An optical network element includes a connection to an optical fiber in an optical line system including a coherent receiver; a microphone configured to detect sound; and circuitry connected to the microphone and configured to cause transmission of information related to sounds detected by the microphone to a receiver at an end of the optical line system, wherein the transmission is over the optical fiber in the optical line system to the coherent receiver. The optical network element can include a polarization controlling device connected to the circuitry and configured to modulate a state-of-polarization (SOP) envelope for the transmission.

A method includes receiving a signal having a telemetry portion and a noise portion. The method may also include identifying one or more harmonic frequencies in the signal. The method may also include determining whether the one or more harmonic frequencies are in a predetermined frequency band. The method may also include determining whether a signal-to-noise ratio (SNR) of the signal is below a predetermined SNR threshold. The method may also include generating one or more notifications in response to the determination whether the one or more harmonic frequencies are in the predetermined frequency band and the determination whether the SNR is below the predetermined SNR threshold.

A method includes receiving a signal having a telemetry portion and a noise portion. The method may also include identifying one or more harmonic frequencies in the signal. The method may also include determining whether the one or more harmonic frequencies are in a predetermined frequency band. The method may also include determining whether a signal-to-noise ratio (SNR) of the signal is below a predetermined SNR threshold. The method may also include generating one or more notifications in response to the determination whether the one or more harmonic frequencies are in the predetermined frequency band and the determination whether the SNR is below the predetermined SNR threshold.

A digital transmit beamformer for an ultrasound system has a waveform sample memory which stores sequences of samples of different pulse transmit waveforms of differing pulse widths. The memory is shared by a plurality of transmit channels, each of which can access its own selected sample sequence, independent of the selections by other channels. Waveform sample readout by the channels occurs substantially simultaneously during a transmit event, producing a transmit beam from a transmit aperture with different pulse waveforms applied to different elements of the transmit aperture. Higher energy waveforms with wider pulse widths are applied to central elements of the aperture and lower energy waveforms with narrower pulse widths are applied to lateral elements of the aperture to produce an apodized transmit beam.

A digital transmit beamformer for an ultrasound system has a waveform sample memory which stores sequences of samples of different pulse transmit waveforms of differing pulse widths. The memory is shared by a plurality of transmit channels, each of which can access its own selected sample sequence, independent of the selections by other channels. Waveform sample readout by the channels occurs substantially simultaneously during a transmit event, producing a transmit beam from a transmit aperture with different pulse waveforms applied to different elements of the transmit aperture. Higher energy waveforms with wider pulse widths are applied to central elements of the aperture and lower energy waveforms with narrower pulse widths are applied to lateral elements of the aperture to produce an apodized transmit beam.

The multiplexer includes a plurality of IDT electrodes on a substrate, an insulating cover located on the substrate so as to configure one or more spaces above the plurality of IDT electrodes, an antenna terminal, transmission terminal, and reception terminal which are all located on the substrate and pass through the cover, and a reinforcing layer which is located on the cover and is made of metal. By the plurality of IDT electrodes, a transmission filter located in a signal path connecting the antenna terminal and the transmission terminal and a receiving filter located in a signal path connecting the antenna terminal and the reception terminal. The reinforcing layer includes a first area part facing the transmission filter and a second area part which faces the receiving filter and is separated from the first area part.

The multiplexer includes a plurality of IDT electrodes on a substrate, an insulating cover located on the substrate so as to configure one or more spaces above the plurality of IDT electrodes, an antenna terminal, transmission terminal, and reception terminal which are all located on the substrate and pass through the cover, and a reinforcing layer which is located on the cover and is made of metal. By the plurality of IDT electrodes, a transmission filter located in a signal path connecting the antenna terminal and the transmission terminal and a receiving filter located in a signal path connecting the antenna terminal and the reception terminal. The reinforcing layer includes a first area part facing the transmission filter and a second area part which faces the receiving filter and is separated from the first area part.

A system configured for vehicle communication includes a first smart apparatus associated with a first vehicle having a first horn and configured to acquire a first target information and a transmission direction information; a first horn control portion embedded in the first vehicle and configured to control the first horn in the first vehicle to send a first sound wave signal modulated by the first target information to a second vehicle based on the transmission direction information; and a second smart apparatus associated with the second vehicle and configured to receive the first sound wave signal and demodulate the first sound wave signal to obtain the first target information.

A sound field generation apparatus includes: a first modulation unit 10 that modulates an ultrasonic wave signal according to a prescribed modulation system; a second modulation unit 30 that modulates the ultrasonic wave signal ω.sub.0 according to a modulation system different from the modulation system of the first modulation unit 10; a filter unit 20 that changes frequency characteristics of an audible range signal s(t) used in modulation of the second modulation unit 30; a first ultrasonic wave output unit 40 that outputs a first ultrasonic wave signal y-(t) modulated by the first modulation unit 10; and a second ultrasonic wave output unit 50 that outputs a second ultrasonic wave signal y˜(t) modulated by the second modulation unit 30, wherein the filter unit 20 is set to have filter characteristics to cancel a first audible sound y-(t) reproduced by the first ultrasonic wave signal y-(t) with a second audible sound y˜(t) reproduced by the second ultrasonic wave signal y˜(t) at a control point 70 provided outside the sound field 60.

A sound field generation apparatus includes: a first modulation unit 10 that modulates an ultrasonic wave signal according to a prescribed modulation system; a second modulation unit 30 that modulates the ultrasonic wave signal ω.sub.0 according to a modulation system different from the modulation system of the first modulation unit 10; a filter unit 20 that changes frequency characteristics of an audible range signal s(t) used in modulation of the second modulation unit 30; a first ultrasonic wave output unit 40 that outputs a first ultrasonic wave signal y-(t) modulated by the first modulation unit 10; and a second ultrasonic wave output unit 50 that outputs a second ultrasonic wave signal y˜(t) modulated by the second modulation unit 30, wherein the filter unit 20 is set to have filter characteristics to cancel a first audible sound y-(t) reproduced by the first ultrasonic wave signal y-(t) with a second audible sound y˜(t) reproduced by the second ultrasonic wave signal y˜(t) at a control point 70 provided outside the sound field 60.