sensitive detectors (2) such as to act there as the common reference signal for all the detectors. |
