A phase shifter is provided. The phase shifter includes a first phase shifter that is continuously adjustable within a range of 0 degrees to 90 degrees, two 4-way switches each configured to selectively switch on one of a capacitance, an inductance, an open circuit, and a short circuit under control of a control voltage, and a bridge. A first input end and a first output end of said bridge are respectively connected to a first 4-way switch of the two 4-way switches. A second input end of said bridge is connected to an output end of said first phase shifter or a second output end of said bridge is connected to an input end of said first phase shifter.