Electronic phase shifting circuit for use in a phased radar antenna array

A phase bit circuit for receiving an input signal and producing an output signal which is selectively shifted in phase by a first predetermined amount or a second predetermined amount relative to the input signal, comprising;

• input terminal means for inputting the input signal;
• output terminal means for outputting the output signal;
• first transmission line means coupled between the input and output terminal means;
• a first diode coupled between the first transmission line means and the input terminal means;
• a second diode coupled between the first transmission line means and the output terminal means;
• second and third transmission line means connected in series with each other between the input and output terminal means, the second and third transmission line means defining a junction therebetween;
• a third diode coupled between said junction of the second and third transmission line means and ground;
• and
• biasing means coupled to the first, second and third diodes for selectively forward biasing the first, second and third diodes to cause substantially all of the input signal to propagate from the input terminal means through the first transmission line means to the output terminal means to constitute the output signal which is shifted in phase relative to the input signal by the first predetermined amount;
• or reverse biasing the first, second and third diodes to cause a first portion of the input signal to propagate from the input terminal means through the first transmission line means to the output terminal means and a second portion of the input signal to propagate from the input terminal means through the second and third transmission line means to the output terminal means, said first and second portions of the input signal combining at the output terminal means to constitute the output signal which is phase shifted in phase relative to the input signal by the second predetermined amount.