A device for deciding characteristics of a differential signal cable at a transmission rate of not less than 10 G baud includes a selector switch that changes a transmission rate or an output power of a test signal to be supplied to the differential signal cable, a signal transmitting circuit that generates a test signal at a different transmission rate or output power as one of the predetermined number of plurality of test signals according to the change of state of the selector switches and sends the generated test signal to the differential signal cable via one connector, and a signal receiving circuit that receives the test signal transmitted through the differential signal cable via the other connector and decides the success or failure of transmission of the test signal through the differential signal cable based on the received test signal and pre-stored data of the plurality of test signals.

The technology described in this document can be embodied in a first acoustic device that includes an input port configured to receive an input signal representing audio from a media device, and one or more acoustic transducers. The first acoustic device also includes one or more processors configured to generate, from the input signal, a first signal for producing an acoustic output from the one or more transducers, and a second signal for producing an acoustic output from a second acoustic device. The first and second signals are generated from the input signal based on a feedback signal received from the second acoustic device. The first acoustic device also includes an output port for providing a portion of the second signal to the second acoustic device.

A broadband powerline communication system is disclosed which makes use of knowledge of the spectrum characteristics of a local radio environment in order to improve the performance of the system. A determination is made of the spectrum characteristics of a radio environment in the vicinity of the broadband powerline communication system that is transmitting data on modulated carrier frequencies. Certain ones of the carrier frequencies otherwise used by the broadband powerline communication system may be masked (i.e., not used) by all or part of the broadband powerline system in order to avoid interference based on the determination. In various embodiments, the spectrum characteristics are determined 1) in advance and used to compile a configuration database comprising frequency masking parameters; 2) by monitoring the local radio environment using the transmitter/receiver nodes of the system; or 3) based upon receipt of an indication from a conflicting user that the user is experiencing interference. Various combinations of these spectrum characteristic determination techniques may also be used.

A driver circuit for driving a transmission line, such as a cable or a metal trace on a printed circuit board is described. The driver may be configured to drive lines with voltages exceeding the maximum voltage than a transistor can withstand for a given fabrication node. The driver may be configured to receive a supply voltage larger than that indicated by manufacturers. The driver may use a fast path and a slow path. Signals provided by the slow path and the fast path may be combine to adapt the input signals to levels that do cause stress to a transistor. A plurality of drivers of the type described herein may be used to provide digital-to-analog conversion.

A system for coupling a modulated voltage signal onto a current loop between a host device and a field device, in various embodiments, can include a circuit and an impedance bridge. The circuit is configured to flow current from the field device between two terminals of an input circuit in the host device, wherein the two terminals are included in the current loop. The impedance bridge is positioned between the two terminals and configured to modulate impedance to convert the current in a field loop produced by the field device into terminal voltage modulation, without introducing a DC voltage burden to the current.

A system for coupling a modulated voltage signal onto a current loop between a host device and a field device, in various embodiments, can include a circuit and an impedance bridge. The circuit is configured to flow current from the field device between two terminals of an input circuit in the host device, wherein the two terminals are included in the current loop. The impedance bridge is positioned between the two terminals and configured to modulate impedance to convert the current in a field loop produced by the field device into terminal voltage modulation, without introducing a DC voltage burden to the current.

A circuit for compensation of baseline voltage wander operating at an input of an isolator is disclosed. The circuit can compensate electronically the frequency response of an isolation circuit (e.g., a transformer) by increasing the pass band in the low frequency region in order to minimize the baseline wander caused by low inductance windings. The compensation circuit can be used to inject a current ramp proportional to the amplitude and the duration of the pulse and inversely proportional to the open circuit inductance of the isolation circuit.

The present invention relates to a wireless speaker arrangement. The present invention also relates to a wireless speaker system comprising at least a pair of such speaker arrangements, to a method for operating a wireless speaker arrangement and to a corresponding computer program product.

An aircraft flight deck audio system, including a central management unit and pilot, co-pilot and third-man terminals. Estimation units estimate the quality of uplink and/or downlink digital signals of the pilot and co-pilot terminals. A control unit is configured such that, when the quality of the digital signals on the uplink and/or the downlink of the pilot or co-pilot terminal is estimated as unsatisfactory, the digital signals intended for the pilot or co-pilot terminal are routed toward the third-man terminal downlink and the digital signals originating from the third-man terminal and present on the uplink are routed toward the output of the pilot or co-pilot terminal. Transceiver units of the pilot, co-pilot and third-man terminals, respectively, transmit the digital signals of the pilot or co-pilot terminal on the third-man terminal downlink and the digital signals on the uplink of the third-man terminal toward the pilot or co-pilot terminal.

Aspects of the subject disclosure may include, for example, a system for receiving first electromagnetic waves via a transmission medium without utilizing an electrical return path, and inducing second electromagnetic waves at an interface of the transmission medium without the electrical return path. In an embodiment, the first and second electromagnetic waves have a non-optical frequency range. Other embodiments are disclosed.