Radar sensor

A method for determining relative displacement L between an object and a radar sensor using a first and a second continuous wave (CW) radar transceiver provided within the radar sensor, whereby the method comprises:

• generating, by a voltage-controlled oscillator (VCO) provided within each CW radar transceiver, an output signal having a specific frequency;
• dividing, by a divider circuit provided within each CW radar transceiver, the output signal from the VCO into a reference signal and a transmission signal;
• receiving, by a double periodic composite right/left hand (CRLH) substrate integrated waveguide (SIW) leaky wave antenna provided within each CW radar transceiver, the transmission signal from the divider circuit and transmitting a backward or forward main beam, wherein a direction of the transmitted main beam is determined by the specific frequency of the received transmission signal, and when the main beam is reflected back to the antenna by an object adjacent the sensor, generating, by the CRLH SIW leaky wave antenna, a backscattered signal based on the reflected main beam;
• dividing, by the divider circuit, the backscattered signal received from the antenna;
• receiving, by input ports of a six-port interferometer provided within each CW radar transceiver, the reference signal and the divided-backscattered signal from the divider circuit, whereby the six-port interferometer generates power signals at output ports of the six-port interferometer based on the received reference and divided-backscattered signals, the power signals being used for computing relative displacement L between the object and the radar sensor,
• whereby the double periodic CRLH SIW leaky wave antenna of the first CW radar transceiver is positioned adjacent the double periodic CRLH SIW leaky wave antenna of the second CW radar transceiver and,
• whereby the VCOs of the first and second CW radar transceivers are each tuned to generate output signals that each have a different specific frequency such that the main beam of the double periodic CRLH SIW leaky wave antenna of the first CW radar transceiver and the main beam of the double periodic CRLH SIW leaky wave antenna of the second CW radar transceiver are pointing at a same direction.