Multifunctional radar systems and methods of operation thereof

A method of operating a radar system, the method comprising:

• receiving, by a first receive antenna implemented in a first conductive layer at a first side of a substrate, a first reflected radio frequency (RF) signal, the substrate being a circuit board substrate or a wafer substrate;
• detecting, by RF circuitry, a first object located on the first side of the substrate according to the first reflected RF signal, the RF circuitry being operatively coupled to the first receive antenna;
• receiving, by a second receive antenna implemented in a second conductive layer at a second side of the substrate and operatively coupled to the RF circuitry, a second reflected RF signal;
• shielding the first receive antenna from the second receive antenna using a ground plane region implemented in a third conductive layer within the substrate between the first conductive layer and the second conductive layer;
• detecting, by the RF circuitry, biometric data from a second object located on the second side of the substrate according to the second reflected RF signal, wherein the second side is opposite of the first side;
• detecting, by the RF circuitry, motion of the first object;
• and
• interpreting the motion of the first object as a gesture for controlling the radar system.

A radar system comprising:

• a multilayer circuit board comprising a front side, a first conductive layer disposed within the multilayer circuit board at the front side, a back side opposite the front side, and a second conductive layer disposed within the multilayer circuit board at the back side;
• an integrated circuit (IC) chip physically and electrically coupled to the back side of the multilayer circuit board, the IC chip comprising a radar system circuit and a digital signal processor (DSP);
• a first receive antenna and a second receive antenna disposed at the front side and configured to receive a first reflected radio frequency (RF) signal, the first receive antenna and second receive antenna being operationally coupled to the radar system circuit and the DSP using transmission lines and interconnects implemented in the second conductive layer;
• a flexible substrate comprising a proximal end coupled to the multilayer circuit board;
• a third receive antenna disposed at a distal end of the flexible substrate and configured to receive a second reflected RF signal, the flexible substrate extending from the back side and bending so that the distal end including the third receive antenna is spatially separated from and vertically overlaps the back side;
• a ground plane region implemented in the first conductive layer and configured to shield the first receive antenna and the second receive antenna from the third receive antenna;
• and
• RF circuitry disposed in the radar system circuit and operatively coupled to the first receive antenna, the second receive antenna, the third receive antenna, and the DSP, the RF circuitry being configured to
• detect a first object located on the front side of the multilayer circuit board according to the first reflected RF signal, and
• detect biometric data from a second object located on the back side of the multilayer circuit board according to the second reflected RF signal.

A method of operating a radar system, the method comprising:

• receiving, by a first receive antenna implemented in a first conductive layer at a first side of a substrate, a first reflected radio frequency (RF) signal, the substrate being a circuit board substrate or a wafer substrate;
• detecting, by RF circuitry, a first object located on the first side of the substrate according to the first reflected RF signal, the RF circuitry being operatively coupled to the first receive antenna;
• receiving, by a second receive antenna implemented in a second conductive layer at a second side of the substrate and operatively coupled to the RF circuitry, a second reflected RF signal;
• shielding the first receive antenna from the second receive antenna using a ground plane region implemented in a third conductive layer within the substrate between the first conductive layer and the second conductive layer;
• detecting, by the RF circuitry, biometric data from a second object located on the second side of the substrate according to the second reflected RF signal, wherein the second side is opposite of the first side;
• and
• wherein the radar system is an earphone device, a headphone device, a headset device, or an earbud device.