Abstract: A coherent optical reception device includes a local oscillation laser that supplies laser light, a coherent optical reception front-end unit that receives a multi-level modulated optical signal, demodulates the optical signal on the basis of the laser light, and converts a demodulated optical signal into an electrical analog signal, an analog-to-digital converter that converts the analog signal into a digital signal, a compensation unit that compensates for an influence of dispersion due to a wavelength or a polarized wave of the optical signal and recovers a carrier phase of the digital signal, a constellation distortion compensation unit that compensates for constellation distortion of the multi-level modulation included in the digital signal in which an influence of dispersion is compensated for by the compensation unit, and an error correction decoding unit that performs error correction of the digital signal in which the constellation distortion is compensated for.

Abstract: A power combiner/power divider has a disk shaped housing cavity and a housing of electrically conductive material, such as metal. A junction pin is positioned centrally in the power combiner/divider. Additional ports are positioned radially along the periphery of the disk shaped portion. Tapered waveguides may extend from the radially positioned ports to the centrally positioned junction pin. A hollow radial cavity provided in the cavity holds a dielectric insert that may have tapering extensions radiating from a central ring. The ring surrounds the centrally positioned port.

Abstract: Fourier transform is performed on a reception signal to obtain a first calculation value. Fourier transform is performed on a known signal to obtain a second calculation value. The first calculation value is divided by the second calculation value to obtain a third calculation value. Inverse Fourier transform is performed on the third calculation value to obtain a fourth calculation value. A maximum value of an amplitude of the fourth calculation value and a sample point at which the maximum value is obtained are detected. The position of the known signal in the reception signal is detected from the sample point at which the maximum value is obtained.

Abstract: A terminal device including a detection unit that detects a sound, and an output unit that outputs information regarding a detection method of detecting the sound by the detection unit.

Abstract: A coherent optical reception device includes a local oscillation laser that supplies laser light, a coherent optical reception front-end unit that receives a multi-level modulated optical signal, demodulates the optical signal on the basis of the laser light, and converts a demodulated optical signal into an electrical analog signal, an analog-to-digital converter that converts the analog signal into a digital signal, a compensation unit that compensates for an influence of dispersion due to a wavelength or a polarized wave of the optical signal and recovers a carrier phase of the digital signal, a constellation distortion compensation unit that compensates for constellation distortion of the multi-level modulation included in the digital signal in which an influence of dispersion is compensated for by the compensation unit, and an error correction decoding unit that performs error correction of the digital signal in which the constellation distortion is compensated for.

Abstract: An optical signal transmission apparatus includes a modulation unit which modulates a transmission signal, a training signal sequence generation unit which generates a plurality of signal sequences having power concentrated in a plurality of different frequency bands, at least one of an amplitude and a phase of the plurality of signal sequences being modulated, as a training signal sequence, a signal multiplexing unit which appends the training signal sequence to the transmission signal, and an electro-optical conversion unit which converts a signal sequence obtained by appending the training signal sequence to the transmission signal into an optical signal and transmits the optical signal.

Abstract: A power combiner/power divider has a disk shaped housing cavity and a housing of electrically conductive material, such as metal. A junction pin is positioned centrally in the power combiner/divider. Additional ports are positioned radially along the periphery of the disk shaped portion. Tapered waveguides may extend from the radially positioned ports to the centrally positioned junction pin. A hollow radial cavity provided in the cavity holds a dielectric insert that may have tapering extensions radiating from a central ring. The ring surrounds the centrally positioned port.

Abstract: An increase in circuit scale is suppressed and a phase variation caused in a transmission path or the like is compensated for.

Abstract: A terminal device includes a detection unit that detects sound, and an output unit that outputs information regarding a position of the detection unit relative to a target apparatus which is a target to detect the sound by the detection unit.

Abstract: A terminal device including a detection unit that detects a sound, and an output unit that outputs information regarding a detection method of detecting the sound by the detection unit.

Abstract: A terminal device includes a detection unit that detects sound, and an output unit that outputs information regarding a position of the detection unit relative to a target apparatus which is a target to detect the sound by the detection unit.

Abstract: The estimation of an amount of chromatic dispersion using a training signal sequence is possible. A transmission method includes: a training signal sequence generation step of generating, as training signal sequences, a plurality of signal sequences having power concentrated in a plurality of frequency bands, the power concentrated at different frequency bands; a training signal sequence selection step of selecting at least one training signal sequence from among the plurality of training signal sequences generated in the training signal sequence generation step, a signal multiplexing step of generating a signal sequence obtained by time-division multiplexing the training signal sequence selected in the training signal sequence selection step with a transmission data sequence, and an electrical-to-optical conversion step of transmitting the signal sequence generated in the signal multiplexing step as an optical signal.

Abstract: An optical signal transmission apparatus includes a modulation unit which modulates a transmission signal, a training signal sequence generation unit which generates a plurality of signal sequences having power concentrated in a plurality of different frequency bands, at least one of an amplitude and a phase of the plurality of signal sequences being modulated, as a training signal sequence, a signal multiplexing unit which appends the training signal sequence to the transmission signal, and an electro-optical conversion unit which converts a signal sequence obtained by appending the training signal sequence to the transmission signal into an optical signal and transmits the optical signal.

Abstract: A switch circuit includes: a sampling transistor including a source connected to an input node and a drain connected to an output node; a control circuit which is connected to a gate of the sampling transistor and configured to control turning on or off of the sampling transistor; a voltage holding circuit which is provided between the gate and the source of the sampling transistor and configured to maintain a voltage between the gate and the source of the sampling transistor constant when the sampling transistor is turned on; and a protection circuit which is provided in parallel to the control circuit and configured to lower a voltage that is applied to the gate of the sampling transistor when the sampling transistor makes a transition from on to off.

Abstract: A switch circuit includes: a sampling transistor including a source connected to an input node and a drain connected to an output node; a control circuit which is connected to a gate of the sampling transistor and configured to control turning on or off of the sampling transistor; a voltage holding circuit which is provided between the gate and the source of the sampling transistor and configured to maintain a voltage between the gate and the source of the sampling transistor constant when the sampling transistor is turned on; and a protection circuit which is provided in parallel to the control circuit and configured to lower a voltage that is applied to the gate of the sampling transistor when the sampling transistor makes a transition from on to off.

Abstract: An increase in circuit scale is suppressed and a phase variation caused in a transmission path or the like is compensated for.

Abstract: The estimation of an amount of chromatic dispersion using a training signal sequence is possible. A transmission method includes: a training signal sequence generation step of generating, as training signal sequences, a plurality of signal sequences having power concentrated in a plurality of frequency bands, the power concentrated at different frequency bands; a training signal sequence selection step of selecting at least one training signal sequence from among the plurality of training signal sequences generated in the training signal sequence generation step, a signal multiplexing step of generating a signal sequence obtained by time-division multiplexing the training signal sequence selected in the training signal sequence selection step with a transmission data sequence, and an electrical-to-optical conversion step of transmitting the signal sequence generated in the signal multiplexing step as an optical signal.

Abstract: When a key depression speed and a key release speed of a key is to be detected based on a value of a counter (44) which accumulates a value every time the key passes through key switches (SW1, SW2), a number of digits of data indicating the key depression speed, a unit of the data being a bit and a number of digits of data indicating the key release speed, a unit of the data being a bit, are made the same.

Abstract: When a key depression speed and a key release speed of a key is to be detected based on a value of a counter (44) which accumulates a value every time the key passes through key switches (SW1, SW2), a number of digits of data indicating the key depression speed, a unit of the data being a bit and a number of digits of data indicating the key release speed, a unit of the data being a bit, are made the same.

Abstract: An electro-magnetic device assembly constituted of an electro-magnetic device; a chassis arranged to sink heat; at least one thermally conductive material in thermal communication with the electro-magnetic device and with the chassis; and at least one mechanically isolating material in contact with the thermally conductive material and with the chassis, the at least one mechanically isolating material arranged to dampen the transmission of vibrations experienced by the chassis, in the direction of the magnetic field of the electro-magnetic device, to the electro-magnetic device.