Abstract: A microphone is provided comprising a microphone capsule adapted to capture an audio signal, an AD converter configured to convert the captured audio signal into a digital signal, a block generator configured to divide the digital audio signal into a plurality of audio blocks, a private key signature unit configured to generate at least one signature based on at least one of the plurality of audio blocks with a private key associated to the microphone and an audio output configured to output the at least one audio block and the generated at least one signature.

Abstract: An IP based remote video conferencing system (100) comprises a near-end (200) having a first room (200a) and at least one microphone (210) configured to detect audio signals from at least one participant (201, 202) in the first room (200a) and to determine position information regarding the at least one first participant (201, 202), a far end (300) having a second room (300a) with at least one second participant (301) and at least one audio reproducer (330), wherein said at least one audio reproducer (330) receives and reproduces spatial audio signals based on the audio signals and the position information detected by the at least one microphone (210), and a video conferencing service (400) coupled to the near end (200) and the far end (300) configured to forward audio signals from the near end (200) to the far end (300).

Abstract: A mobile wireless receiver is provided comprising an HF input, an intermediate-frequency output, a first and second mixer, which are each operated in common mode with a frequency of a local oscillator, a first balun circuit, which is coupled to the HF input and a second balun circuit, which is coupled to the intermediate-frequency output, a first common mode trap, which is coupled to the first balun circuit and the first and second mixer and a second common mode trap, which is coupled to the second balun circuit and the first and second mixer.

Abstract: The wireless communication between a base station and a mobile device is frequently based on time division multiple access methods with time slots, some of which are provided for control information. A common time base must be used for this. Since each mobile device has its own time base, it must first of all detect and correct deviations from the time base of the base station. However, the radio signals have unknown and variable transit times. In order to improve the synchronisation of a mobile device with the base station, a mobile device transmits a first synchronisation signal to the base station at a time which, according to its time base, lies in a time slot for control information.

Abstract: For radio transmission via OFDM (Orthogonal Frequency Division Multiplex) and TDMA (Time Division Multiple Access), it is important to have at the receiver the exact carrier frequency, and further to perform time synchronization. For time synchronization and simultaneous detection of a carrier frequency offset, a complex-valued synchronization sequence such as e.g. a Zadoff-Chu-sequence is transmitted twice: first in its original version and then, after a predefined time span, in its complex conjugate version. At the receiver, the two corresponding correlation maxima are detected by cross-correlation, and the time span between the maxima is measured. The measured time span is compared to the predefined time span and a time offset is determined. The time offset can be used to improve the synchronization accuracy and to determine the carrier frequency offset.

Abstract: A hot-shoe adapter system is provided for fastening accessory parts to a hot shoe. The hot-shoe adapter system has a hot-shoe adapter with a first side for fastening in a hot shoe and a second side, and an adapter plate, which has a plurality of first holes for fastening the hot-shoe adapter, a plurality of second holes for fastening the second side of the hot-shoe adapter, four corners each with a third hole and at least one magnetic element in the region of the third holes.

Abstract: An IP based remote video conferencing system (100) comprises a near-end (200) having a first room (200a) and at least one microphone (210) configured to detect audio signals from at least one participant (201, 202) in the first room (200a) and to determine position information regarding the at least one first participant (201, 202), a far end (300) having a second room (300a) with at least one second participant (301) and at least one audio reproducer (330), wherein said at least one audio reproducer (330) receives and reproduces spatial audio signals based on the audio signals and the position information detected by the at least one microphone (210), and a video conferencing service (400) coupled to the near end (200) and the far end (300) configured to forward audio signals from the near end (200) to the far end (300).

Abstract: In radio networks having a plurality of access points, for example WiFi, a wireless audio end device like for example a microphone or headphones is connected to an access point, to which it sends its audio data or from which it receives same. Audio transmission should occur as far as possible in interruption-free manner and with low latency. If the audio end device is moved the connection quality in relation to the previous access point can decrease and require scanning or roaming. In that respect first another base station is sought and then the radio connection is redirected there. In order in that case to avoid disruptive signal interruptions portions of the audio signal which can be particularly well predicted are detected or predicted by means of short-term statistical methods, like for example speech pauses. Scanning and roaming are then carried out during the predicted portions, whereby interruptions which are perceptible to a user are avoided.

Abstract: Embodiments of the invention provide for methods for automatically controlling loudness of an audio signal. Embodiments of the invention also provide for a device for automatically controlling loudness of an audio signal. In particular, the invention relates to controlling loudness of an audio signal to be replayed within a vehicle, such as a car.

Abstract: A loudspeaker power amplifier comprising a digital amplifier is provided. The amplifier has a negative input and a positive input as well as a negative output and a positive output. The power amplifier further comprises a first feedback circuit from the positive output to the negative input, and a second feedback circuit from the negative output to the positive input. The first and the second feedback circuit each have a first and a second amplification circuit.

Abstract: An electret microphone is provided. This comprises an electrically conductive membrane, and a counter-electrode having at least one first hole having a first distance from an edge of the counter-electrode and a second plurality of second holes each having a second distance from the edge of the counter-electrode. The second distance is shorter than the first distance. The electret microphone has a first electrically conductive coating on a first side of the counter-electrode and a second electrically conductive coating on a second side of the counter-electrode. The at least one first hole comprises a via in order to electrically contact the first and second electrically conductive coating. A third distance is provided in each case between the second holes and the first electrically conductive coating so that the first electrically conductive coating does not reach as far as the second holes.

Abstract: A mobile wireless audio transmission system is provided, comprising at least one mobile wireless transmitter for the wireless transmission of audio signals which have been recorded via a microphone in the transmitter or which have been transmitted via an audio input to the transmitter. The transmitter comprises a transmitter rechargeable battery unit. The system further comprises a mobile wireless receiver for the wireless reception of audio signals transmitted wirelessly by the at least one transmitter, wherein the receiver comprises a receiver rechargeable battery unit. The system further comprises a mobile charging/transport dock which comprises at least one transmitter receiving compartment for receiving a transmitter and a receiver receiving compartment for receiving a receiver and a rechargeable battery unit as power supply.

Abstract: An electret microphone is provided, comprising a microphone capsule with an output connection, a first input connection as an earth connection and a second input connection for providing a supply voltage for the microphone capsule and for leading out a microphone output signal of the microphone capsule, and a cascode consisting of a first and second transistor. An output connection of the microphone capsule is provided as input of the cascode. The second transistor is configured as a field effect transistor FET and the gate connection thereof is coupled to the output connection of the microphone capsule. A drain connection of the second transistor is coupled to an emitter connection of the first transistor as bipolar transistor or to a source connection of the first transistor as an FET transistor. Furthermore, a third transistor is provided as bipolar transistor, whose emitter connection is coupled to the second input connection.

Abstract: Microphone capsules for condenser or electret microphones often exhibit individual deviations from a desired ideal behavior, e.g. the frequency response and phase response. Particularly if a plurality of microphone capsules are interconnected to form a microphone array, suitable microphone capsules must be found in a selection process. Some of these deviations can be corrected electronically, e.g. by filtering with a corresponding filter that is individually adapted. An improved microphone capsule, with which an automatic selection and automatic assembly of circuit boards with microphone capsules is facilitated, comprises an electrostatic sound transducer, an amplifier element that outputs an amplified output signal of the electrostatic sound transducer, and at least one electronic memory element. Data obtained by a measurement and relating to the individual frequency response or phase response of the respective microphone capsule can be stored therein.

Abstract: A microphone array system or microphone array unit for a conference system is provided that includes a front board, side walls and a plurality of microphone capsules arranged in or on the front board mountable on or in a ceiling of a conference room. The microphone array system or unit is adapted for generating a steerable beam within a maximum detection angle range. The microphone array system or microphone array unit includes a processing unit which is configured to receive the output signals of the microphone capsules and to steer the beam based on the received output signal of the microphone array. The processing unit is configured to control the microphone array to limit the detection angle range to exclude at least one predetermined exclusion sector in which a noise source is located.

Abstract: Microphone arrays comprise several microphone capsules, the outputs of which being electronically combined for directional recording of sound. The directional and frequency properties of the microphone array depend on the number and positions of the microphone array. In order to obtain the smallest possible microphone array with only few microphone capsules, which, however, has an essentially uniform directional and frequency dependence over a speech frequency range, is scalable and robust against small incorrect positioning of the capsules, fifteen or twenty-one microphone capsules (K15,11 - K15,35, K21,11 - K21,37) are arranged on a carrier such that they lie on three similar branches, each with the same number of microphone capsules, which are rotated against each other by 120°. Each of the microphone capsules lies on a corner of a triangle of a grid in a flat isometric coordinate system with three axes rotated by 60° against each other and forming the grid_of equilateral triangles.

Abstract: A microphone array system or microphone array unit for a conference system is provided that includes a front board, side walls and a plurality of microphone capsules arranged in or on the front board mountable on or in a ceiling of a conference room. The microphone array system or unit is adapted for generating a steerable beam within a maximum detection angle range. The microphone array system or microphone array unit includes a processing unit which is configured to receive the output signals of the microphone capsules and to steer the beam based on the received output signal of the microphone array. The processing unit is configured to control the microphone array to limit the detection angle range to exclude at least one predetermined exclusion sector in which a noise source is located.

Abstract: A microphone array device including microphone capsules and at least one processing unit configured to receive output signals of the microphone capsules, dynamically steer an audio beam based on the received output signal of the microphone capsules, and generate and provide an audio output signal based on the received output signal of the microphone capsules. The processing unit is configured to operate in a dynamic beam mode where at least one focused audio beam is formed that points towards a detected audio source and in a default beam mode where a broader audio beam is formed that covers substantially a default detection area. The microphone array may be incorporated into a conference system.

Abstract: Microphone arrays comprise several microphone capsules, the outputs of which being electronically combined for directional recording of sound. The directional and frequency properties of the microphone array depend on the number and positions of the microphone array. In order to obtain the smallest possible microphone array with only few microphone capsules, which, however, has an essentially uniform directional and frequency dependence over a speech frequency range, is scalable and robust against small incorrect positioning of the capsules, fifteen or twenty-one microphone capsules (K15,11-K15,35, K21,11-K21,37) are arranged on a carrier such that they lie on three similar branches, each with the same number of microphone capsules, which are rotated against each other by 120°. Each of the microphone capsules lies on a corner of a triangle of a grid in a flat isometric coordinate system with three axes rotated by 120° against each other and forming the grid of equilateral triangles.