Abstract: A wireless sensor apparatus includes first and second polarization antennas whose polarization surfaces of radiation waves are mutually orthogonal, a first mixer circuit connected to the first polarization antenna and configured to input a first reception signal received by the first polarization antenna, a second mixer circuit connected to the second polarization antenna and configured to input a second reception signal received by the second polarization antenna, a signal generation circuit configured to generate pulse signals fed to the first and second polarization antennas and also supplied to the first and second mixer circuits, and a differential amplification circuit configured to perform a differential amplification on a mixed output obtained by mixing the first reception signal and the pulse signal by the first mixer circuit and a mixed output obtained by mixing the second reception signal and the pulse signal by the second mixer circuit.

Abstract: A wireless sensor device includes a transmission signal generation unit that generates a frequency-spread high frequency transmission signal such that a transmission frequency is continuously increased and decreased with a predetermined period, a transmitter antenna that radiates the high frequency transmission signal, a receiver antenna that receives a reflected wave from an object having received the high frequency transmission signal, and outputs a frequency-spread high frequency reception signal, a mixer circuit that receives a part of the high frequency transmission signal as a first frequency-spread high frequency signal, receives the high frequency reception signal as a second frequency-spread high frequency signal, and outputs a DC beat signal by operating as a phase detector when frequencies of the first and second signals coincide with each other, and a DC component extraction circuit that extracts the DC beat signal from an output signal of the mixer circuit.

Abstract: A wireless sensor apparatus controls, in a case where wireless waves are radiated by feeding pulse signals generated by a signal generation circuit to antennas, an operation timing of the signal generation circuit and a path from the signal generation circuit to the antennas in such a manner that after a prior pulse signal is fed to the antenna and simultaneously supplied to a mixer circuit, at a proximate timing which does not overlap with a pulse width of the prior pulse signal supplied to the antenna and the mixer circuit, a next pulse signal is fed to the antenna and simultaneously supplied to a mixer circuit.

Abstract: A wireless sensor apparatus controls, in a case where wireless waves are radiated by feeding pulse signals generated by a signal generation circuit to antennas, an operation timing of the signal generation circuit and a path from the signal generation circuit to the antennas in such a manner that after a prior pulse signal is fed to the antenna and simultaneously supplied to a mixer circuit, at a proximate timing which does not overlap with a pulse width of the prior pulse signal supplied to the antenna and the mixer circuit, a next pulse signal is fed to the antenna and simultaneously supplied to a mixer circuit.

Abstract: A wireless sensor apparatus includes first and second polarization antennas whose polarization surfaces of radiation waves are mutually orthogonal, a first mixer circuit connected to the first polarization antenna and configured to input a first reception signal received by the first polarization antenna, a second mixer circuit connected to the second polarization antenna and configured to input a second reception signal received by the second polarization antenna, a signal generation circuit configured to generate pulse signals fed to the first and second polarization antennas and also supplied to the first and second mixer circuits, and a differential amplification circuit configured to perform a differential amplification on a mixed output obtained by mixing the first reception signal and the pulse signal by the first mixer circuit and a mixed output obtained by mixing the second reception signal and the pulse signal by the second mixer circuit.

Abstract: A wireless sensor device includes a transmission signal generation unit that generates a frequency-spread high frequency transmission signal such that a transmission frequency is continuously increased and decreased with a predetermined period, a transmitter antenna that radiates the high frequency transmission signal, a receiver antenna that receives a reflected wave from an object having received the high frequency transmission signal, and outputs a frequency-spread high frequency reception signal, a mixer circuit that receives a part of the high frequency transmission signal as a first frequency-spread high frequency signal, receives the high frequency reception signal as a second frequency-spread high frequency signal, and outputs a DC beat signal by operating as a phase detector when frequencies of the first and second signals coincide with each other, and a DC component extraction circuit that extracts the DC beat signal from an output signal of the mixer circuit.

Abstract: A diversity receiving device includes a plurality of mixers which are provided to correspond to antennas arranged so as to be separated from each other and each of which multiplies a radio frequency signal output from the corresponding antenna by a local oscillation signal to modulate the radio frequency signal into an intermediate frequency signal; a reference signal source that generates a reference signal; a plurality of local oscillating units which are provided to correspond to the plurality of mixers, and each of which generates a local oscillation signal having a frequency corresponding to the phase of the reference signal and supplies the local oscillation signal to the corresponding mixer; a filter circuit that is provided between the reference signal source and the plurality of local oscillating units and changes the phase of the reference signal supplied to all the local oscillating units or the local oscillating units other than one local oscillating unit according to a predetermined passband freq

Abstract: A smart antenna device includes: first and second weighting units provided to correspond to two antennas disposed apart from each other so as to weight received signals inputted from the antennas, respectively; an operating unit that obtains a ratio of a weight of the second weighting unit to a weight of the first weighting unit; an adding unit that adds a signal outputted from the first weighting unit and a signal outputted from the second weighting unit to each other; and a phase shifting unit that makes phases of the two signals equal to each other.

Abstract: An antenna device includes a circuit board, an upper shield case, a lower shield case, and a power feeding member. The circuit board has high frequency circuits arranged thereon. The upper shield case and the lower shield case cover the circuit board. The power feeding member extends from an upper plate of the upper shield case. Radiation slots and are formed in the upper plate. The power feeding member includes a horizontal portion, a bent portion, and a drooping portion, and a front end of the drooping portion is mounted on a land of the circuit board and soldered thereto. The horizontal portion protrudes from a base end which is continuous to the upper plate in a horizontal direction. The bent portion is formed by bending a front end of the horizontal portion at a right angle. The drooping portion extends downward from the bent portion.

Abstract: A comparator for comparing an AFC output an analog demodulation circuit with a predetermined reference voltage Vref, an OR gate to which two inputs including an output of the comparator and a channel select signal are input, and a switch for connecting a crystal oscillator of a digital demodulation circuit to the digital demodulation circuit when an output of the OR gate is “H (or 1)” are provided. When an analog broadcast signal that should be received is not normally received, the crystal oscillator of the digital demodulation circuit is connected to the digital demodulation circuit to operate the digital demodulation circuit. Then, the channel select signal is supplied to a PLL circuit of a tuner front end via the digital demodulation circuit.

Abstract: In an antenna system, a short-circuiting conductive plate and a power-supply conductive plate are bent at the center region of a metal plate so as to be perpendicular to the planar surface of the metal plate. The remaining metal plate excluding the short-circuiting conductive plate and the power-supply conductive plate constitutes the emission conductive plate. The antenna system is mounted on a ground plane and the emission conductive plate is disposed parallel to the ground plane. The bottom end of the short-circuiting conductive plate is soldered to the ground plane and the bottom end of the power-supply conductive plate is connected to a power-supply circuit.

Abstract: A pair of radiating slots open in a flat metal plate having a square shape to be line-symmetrically arranged with respect to a symmetry axis, and power feeding lines and ground lines are provided at power feeding positions of the respective radiating slots. The respective radiating slots have first slot portions and second slot portions that contact at 45 degrees and linearly extend, respectively. Both the radiating slots are arranged in a back-to-back manner that edges of the first slot portions face each other, and the second slot portions extend in a direction to be separated from each other along two sides of the flat metal plate. Further, a polarization direction of an electric wave to be generated by one radiating slot and a polarization direction of an electric wave to be generated by the other radiating slot are set to be perpendicular to each other.

Abstract: An antenna device includes a plate-shaped conductor and a radiating conductor that extends outward from an end portion of the conductor and has a length corresponding to a quarter wavelength of a first frequency. A strip-shaped slot portion formed by removing a part of the plate-shaped conductor extending inward from the end portion has a length corresponding to a quarter wavelength of a second frequency. A feed portion is perpendicular to the slot portion and crosses over the slot portion. The feed portion feeds the same signals to the slot portion and the radiating conductor.

Abstract: In an antenna device, a radiation slot formed in a metal plate includes a main slot part on one diagonal line of the metal plate and first and second branch slot parts. The first and second branch split parts extend along two adjacent sides of the metal plate and are connected to one end of the main slot part. A power feeder line and a ground line are formed in the vicinity of another end of the main slot part. The length and relative position of each slot part is set such that the plane of polarization of an electric wave radiated from the main and first slot parts and the plane of polarization of an electric wave radiated from the main and second slot parts are orthogonal to each other and the two electric waves differ in phase by 90 degrees.

Abstract: The antenna device 1 contains a first radiating conductive plate 3 arranged above a grounding conductor 2 so as to be substantially parallel and opposite to the grounding conductor 2; a second radiating conductive plate 4 adjacent to the first radiating conductive plate 3 with a slit 5 interposed therebetween; a feeding conductive plate 6 that extends orthogonally from an outer edge of the first radiating conductive plate 3 adjacent to the slit 5, and a shorting conductive plate 7 that extends orthogonally from an outer edge of the second radiating conductive plate 4 adjacent to the slit 5. A lower end of the feeding conductive plate 6 is connected to a feeding circuit, and a lower end of the shorting conductive plate 7 is connected to the grounding conductor 2.

Abstract: The present invention provides a slot antenna in which the radiation toward the zenith direction is not obstructed although it is arranged on an upper side of a ground conducting plate. The antenna device 11 operates as the slot antenna by providing a slot 14 in an upper plate portion 13 of a shield case 12. The shield case 12 is provided on a ground conducting plate 20. The slot 14 is composed of a first aperture 15 extending in a straight line, a second aperture 16 communicating with one end of the longitudinal direction of the first aperture 15, and a third aperture 17 communicating with the other end of the longitudinal direction of the aperture 15. The apertures 16 and 17 have the same triangular shapes which are point-symmetrical to the center of the aperture 15.

Abstract: An antenna includes a dielectric substrate disposed on a ground conductor and first and second radiating conductors containing meandering lines that are symmetrically disposed on a surface of the dielectric substrate and whose lower ends are connected at a junction. A third radiating conductor is disposed between the first radiating conductor and the second radiating conductor and extends in a straight line along the symmetry axis of both the radiating conductors. A capacitive conductor is disposed on the dielectric substrate and is substantially parallel to the ground conductor. The upper ends of the first, second and third radiating conductors are connected to the capacitive conductor. Power of a frequency supplied to the junction causes the first and second radiating conductors to resonate while power of a higher frequency causes the third radiating conductor to resonate.

Abstract: A slot antenna apparatus 10 contains a circuit substrate having a high-frequency circuit arranged therein and a shield case accommodating the circuit substrate. A cross-shaped slot and a feeding pin are formed in an upper plate of the shield case. The cross-shaped slot is composed of first and second slots. The lengths of the slots are different and the slots are perpendicular to each other. The shortest distances from the feeding pin to the first slots are approximately equal. When the power is fed to the upper plate through the feeding pin, the slots are excited to irradiate linearly polarized waves perpendicular to each other, respectively.

Abstract: In an antenna device, a radiation slot formed in a metal plate includes a main slot part on one diagonal line of the metal plate and first and second branch slot parts. The first and second branch split parts extend along two adjacent sides of the metal plate and are connected to one end of the main slot part. A power feeder line and a ground line are formed in the vicinity of another end of the main slot part. The length and relative position of each slot part is set such that the plane of polarization of an electric wave radiated from the main and first slot parts and the plane of polarization of an electric wave radiated from the main and second slot parts are orthogonal to each other and the two electric waves differ in phase by 90 degrees.

Abstract: A patch antenna apparatus includes an antenna element and a metal frame, which are disposed on a ground plane. The antenna element has a dielectric substrate, which has a patch electrode on the top surface and has a ground electrode on the bottom surface. The patch electrode is connected to current-feed pins. The metal frame is positioned so as to surround the peripheral surface of the dielectric substrate. The height dimension of the metal frame is set to be slightly larger than the thickness dimension of the dielectric substrate. Electromagnetic radiation radiated from the antenna element is reflected upon reaching the metal frame. Thus, the metal frame causes interference with the electromagnetic radiation such that the traveling direction of the electromagnetic radiation is redirected closer to the lateral direction.