Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Matshushita Electric Industrial Co., Ltd.

Tomoyasu Fujishima

Hiroshi Kanno

Ushio Sangawa

Kazuyuki Sakiyama

Akio Matsushita

Wataru Miyashita

Takayuki Hirano

Yohei Asada

Shunsuke Ikeda

A signal processing device includes: a processor; and a memory having instructions. When executed by the processor, the instructions cause the signal processing device to perform operations including: converting a first signal that is a time domain signal into a second signal that is a frequency domain signal in response to reception of the first signal, the first signal containing noise superimposed on a broadcast electric signal derived from a broadcast electromagnetic wave, the noise having peaks of amplitude at regular frequency intervals in the frequency domain; calculating a frequency interval between the peaks of the noise in the frequency domain based on a correlation of the second signal; determining a frequency shift amount in the frequency domain based on the frequency interval; and shifting a frequency of the second signal by the frequency shift amount to create a frequency-shifted signal.

Signal processing device and signal processing method

A receiving device includes: a frequency mixer that converts a frequency of a reception signal to a baseband; an envelope demodulator; an upper sideband demodulator; and a lower sideband demodulator. Each of the envelope demodulator, the upper sideband demodulator and the lower sideband demodulator demodulates an output from the frequency mixer. The receiving device further includes: a first adder that adds an output from the envelope demodulator and an inverted output obtained by inverting an output from the upper sideband demodulator; a second adder that adds the output from the envelope demodulator and an inverted output obtained by inverting an output from the lower sideband demodulator; and a third adder that adds the output from the envelope demodulator, an inverted output obtained by inverting an output from the first adder, and an inverted output obtained by inverting an output from the second adder, to output a demodulation signal.

Receiving device, receiving method, and receiving system

A C/N ratio detection circuit includes a voltage detector, an averaging section, a time variation range calculator, and a C/N ratio calculator. The voltage detector measures an input voltage of a signal. The averaging section calculates an average of the input voltage over a predetermined time. The time variation range calculator calculates a time variation range of the input voltage over the predetermined time. The C/N ratio calculator calculates a C/N ratio of the signal by using the average and time variation range of the input voltage.

C/N ratio detection circuit and signal receiving circuit

A photonic crystal device according to the present invention includes: a first dielectric substratehaving a first lattice structure, of which the dielectric constant changes periodically within a first plane; a second dielectric substratehaving a second lattice structure, of which the dielectric constant changes periodically within a second plane; and an adjustment device (pivot) for changing a photonic band structure, defined by the first and second lattice structures, by varying relative arrangement of the first and second lattice structures. The first and second dielectric substratesandare stacked one upon the other.

Photonic crystal device

A slot antenna apparatus includes a grounding conductor having an outer edge including a first portion and a second portion, a one-end-opened slot formed in the grounding conductor along a radiation direction such that an open end is provided at a center of the first portion, a first feed line intersecting with the slot to feed radio-frequency signals, a second feed line connected to an external circuit, and a signal processing circuit including active elements and connected between the first and second feed lines and connected to the grounding conductor. The grounding conductor is configured to be symmetric about an axis parallel to the radiation direction and passing through the slot, and is provided with a grounding terminal on the axis of symmetry at the second portion. The grounding terminal is to be connected to a ground of the external circuit.

Slot antenna apparatus eliminating unstable radiation due to grounding structure

A slot antenna apparatus includes a grounding conductor having an outer edge including a first portion facing a radiation direction and a second portion other than the first portion, a one-end-open feed slot formed in the grounding conductor along the radiation direction such that an open end is provided at a center of the first portion, and a feed line including a strip conductor close to the grounding conductor and intersecting with the feed slot at at least a part thereof to feed a radio frequency signal to the feed slot. The slot antenna apparatus further comprises at least one one-end-open parasitic slot having an electrical length equivalent to one-quarter effective wavelength in a certain stop band, the parasitic slot having an open end at the second portion, and being formed in the grounding conductor so as not to intersect with the feed line.

Wide-band slot antenna apparatus with stop band

A slot antenna apparatus including: a grounding conductor having an outer edge including a first portion facing a radiation direction and a second portion other than the first portion, a one-end-open slot formed in the grounding conductor along the radiation direction such that an open end is provided at a center of the first portion, and a feed line including a strip conductor close to the grounding conductor and intersecting with the slot at least a part thereof to feed a radio frequency signal to the slot. The grounding conductor is formed to include at least one section at the second portion, the at least one section gradually approaches an axis passing through the slot and parallel to the radiation direction with increasing distance from the first portion.

Wide-band slot antenna apparatus with constant beam width

A polarization switching/variable directivity antenna according to the present invention includes a ground conductor plateon a surface of a dielectric substrate, and has a radiation element, a directivity switching element, and polarization switching elementsprovided on the ground conductor plateside of the dielectric substrate. The radiation elementincludes a first slotformed by removing a loop-like portion from the ground conductor plate. The directivity switching elementincludes a second slotformed by removing a loop-like portion from the ground conductor plateand directivity switching switches. The polarization switching elementsincludes a third slotformed by removing a linear-shaped portion from the ground conductor plateand polarization switching switchesto. Through control of the directivity switching switches, switching of a maximum gain direction of radiation directivity of the antenna is realized. Through control of the polarization switching switchesto, switching of a rotation direction of a circularly polarized wave which is emitted from the antenna can be realized.

Polarization switching/variable directivity antenna

A variable slot antenna includes: ground conductorsand, which are divided by a slot regionboth of whose both ends are open endsand; a feed linefor feeding power to the slot region; a first selective conduction pathconnecting between the ground conductorsandin a direction of the open endas viewed from a feeding site; and a second selective conduction pathconnecting between the ground conductorsandin a direction of the open endas viewed from the feeding site. In a first driving state, the first selective conduction pathis allowed to conduct and the second selective conduction pathis left open, so that a main beam is emitted in a directionof the second selective conduction pathas viewed from the feeding site. In another driving state, the selective conduction paths are controlled differently so that the main beam direction is switched to a direction

Variable slot antenna and driving method thereof

A transmission line pair has two transmission lines placed adjacent to each other in parallel to a signal transmission direction of the transmission lines as a whole. Each of the transmission lines includes a first signal conductor which is placed on one surface of a substrate formed from a dielectric or semiconductor and which is formed so as to be curved toward a first rotational direction within the surface, and a second signal conductor which is formed so as to be curved toward a second rotational direction opposite to the first rotational direction and which is placed in the surface so as to be electrically connected in series to the first signal conductor. A transmission-direction reversal portion in which a signal is transmitted along a direction reversed with respect to the signal transmission direction of the transmission lines as a whole is formed so as to include at least part of the first signal conductor and part of the second signal conductor. Thus, the transmission line pair is enabled to maintain successful isolation characteristics.

Transmission line pair having a plurality of rotational-direction reversal structures

A differential transmission line includes: a substrate; a ground conductor layer; and a first and a second signal conductor disposed in parallel to each other on the substrate. The first signal conductor and the ground conductor layer compose a first transmission line, whereas the second signal conductor and the ground conductor layer compose a second transmission line. The first transmission line and the second transmission line compose a differential transmission line. The differential transmission line includes two straight regions and a curved region, interconnecting the two straight regions.

Differential transmission line having curved section with reduced line width

A variable-directivity antenna according to the present invention includes at least three linear passive elements, which are arranged parallel to a Z-axis so as to surround a feed element. Each of those passive elements includes at least two element pieces, etc. that are arranged parallel to the Z-axis and switching elements, etc. of a first type. The passive element assembly further includes at least one switching element, etc. of a second type that makes two adjacent passive elements electrically continuous with each other when turned ON but electrically insulates them from each other when turned OFF. By turning ON and OFF the at least one switching element of the first type and the at least one switching element of the second type, the antenna can change its directivities. As a result, a linear variable-directivity antenna, which can change its radiation directivities within a vertical plane and of which the overall length in the longitudinal (or major-axis) direction does not increase excessively due to the presence of the passive elements, is realized.

Variable-directivity antenna

A differential transmission line includes: a substrate; a ground conductor layer; and a first and a second signal conductor disposed in parallel to each other on the substrate. The first signal conductor and the ground conductor layer compose a first transmission line, whereas the second signal conductor and the ground conductor layer compose a second transmission line. The first transmission line and the second transmission line compose a differential transmission line. The differential transmission line includes a curved region, with a straight region being connected to each end of the curved region. In the ground conductor layer in the curved region, a plurality of slots orthogonal to a local transmission direction of signals in the curved region are formed, and the slots are connected to one another on the inner side of the curvature.

Differential transmission line having a curved region with selected radius of curvature

In a transmission line pair including a first transmission line and a second transmission line which is so placed in adjacency that a coupled line region to be coupled with the first transmission line is formed, in the coupled line region, the first transmission line includes a first signal conductor which is placed on one surface which is either a top face of a substrate formed from a dielectric or semiconductor or an inner-layer surface parallel to the top face and which has a linear shape along its transmission direction, and the second transmission line includes a second signal conductor which is placed on the one surface of the substrate and which partly includes a transmission-direction reversal region for transmitting a signal along a direction having an angle of more than 90 degrees with respect to the transmission direction within the plane of the placement, and which has a line length different from that of the first signal conductor.

Growing community of inventors

Osaka, Japan

Tomoyasu Fujishima