Electronic device
An electronic device includes a transmission unit that transmits a transmission wave from a transmission antenna; a reception unit that receives, from a reception antenna, a reflected wave of the transmission wave; a controller that detects an object that reflects the transmission wave; a power supply device that supplies electric power to at least any of the foregoing components; and a substrate having the foregoing components thereon. The transmission and reception antennas are disposed on a first surface of the substrate. The controller and the power supply device are disposed on a second surface of the substrate opposite to the first surface. The substrate includes a waveguide that guides the transmission wave and/or the reflected wave between the first and second surfaces and is covered with an electromagnetic wave shielding member apart from the second surface by a distance of ¼ of a wavelength of the transmission or reflected wave.
1 . An electronic device comprising:
a transmission antenna;
a transmission unit configured to transmit a transmission wave from the transmission antenna;
a reception antenna;
a reception unit configured to receive, from the reception antenna, a reflected wave that is the transmission wave having been reflected;
a controller configured to detect an object that reflects the transmission wave, based on a transmission signal transmitted as the transmission wave and a reception signal received as the reflected wave;
a power supply device configured to supply electric power to at least any of the transmission unit, the reception unit, or the controller; and
a substrate on which the transmission antenna, the reception antenna, the controller, and the power supply device are disposed,
wherein the transmission antenna and the reception antenna are disposed on a first surface of the substrate,
the transmission unit, the reception unit, the controller and the power supply device are disposed on a second surface of the substrate, the second surface being opposite to the first surface,
the substrate includes a waveguide configured to guide at least one of the transmission wave between the transmission antenna and the transmission unit or the reflected wave between the reception antenna and the reception unit, and
the waveguide is covered with an electromagnetic wave shielding member that is apart from the second surface of the substrate by a distance of ¼ of a wavelength of the transmission wave or the reflected wave.
2 . The electronic device according to claim 1 , wherein the power supply device is covered with an electromagnetic wave shielding member on the second surface side of the substrate.
3 . The electronic device according to claim 1 , wherein the power supply device includes a low dropout regulator.
4 . The electronic device according to claim 3 , wherein the power supply device is covered with an electromagnetic wave shielding member on the second surface side of the substrate, and a heat dissipation sheet is interposed between the power supply device and the electromagnetic wave shielding member.
5 . The electronic device according to claim 1 , wherein the power supply device includes a switching power supply.
6 . The electronic device according to claim 1 , wherein the electronic device is covered with a resin member that is apart from the first surface of the substrate by a distance of ½ of a wavelength of the transmission wave or the reflected wave.
7 . The electronic device according to claim 1 , wherein the transmission unit includes a signal generating unit, a synthesizer, a phase control unit, and an amplifier, and
the reception unit includes a low noise amplifier, a phase control unit, a mixer, a frequency conversion unit, and an analog-to-digital conversion circuit.