RF Directional Couplers and 3dB Hybrids OverviewApplication Note RF Directional Couplers and 3dB Hybrids Overview Directional Couplers For providing a sample of the power propagating in one direction on a transmission line. M560 V2.00 3dB Hybrids For dividing a signal into two signals of equal amplitude and a constant 90° or 180° phase differential. For quadrature combining or performing summation/differential combining. coupler”, “90° hybrid”, and “180° hybrid” is based on convention. However, the 90° and 180° hybrids could be thought of as 3 dB directional couplers. Despite these similarities, the parameters used to describe signal flow in directional couplers and the application, in actual use, is sufficiently different to warrant separate considerations. 180° Hybrids Functional Description A 180° hybrid is a reciprocal four-……