WO2011023723A1

WO2011023723A1 - Wireless microphone unit, wireless pocket transmitter and method for wireless audio transmission

Info

Publication number: WO2011023723A1
Application number: PCT/EP2010/062397
Authority: WO
Inventors: Claus Menke; Sven Boetcher; Wolfgang Niehoff; Björn WOLTER
Original assignee: Sennheiser Electronic Gmbh & Co. Kg
Priority date: 2009-08-25
Filing date: 2010-08-25
Publication date: 2011-03-03
Also published as: DE102009038521A1; DE102009038521B4

Abstract

The invention relates to a wireless microphone unit, provided with an input terminal (EA) for receiving an audio signal (AS) detected by a microphone capsule (ME), an embedding unit (ZCE) for embedding a time code (ZC) in the detected audio signal (AS1) and for outputting a first audio signal (AS1) having an embedded time code (ZC), and a data reduction unit (DRE) for carrying out data reduction (AS2) of the first audio signals (AS1) and for outputting second data-reduced audio signals (AS2). The wireless microphone unit further comprises a memory unit (SP) for storing the first audio signals (AS1), a transmitter (SE) for wirelessly transmitting the first or second audio signal (AS1; AS2), and a return link receiver (RSE) for receiving transmission terms of the transmission of the first or second audio signal (AS1; AS2) from the transmitter (SE) to an external receiver and/or setting information or setting parameters. The data reduction unit (DRE) is designed to perform data reduction of the first audio signal (AS2) depending on the setting information or parameters received from the return link receiver (RSE). The transmitter (SE) is designed to transmit the first audio signal (AS1) or the second audio signal (AS2) wirelessly on the basis of the information received via the return link receiver (RSE).

Description

Wireless microphone unit, wireless bodypack transmitter and wireless audio transmission method

The invention relates to a wireless microphone unit, a wireless pocket transmitter and a method for wireless audio transmission.

In wireless audio transmission, e.g. With wireless microphone systems, due to the increasing frequency occupancy, increased interference or interferences may occur.

It is therefore an object of the present invention to provide a wireless microphone unit, a wireless pocket transmitter and a method for wireless audio transmission, which allows a flexible handling of interference or interference of the audio transmission. This object is achieved by a wireless microphone unit according to claim 1, by a wireless pocket transmitter according to claim 8 and by wireless audio transmission method according to claim 8.

Thus, a wireless microphone unit having an input terminal for receiving an audio signal detected by a microphone capsule, an embedding unit for embedding a time code in the detected audio signal and outputting a first audio signal with embedded time code, a data reduction unit for performing data reduction of the first audio signals, and the Output of second data-reduced audio signals provided. The wireless microphone unit further has a memory unit for storing the first audio signals, a transmitting unit for wirelessly transmitting the first or second audio signals, and a return path receiving unit for receiving transmission conditions of transmission of the first or second audio signal from the transmitting unit to an external receiving unit and / or setting information or setting parameters. The transmitting unit SE is configured to wirelessly transmit the first or the second audio signal, wherein the selection of whether the first or second audio signal is transmitted based on the Recombined Empfaπgseinheit received information takes place. The data reduction unit is configured to perform a data reduction of the first audio signal as a function of the adjustment information or parameters received by the return link receiving unit. According to one aspect of the present invention, there is further provided an analog-to-digital converting unit for analog-to-digital converting the detected audio signal.

According to a further exemplary embodiment of the invention, the embedding unit is designed to embed metadata and / or data reduction parameters in the audio signal. According to a further aspect of the present invention, a readout output is provided for reading out the audio signals stored in the memory unit.

According to a further aspect of the present invention, at least one electroacoustic microphone capsule is provided for detecting audio signals.

According to another aspect of the present invention, the return link receiving unit is configured to receive an external time code and to receive setting information and / or parameters.

The invention also relates to a wireless pocket transmitter, wireless hand-held transmitter or wireless camera transmitter. The wireless transmitter has an input port for receiving a detected audio signal, an embedding unit for embedding a time code in the detected audio signal and outputting a first time-code embedded audio signal. The transmitter further comprises a data reduction unit for performing a data reduction of the first audio signals and for outputting second data-reduced audio signals. The transmitter further comprises a memory unit for storing the first audio signals and a transmitting unit for wireless transmission of the first or second audio signals. Furthermore, the wireless transmitter has a return path receiving unit for receiving transmission conditions of transmission of the first or second audio signal from the transmitting unit to an external receiving unit and / or setting information and / or setting parameters. The transmitting unit is configured to wirelessly transmit the first or the second audio signal. The choice of whether the first or second audio signal is transmitted wirelessly is carried out based on the information received via the return link receiving unit. The data reduction unit is configured to perform a data reduction of the first audio signal as a function of the setting information and / or parameters received by the return link receiving unit. The invention also relates to a method for wireless audio transmission. A detected audio signal is received and a time code is embedded in the detected audio signal, and a first audio signal having the embedded time code is output. A data reduction of the first audio signals is performed and second data-reduced audio signals are output. The first audio signals are stored in the memory. The first or second audio signals are sent wirelessly. Transmission conditions of transmission of the first or second audio signal to an external receiving unit, setting information or setting parameters are received. A data reduction of the first audio signals takes place as a function of the received setting information and / or parameters. The selection as to whether the first or second audio signal is transmitted for wireless transmission is based on the received information.

According to the invention, a quality-adapted wireless audio transmission can be provided, wherein the recorded audio signals can be stored without or with a lower data reduction and subsequently processed further. If a time code or a time stamp is embedded in both the wirelessly transmitted and the stored audio signals, then these audio signals may be mixed in a downstream audio processing when e.g. in the wireless audio transmission has come to errors or failures.

With the data reduction unit, different conditions (transmission speed, bandwidth, etc.) in the audio transmission can be addressed by adapting the data reduction to the transmission conditions.

Further embodiments of the invention are the subject of the dependent claims. Features described in the subclaims can be arbitrarily combined with features from other subclaims. Embodiments and advantages of the invention will be described in more detail with reference to the drawing. - A -

Fig. 1 shows a block diagram of a wireless microphone unit according to a first embodiment of the invention.

Fig. 1 shows a block diagram of a wireless microphone unit according to a first embodiment of the invention. The microphone unit optionally comprises a microphone capsule ME for recording audio signals (ie converting acoustic signals into electrical signals), an input terminal EA for receiving the audio signals AS recorded by the microphone capsule ME, an embedding unit ZCE for embedding a time code or a time stamp ZC in the recorded audio signals AS and outputting first audio signals AS1 with embedded time code, an (audio) memory unit SP for storing the audio signals with embedded time code (ie the first audio signals AS1), optionally a data reduction unit DRE for performing a data reduction the recorded audio signals AS1 with embedded time code ZC and for outputting data-reduced or compressed audio signals (second audio signals AS2). The microphone unit ME furthermore has a wireless transmission unit SE for wireless transmission of the optionally data-reduced or compressed second audio signals (with embedded time code ZC) to an external reception unit EE (not shown).

The microphone unit also has a return path receiving unit RSE for receiving information and / or parameters of the wireless transmission path. This information and / or parameters may be e.g. the bit error rate BER or the signal-to-noise ratio of the transmission, an external time code (e.g., from the external receiving unit), a transmission frequency change instruction, a command to apply a specific compression method and its parameters, or the like. Optionally, the microphone unit may comprise an analog-to-digital converter unit ADE at the input terminal EA for analog-to-digital conversion of the recorded audio signals. If the recorded audio signals already represent digital audio signals, the ADE converter unit can optionally be dispensed with.

The information received by the return link receiving unit RSE may be used in the embedding unit ZCE for embedding in the recorded audio signal AS. Alternatively, an internal character code ZC may be used. This internal character code ZC can also be sent to the external receiving be transmitted unit. This transmission can be done by the transmitting unit SE or by another transmitting unit, for example by an IR, HF, Bluetooth, WiFi transmission.

The bit error rate BER received by the return link receiving unit RSE may be used in the data reducing unit DRE to control the execution of the data reduction or the compression. Thus, the data reduction or the compression is adapted to the characteristics or conditions of the transmission path of the wireless audio transmission.

Receives the wireless microphone unit via the return path receiving unit RSE the information that due to current disturbances, the maximum attainable data rate of the wireless transmission on the available channel is not sufficient to transmit the full audio signal AS1, the compression method is configured so that the compressed audio signal AS2 is compressed so much that it can be transmitted wirelessly with the currently available data rate. A deterioration of the audio quality of the wirelessly transmitted audio signal AS2 due to the compression is accepted.

In the (audio) memory SP, the first audio signals AS1 (with embedded time code) can be stored. Optionally, the data may be stored in a compressed form in the memory SP to increase the duration of the recording, which is possible with the available storage space. Unlike the compression that takes place in the data reduction unit DRE for immediate wireless transmission, a time offset until storage in the memory SP is not critical. For storage in the memory SP, therefore, "block-based" compression methods can be used in which initially a larger amount of samples is collected, and then to compress the entire block contiguous. For the data in the memory SP can thus be selected lossless compression. In order to further increase the duration of the recording in the memory SP, lossy compression methods can alternatively also be used here. According to the invention, the recorded audio signals can be stored in a better and, in particular, consistent quality in the memory SP than the quality with which the wireless transmission takes place. This is particularly advantageous for subsequent processing of the recorded audio signals. The storage of the recorded audio signals in the memory unit SP can optionally take place in an endless loop. The above-described memory unit SP may, for example, perform the storage of the recorded audio signals in a loop method. The storage unit can both be fixedly arranged in the microphone unit or can be an exchangeable storage unit. In the transmitted by the return path from a receiver to the microphone unit information and / or parameters, for example, the frequency of the radio transmission used and an instruction to change the frequency may be included. Here, for example, the new frequency can be transmitted.

If a plurality of parallel radio links (transmission from the microphone unit to an external receiver) is used, then a plurality of external receiving units can be provided, which can be networked with each other, for example. This is particularly advantageous because changes made to a radio link are logged, provided with a time stamp and stored accordingly. The change made can also be forwarded to the other microphone units, so that they can also be adjusted to the new settings.

According to a further embodiment of the invention, a combined charging and storage unit for the microphone unit can be provided, wherein the information stored in the microphone unit is extracted via the output terminal AA and forwarded to a downstream processing system. Changes made during the transmission of the transmission parameters can be visualized, for example, in the downstream processing system.

The external receiving unit described above may for example represent a receiving unit, which is connected to a mixer or integrated in the mixer.

The data reduction unit DRE can perform a data reduction of the recorded audio signals in dependence on the information and / or parameters received by the return path receiving unit RSE. Alternatively, the data reduction unit DRE can also perform a data reduction independently of this received information. The transmitting unit SE can be configured to transmit the current transmission mode and / or transmission parameters to the external receiving unit.

The external receiving unit can be configured to log or store both the transmitted audio signals and the likewise transmitted information and / or parameters.

Optionally, the microphone unit can have a time unit ZE, which is synchronized on the basis of the time code or time stamp. This can be advantageous, because it enables a time stamp independent of the external receiving unit. The reception of the time code or the time stamp from the external receiving unit then serves only to synchronize the time unit ZE already present.

According to a further embodiment of the invention, the storage of the recorded audio signal in the memory unit SP can be controlled in dependence on the information and / or parameters received by the return path receiving unit RSE. Thus, for example, it can be controlled by an external receiving unit, in which quality the recorded audio signals are stored in the memory unit SP.

Saving in the loop method preserves the last recorded audio signals recorded, while initially overwriting the oldest recorded audio signals. The recording time can be controlled by the external receiving unit.

According to a second embodiment, a wireless bodypack transmitter, wireless hand-held transmitter or wireless camera transmitter is provided. The transmitters according to the second embodiment are essentially based on the first embodiment, wherein the input terminal is used for receiving detected audio signals. Otherwise, the structure according to the second embodiment corresponds to the structure according to the first embodiment.

To a wireless pocket transmitter, for example, an external microphone and / or a

Musical instrument to be connected. The same applies to the wireless remote control. A wireless camera transmitter is preferably attached to a camera and may receive detected audio signals from, for example, the camera or from an input port.

According to a further embodiment of the invention, which may be based on the first embodiment, there is no embedding of a time code in the detected signal. Thus, the detected signal without time code is stored in the memory SP and compressed by the data reduction unit DRE. Alternatively, the time code may be embedded only for the data to be stored in the memory SP, so that the data reduction unit DRE performs compression of the data without time code. Alternatively, the detected signals without embedded time code may be stored in the memory SP while the data having the embedded time code is supplied to the data reduction unit DRE for compression.

Claims

claims

1. Wireless microphone unit, with

an input terminal (EA) for receiving an audio signal (AS) detected by a microphone capsule (ME),

an embedding unit (ZCE) for embedding a time code (ZC) in the detected one

Audio signal (AS1) and for outputting a first audio signal (AS1) with embedded time codes (ZC),

a data reduction unit (DRE) for performing a data reduction of the first audio signals (AS1) and for outputting second data-reduced audio signals (AS2),

a memory unit (SP) for storing the first audio signals (AS1), a transmission unit (SE) for the wireless transmission of the first or second audio signals (AS1, AS2),

a return path receiving unit (RSE) for receiving transmission conditions of the transmission of the first or second audio signal (AS1, AS2) from the transmitting unit (SE) to an external receiving unit and / or setting information and / or setting parameters,

wherein the transmitting unit (SE) is configured to wirelessly transmit the first audio signal (AS1) or the second audio signal (AS2) based on the information received via the return link receiving unit (RSE) and

wherein the data reduction unit (DRE) is configured to perform a data reduction of the first audio signal (AS1) in dependence on the setting information and / or parameter received by the return link receiving unit (RSE).

2. Wireless microphone unit according to claim 1, further comprising

an analog-to-digital converter unit (ADE) for analog-to-digital conversion of the acquired audio signal (AS).

3. Wireless microphone unit according to claim 1 or 2,

wherein the embedding unit (ZCE) is adapted to embed metadata and / or data reduction parameters in the audio signal (AS).

4. Wireless microphone unit according to one of claims 1 to 3, further comprising a readout output (AA) for reading the stored in the memory unit (SP) audio signals with time code (ZC).

5. Wireless microphone unit according to one of claims 1 to 3, further comprising

at least one electroacoustic microphone capsule (ME) for detecting audio signals (AS).

6. A wireless microphone unit according to any one of claims 1 to 5, wherein the return path receiving unit (RSE) is configured to receive an external time code (ZC) and to receive setting information and / or parameters.

A wireless pocket transmitter, wireless transmitter or wireless camera transmitter, having an input terminal (EA) for receiving a detected audio signal (AS),

an embedding unit (ZCE) for embedding a time code (ZC) in the detected audio signal (AS1) and for outputting a first audio signal (AS1) with embedded time codes (ZC) ₁

a memory unit (SP) for storing the first audio signals (AS1), a transmission unit (SE) for wireless transmission of the first or second audio signals (AS 1; AS2),

wherein the data reduction unit (DRE) is configured to perform a data reduction of the first audio signal (AS1) as a function of the setting information and / or parameter received by the return link receiving unit (RSE).

8. Method for wireless audio transmission with the steps:

Receiving a detected audio signal,

Embedding a time code in the detected audio signal and outputting a first audio signal with embedded time codes,

Performing a data reduction of the first audio signals and outputting second data-reduced audio signals,

Storing the first audio signals,

wireless transmission of the first or second audio signals,

Receiving transmission conditions of transmission of the first or second audio signal to an external receiving unit and / or setting information or setting parameters, and

Performing the data reduction of the first audio signal in dependence on the received setting information and / or parameter,

wherein the selection whether the first audio signal (AS1) or the second audio signal (AS2) is transmitted for wireless transmission is based on the received information.