A phase shifter has a chamber with a holding space, a first feeder unit and a second feeder unit at the sides of the holding space, and at least one reversely configured electric regulation unit. The regulation unit contains a first coupling set with a movable and a fixed coupling, and a second coupling set with a movable and a fixed coupling. A sync linkage mechanism is used to link the respective movable couplings. A push-pull unit is linked to a driven connection of the sync linkage mechanism. A cover plate seals the holding space. The phase shifter configuration makes it possible to reduce markedly the volume and space of the phase shifter, cut down the manufacturing cost and improve the mating accuracy with higher applicability.