Antenna unit with phase-shifting modulator, and related antenna, subsystem, system, and method

An antenna, comprising:

• control nodes;
• and
• an array of antenna units each including
• a respective coupler having a first input-output port, a second input-output port, and a first coupled port,
• a respective first phase-shifting modulator coupled to the first coupled port and to a respective at least one of the control nodes, and
• a respective first antenna element coupled to the respective first phase-shifting modulator.

A radar subsystem, comprising:

• an antenna, including,
• control nodes;
• an array of antenna units each including
• a respective coupler having a first input-output port, a second input-output port, and a coupled port,
• a respective phase-shifting modulator coupled to the coupled port and to a respective at least one of the control nodes, and
• a respective antenna element coupled to the respective phase-shifting modulator;
• a transceiver circuit configured to generate, and to provide to the antenna, a transmit reference wave, and to receive, from the antenna, a receive reference wave;
• a beam-steering controller circuit configured to generate, on the control nodes, respective control signals to cause the antenna
• to generate, with each respective antenna element, a respective transmit signal in response to the at transmit reference wave,
• to form, from the transmit signals, a transmit beam pattern including a main transmit beam,
• to steer the main transmit beam,
• to receive, with each respective antenna element, a respective receive signal,
• to form, from the receive signals, a receive beam pattern including a main receive beam,
• to steer the main receive beam, and
• to generate, in response to the main receive beam, the receive reference wave;
• and
• a master controller circuit configured to detect, in response to the receive reference wave from the transceiver circuit, an object.

A method, comprising:

• generating, in response to an input signal, a first intermediate signal on a first coupled port of a coupler and an output signal on an output port of the coupler;
• shifting a phase of the first intermediate signal;
• and
• radiating a first transmit signal with a first antenna element in response to the phase-shifted first intermediate signal.

A method, comprising:

• generating, in response to a first receive signal, a first intermediate signal with a first antenna element;
• shifting a phase of the first intermediate signal;
• and
• generating, in response to an input signal on an input port of a coupler and the phase-shifted first intermediate signal on a first coupled port of the coupler, an output signal on an output port of the coupler.