Abstract: An antenna device for a vehicle includes an antenna element having a first main surface, a shielding plate having a second main surface facing the first main surface and wider than the first main surface, the shielding plate being located between the antenna element and a noise source in the vehicle, and an insulating member located between the first main surface and the second main surface to integrate the antenna element and the shielding plate.

Abstract: A vehicle antenna device is configured to provide effective noise shielding, and to have a reduced thickness. The vehicle antenna device includes a first element and a second element. The first element functions as a capacitive antenna and supports a first frequency band. The second element functions as a resonant antenna and is disposed at a position capable of shielding noise from a noise source to the first element and shields the noise. The second element supports a second frequency band higher than the first frequency band. An attenuator circuit attenuating a signal of the first frequency band may be connected to the second element.

Abstract: A noise reduction device includes: a combiner to shift a phase of one of a first signal propagating through a first propagation path and a second signal propagating through a second propagation path by a predetermined angle and combine the phase-shifted one signal of the first signal and the second signal with the other signal of the first signal and the second signal; and a phase difference absorption circuit having a phase shift characteristic that reduces a difference between a phase difference between two signals each having a lower limit frequency of a band of the broadcast wave and passing through the first propagation path and the second propagation path and a phase difference between two signals each having an upper limit frequency of the band of the broadcast wave and passing through the first propagation path and the second propagation path.

Abstract: A power feed circuit for a circularly polarized antenna includes a synthesizing-distributing unit and a phase shift unit. The synthesizing-distributing unit distributes input signals to two paths with the same phase and same amplitude. The phase shift unit has two phase shift circuits connected respectively between the two paths distributed by the synthesizing-distributing unit and two feed points of a circularly polarized antenna. The phase shift unit outputs signals whose phase difference is 90° to the two feed points and of the circularly polarized antenna.

Abstract: A noise reduction device includes: a combiner to shift a phase of one of a first signal propagating through a first propagation path and a second signal propagating through a second propagation path by a predetermined angle and combine the phase-shifted one signal of the first signal and the second signal with the other signal of the first signal and the second signal; and a phase difference absorption circuit having a phase shift characteristic that reduces a difference between a phase difference between two signals each having a lower limit frequency of a band of the broadcast wave and passing through the first propagation path and the second propagation path and a phase difference between two signals each having an upper limit frequency of the band of the broadcast wave and passing through the first propagation path and the second propagation path.

Abstract: An antenna device for a vehicle includes an antenna element having a first main surface, a shielding plate having a second main surface facing the first main surface and wider than the first main surface, the shielding plate being located between the antenna element and a noise source in the vehicle, and an insulating member located between the first main surface and the second main surface to integrate the antenna element and the shielding plate.

Abstract: A vehicle-body-embedded antenna device includes an antenna element, a circuit board, a coil and a ground bracket. The antenna element of a grounded type has an antenna capacitance adapted to function as a capacitive antenna that supports a first frequency band, and main polarization thereof is polarization substantially parallel to the roof surface. The coil is placed on the circuit board and connected to the power feeding part to which the antenna element is connected for making the antenna element to have an antenna length supporting a second frequency band. The ground bracket is directly grounded to a conductive member of the vehicle body which is provided at an angle different from an angle of the roof surface for improving polarization sensitivity of the antenna element substantially perpendicular to the roof surface.

Abstract: A vehicle-body-embedded antenna device includes an antenna element, a circuit board, a coil and a ground bracket. The antenna element of a grounded type has an antenna capacitance adapted to function as a capacitive antenna that supports a first frequency band, and main polarization thereof is polarization substantially parallel to the roof surface. The coil is placed on the circuit board and connected to the power feeding part to which the antenna element is connected for making the antenna element to have an antenna length supporting a second frequency band. The ground bracket is directly grounded to a conductive member of the vehicle body which is provided at an angle different from an angle of the roof surface for improving polarization sensitivity of the antenna element substantially perpendicular to the roof surface.

Abstract: A low-profile antenna device is provided for a vehicle. The low-profile antenna device includes a base plate, a circuit board, a base, a top-load element and a coil. The circuit board is disposed on the base plate, in parallel with the base plate. An amplifier circuit is placed on a front surface side of the circuit board, and a ground plate area having a ground plate and an empty area not having a ground plate are provided on a back, surface of the circuit board. The coil is disposed on the front surface side of the circuit board facing the empty area of the circuit board. The coil is disposed in a manner axially parallel with the circuit board, connected between the top-load element and the amplifier circuit, and adjusted to function as a resonance antenna.

Abstract: A low-profile antenna device is provided for a vehicle. The low-profile antenna device includes a base plate, a circuit board, a base, a top-load element and a coil. The circuit board is disposed on the base plate, in parallel with the base plate. An amplifier circuit is placed on a front surface side of the circuit board, and a ground plate area having a ground plate and an empty area not having a ground plate are provided on a back, surface of the circuit board. The coil is disposed on the front surface side of the circuit board facing the empty area of the circuit board. The coil is disposed in a manner axially parallel with the circuit board, connected between the top-load element and the amplifier circuit, and adjusted to function as a resonance antenna.

Abstract: Provided is a low-profile antenna device that allows the height of an antenna to be further reduced. The low-profile antenna device comprises a base section, a helical antenna section, and a top load section. The helical antenna section is wound along an oblique axial direction starting from the base section. The conductive top load section, which is electrically connected to the tip of the helical antenna section, has a top section that is provided on the opposite side to a vehicle, to which the antenna device is fixed, and side sections that are provided on the vehicle side in oblique directions from the top section such that no part of the helical antenna section is placed between the top load section and the vehicle in the direction of a perpendicular line formed therebetween.

Abstract: Provided is a low-profile antenna device that allows the height of an antenna to be further reduced. The low-profile antenna device comprises a base section, a helical antenna section, and a top load section. The helical antenna section is wound along an oblique axial direction starting from the base section. The conductive top load section, which is electrically connected to the tip of the helical antenna section, has a top section that is provided on the opposite side to a vehicle, to which the antenna device is fixed, and side sections that are provided on the vehicle side in oblique directions from the top section such that no part of the helical antenna section is placed between the top load section and the vehicle in the direction of a perpendicular line formed therebetween.

Abstract: An optical recording device that records to a multi-layer disk having multiple recording layers includes a controller which sets a data area in which user data is recorded, and a calibration area including a main calibration area and at least one sub-calibration area which are used to calibrate the intensity of laser light for recording, with the same layout among the plurality of recording layers, conducts first calibration for performing initial recording in the data area by using the main calibration area, records dummy data in the remainder of the main calibration area, and conducts second calibration for performing additional recording in the data area by using the sub-calibration area.

Abstract: An optical recording device that records to a multi-layer disk having multiple recording layers includes a controller which sets a data area in which user data is recorded, and a calibration area including a main calibration area and at least one sub-calibration area which are used to calibrate the intensity of laser light for recording, with the same layout among the plurality of recording layers, conducts first calibration for performing initial recording in the data area by using the main calibration area, records dummy data in the remainder of the main calibration area, and conducts second calibration for performing additional recording in the data area by using the sub-calibration area.

Abstract: An optical recording device for recording to a disk having a guide layer and a plurality of recording layers includes a controller which obtains, by calculation, logical addresses of data areas of all recording layers on the basis of physical addresses of a guide layer and recording layer information. Specifically, in treating the maximum value (last physical address) of physical addresses in the guide layer as PSN_max, recording layer information of recording layer Lx as x (x=0, 1, 2, . . . ), physical addresses corresponding to recording destination positions in the data area of recording layer Lx as PSN, and logical addresses imparted to data units recorded at recording destination positions in the data area of recording layer Lx as LSN, calculation for LSN=(PSN_max*x)+PSN . . . (1) is performed.

Abstract: A multi-layer recording medium is constituted by guide layer-equipped optical disks having a plurality of recording layers and guide layers are integrated by bonding said disks to one another so as to produce a double-sided disk, both sides of which may be used for recording. With regards to the lead-in areas for the guide layers of the guide layer-equipped optical disks for both sides, single-sided disks and double-sided disks are identified, and face-management information for identifying the side surfaces in the case of a double-sided disk is recorded in advance in said lead-in areas using wobbles or the like. As a result, the likelihood of the occurrence of defective products caused by the inability to read the face information can be reduced.

Abstract: An operation for recording a recording signal onto a disk (1) is interrupted, when an amount of signal data stored in a buffer RAM (11) for temporarily storing the recording signal is less than an interruption setting value during performing of the recording operation. Moreover, when the amount of signal data stored in the buffer RAM (11) increases and indicates a resumption setting value, the signal recorded on the disk (1) before interruption is reproduced, and the recording operation is resumed based on the reproduced signal. Moreover, recording properties are detected by the signal reproduced before resumption of recording.

Abstract: A disk divided into a trial writing region, buffer region, read-in region, program region, and read-out region disposed from an inner peripheral side toward an outer peripheral side is rotated at a constant angular speed. A test signal is recorded in the trial writing region and an outer peripheral region disposed outside the read-out region, the recorded test signals are read, and a laser output value is set based on the reproduced test signals of the two regions.

Abstract: An operation for recording a recording signal onto a disk (1) is interrupted, when an amount of signal data stored in a buffer RAM (11) for temporarily storing the recording signal is less than an interruption setting value during performing of the recording operation. Moreover, when the amount of signal data stored in the buffer RAM (11) increases and indicates a resumption setting value, the signal recorded on the disk (1) before interruption is reproduced, and the recording operation is resumed based on the reproduced signal. Moreover, recording properties are detected by the signal reproduced before resumption of recording.

Abstract: A disk divided into a trial writing region, buffer region, read-in region, program region, and read-out region disposed from an inner peripheral side toward an outer peripheral side is rotated at a constant angular speed. A test signal is recorded in the trial writing region and an outer peripheral region disposed outside the read-out region, the recorded test signals are read, and a laser output value is set based on the reproduced test signals of the two regions.