Abstract: A method with which the reception sensitivity of a communication device can be measured accurately and with satisfactory reproducibility and a method with which the effect of noise control performed upon a communication device can be accurately evaluated. A first communication device in a nonreflective environment in an anechoic chamber wirelessly receives a test signal transmitted from a pseudo base station through an attached antenna thereof at the same time when a second communication device near the first communication device receives the test signal through a signal line. The first communication device is simultaneously subjected to the interference of noise generated by the second communication device at the attached antenna. Thus, the noise is made to interfere with the attached antenna of the first communication device without disassembling the first communication device and moving the first communication device in the nonreflective environment.

Abstract: A power supply circuit includes a switching element coupled in a current path between an input terminal and an output terminal and includes a smoothing capacitor coupled between the output terminal and a ground. A bypass capacitor is coupled between the input terminal and the ground. An antenna element shares the ground with the power supply circuit. A frequency filter having a stop band that is an operating frequency band of the antenna element is inserted in series in at least either a current path between the switching element and the smoothing capacitor or a current path between the bypass capacitor and the switching element. It is possible to suppress deterioration of wireless communication quality due to noise caused in a DC-DC converter.

Abstract: A power supply circuit board includes a substrate, a first line that is provided on a first main surface of the substrate and that has a land, a second line that is provided on the first main surface of the substrate and that has a land, an inductor that is connected to the land of the first line and the land of the second line and that is made of a ferrite material, and an open stub that is connected to at least one of the first line and the second line.

Abstract: A method with which the reception sensitivity of a communication device can be measured accurately and with satisfactory reproducibility and a method with which the effect of noise control performed upon a communication device can be accurately evaluated. A first communication device in a nonreflective environment in an anechoic chamber wirelessly receives a test signal transmitted from a pseudo base station through an attached antenna thereof at the same time when a second communication device near the first communication device receives the test signal through a signal line. The first communication device is simultaneously subjected to the interference of noise generated by the second communication device at the attached antenna. Thus, the noise is made to interfere with the attached antenna of the first communication device without disassembling the first communication device and moving the first communication device in the nonreflective environment.

Abstract: A receiver device includes an antenna that receives a high frequency signal having a bandwidth, a mixer connected to the antenna and a frequency multiplier. A filter that removes a noise signal whose frequency is different from that of the local signal is provided between the local oscillator and the frequency multiplier. The filter removes the noise signal that satisfies the condition that the absolute value of the frequency difference between the center frequency of the local signal and the center frequency of the noise signal is less than the bandwidth of the high frequency signal.

Abstract: A power supply circuit includes a switching element coupled in a current path between an input terminal and an output terminal and includes a smoothing capacitor coupled between the output terminal and a ground. A bypass capacitor is coupled between the input terminal and the ground. An antenna element shares the ground with the power supply circuit. A frequency filter having a stop band that is an operating frequency band of the antenna element is inserted in series in at least either a current path between the switching element and the smoothing capacitor or a current path between the bypass capacitor and the switching element. It is possible to suppress deterioration of wireless communication quality due to noise caused in a DC-DC converter.

Abstract: A power supply circuit board includes a substrate, a first line that is provided on a first main surface of the substrate and that has a land, a second line that is provided on the first main surface of the substrate and that has a land, an inductor that is connected to the land of the first line and the land of the second line and that is made of a ferrite material, and an open stub that is connected to at least one of the first line and the second line.

Abstract: A receiver device includes an antenna that receives a high frequency signal having a bandwidth, a mixer connected to the antenna and a frequency multiplier. A filter that removes a noise signal whose frequency is different from that of the local signal is provided between the local oscillator and the frequency multiplier. The filter removes the noise signal that satisfies the condition that the absolute value of the frequency difference between the center frequency of the local signal and the center frequency of the noise signal is less than the bandwidth of the high frequency signal.

Abstract: An S-parameter of an object to be measured is measured, which includes (i) three transmission lines configured such that a ternary signal is transmitted through a corresponding one of the three transmission lines and (ii) six ports as total ports included in the three transmission lines each having a pair of ports. Based on the measured S-parameter, a parameter is calculated, which shows transparent characteristics in each mode among mixed-mode S-parameters in accordance with transition patterns of signal levels on the three transmission lines.

Abstract: An electronic apparatus includes a radio communication unit employing a WiGig method and a radio communication unit employing a Wi-Fi method. A bias T circuit is included in the radio communication unit employing the WiGig method. The bias T circuit includes inductors and a filter. The inductors are disposed between a signal line and a DC-DC converter, and are connected in series to each other. The filter has attenuation characteristics in a frequency band used by the radio communication unit employing the Wi-Fi method. One end of the filter is connected between the signal line and one of the inductors located at a first stage from the signal line.

Abstract: Three or more of n inductors are arranged inside an insulating member. Inside the insulating member, each of the inductors includes coil conductors that are contained in respective coil conductor layers that are stacked in a first direction and via conductors, each of which connects the coil conductors that are contained in the coil conductor layers adjoining in the first direction. Each of the coil conductor layers contains the n coil conductors of the inductors, and a pattern formed of the coil conductors contained in each of the coil conductor layers has n-fold rotational symmetry.

Abstract: A power supply circuit includes a plurality of power amplifiers for amplifying radio frequency signals, an envelope tracker for supplying a variable voltage based on an envelope signal to the power amplifiers, a common line connected to an output side of the envelope tracker, and a plurality of branch lines branching from a tip of the common line and connected to the power amplifiers, respectively. On the branch lines, sub-inductors are provided, respectively. On the common line, a main inductor and a capacitor are provided.

Abstract: A ground conductor film is formed at an insulating substrate. A floating conductor film capacitively couples to the ground conductor film. A radiating element is connected to the floating conductor film. A shielding film shields an electromagnetic wave radiated from the radiating element. By applying such a configuration to a printed circuit board, noise reduction can be achieved.

Abstract: A circuit board with a measure against high frequency noise includes: an interconnect substrate having an interconnect pattern to which an IC which is a source of high frequency noise is electrically connected; a pair of lands provided on a mounting surface of the interconnect substrate; and a chip component having a body composed of a magnetic body (i.e., ferrite) in a rectangular parallelepiped, and a pair of external electrodes provided at opposite ends of the body, the pair of external electrodes being connected to the pair of lands, the body being disposed on the interconnect pattern, as observed in a direction perpendicular to the mounting surface.

Abstract: A noise reducing electronic component is used as mounted on a circuit board. The noise reducing electronic component includes: a floating electrode disposed so as to be capacitively coupled to a ground conductor of the circuit board; a radiation element connected to the floating electrode; and a shielding member to shield electromagnetic waves radiated from the radiation element. With this noise reducing electronic component, noise in a printed circuit board and the like can be reduced.

Abstract: A power supply circuit includes a plurality of power amplifiers for amplifying radio frequency signals, an envelope tracker for supplying a variable voltage based on an envelope signal to the power amplifiers, a common line connected to an output side of the envelope tracker, and a plurality of branch lines branching from a tip of the common line and connected to the power amplifiers, respectively. On the branch lines, sub-inductors are provided, respectively. On the common line, a main inductor and a capacitor are provided.

Abstract: An electronic apparatus includes a radio communication unit employing a WiGig method and a radio communication unit employing a Wi-Fi method. A bias T circuit is included in the radio communication unit employing the WiGig method. The bias T circuit includes inductors and a filter. The inductors are disposed between a signal line and a DC-DC converter, and are connected in series to each other. The filter has attenuation characteristics in a frequency band used by the radio communication unit employing the Wi-Fi method. One end of the filter is connected between the signal line and one of the inductors located at a first stage from the signal line.

Abstract: Three or more of n inductors are arranged inside an insulating member. Inside the insulating member, each of the inductors includes coil conductors that are contained in respective coil conductor layers that are stacked in a first direction and via conductors, each of which connects the coil conductors that are contained in the coil conductor layers adjoining in the first direction. Each of the coil conductor layers contains the n coil conductors of the inductors, and a pattern formed of the coil conductors contained in each of the coil conductor layers has n-fold rotational symmetry.

Abstract: An S-parameter of an object to be measured is measured, which includes (i) three transmission lines configured such that a ternary signal is transmitted through a corresponding one of the three transmission lines and (ii) six ports as total ports included in the three transmission lines each having a pair of ports. Based on the measured S-parameter, a parameter is calculated, which shows transparent characteristics in each mode among mixed-mode S-parameters in accordance with transition patterns of signal levels on the three transmission lines.

Abstract: A circuit board with a measure against high frequency noise includes: an interconnect substrate having an interconnect pattern to which an IC which is a source of high frequency noise is electrically connected; a pair of lands provided on a mounting surface of the interconnect substrate; and a chip component having a body composed of a magnetic body (i.e., ferrite) in a rectangular parallelepiped, and a pair of external electrodes provided at opposite ends of the body, the pair of external electrodes being connected to the pair of lands, the body being disposed on the interconnect pattern, as observed in a direction perpendicular to the mounting surface.