Digital phase shifter apparatus

Claim 1

A digital phase shift apparatus comprising in combination: a first and second field effect transistor, said first and second field effect transistor respectively including a single gate, a source and a drain, a first transmission line operatively connected to said source of said first field effect transistor, said first transmission line receiving an RF input signal, a second transmission line operatively connected to said drain of said first field effect transistor, said second transmission line providing an RF signal output, a third transmission line operatively connected between said source of said first field effect transistor and said source of said second field effect transistor, a fourth transmission line operatively connected between said drain of said first field effect transistor and said drain of said second field effect transistor, a first means for biasing, said first biasing means operatively connected to said first transmission line, a second means for biasing, said second biasing means operatively connected to said second transmission line, a first signal switch means operatively connected to said gate of said first field effect transistor, a second signal switch means operatively connected to said gate of said second field effect transistor, said first signal switch means controlling the operating state of said first field effect transistor, said second signal switch means controlling the operating state of said second field effect transistor, the operating states of said first and second field effect transistors being mutually exclusive, said phase shift apparatus providing a phase-shifted RF signal at said RF signal output when said first field effect transistor is in the OFF operating state and said second field effect transistor is in the ON operating state, the field effect transistor in the ON operating state functioning as both a signal path length switch and a signal amplifier.