419 results about "Digital audio broadcasting" patented technology

A method is provided for synchronizing the playback of a digital audio broadcast on a plurality of network output devices by inserting an audio waveform sample in an audio stream of the digital audio broadcast. The method includes the steps of outputting a first unique signal as part of an audio signal which has unique identifying characteristics and is regularly occurring, outputting a second unique signal so that the time between the first and second unique signals must be significantly greater than the latency between sending and receiving devices, and coordinating play of audio by an audio waveform sample assuring the simultaneous output of the audio signal from multiple devices. An algorithm in hardware, software, or a combination of the two identifies the audio waveform sample in the audio stream. The digital audio broadcast from multiple receivers does not present to a listener any audible delay or echo effect.

A method is provided for synchronizing the playback of a digital audio broadcast on a plurality of network output devices using a microphone near a source, embedded control codes, and the audio patterns from the network output devices. An optional, additional manual adjustment method relies on a graphical user interface for adjustment and audible pulses from the devices which are to be synchronized. Synchronization of the audio is accomplished with clock synchronization of the network output devices. The digital audio broadcast from multiple receivers does not present to a listener any audible delay or echo effect.

A method is provided for synchronizing the playback of a digital audio broadcast on a plurality of network output devices by inserting a control track pulse in an audio stream of the digital audio broadcast. The method includes the steps of outputting a first control track pulse as part of an audio signal which has unique identifying characteristics and is regularly occurring, outputting a second control track pulse so that the time between the first and second control track pulses must be significantly greater than the latency between sending and receiving devices, and coordinating play of audio at the time of the occurrence of the transmission of the second control track pulse assuring the simultaneous output of the audio signal from multiple devices. The control track pulses have a value unique from any other portion of the audio stream. The digital audio broadcast from multiple receivers does not present to a listener any audible delay or echo effect.

A method and apparatus for supporting a priority transmission of broadcasting data in a transmitter of a digital broadcasting system. A determination is made as to whether a priority transmission of one broadcasting service to be provided is supported. If the service supports the priority transmission, a plurality of subchannels to be transmitted for the service are set and a priority of the data to be mapped to the plurality of subchannels is set. The data of the broadcasting service is mapped to the plurality of subchannels according to the priority. Data streams mapped to the plurality of subchannels are encoded in different encoders and the encoded data streams are transmitted.

The present invention provides a system and method for introducing white noises into a digital audio signal so that there is progressive and cumulative degradation in audio quality after each successive reproduction of the audio sound signal in a fashion analogous to analog audio reproduction. The invention provides a white noise generator, and a digital entroping unit. In a preferred embodiment, the white noise generator is implemented by a hardware random number generator. The digital entroping unit controls the magnitude of white noise desired based on a random number generated by the random number generator, and adds the white noise to the input audio sound signal to produce a degraded audio sound signal. The magnitude of white noise can be controlled by using various masking and formatting of random number data.

The present invention relates to a subchannel structure within a main service channel for transmitting data of at least one application in a digital audio broadcasting system, such as DAB or DRM. Further methods for transmitting and receiving application data using the subchannel structure, as well as a corresponding broadcasting station and receiving terminal are provided. To increase the number of data packets of which undamaged data can be derived under identical reception conditions in a backward-compatible way the present invention provides a subchannel structure comprising a predetermined number of data packets and a predetermined number of error control packets, wherein each of the error control packets comprises an error control code field the data of which is generated based on at least a part of the packet data field and/or at least a part of the packet header of the data packets and a CRC field preceding the error control code field for protecting same.

Provided are a method and apparatus for providing an Internet Protocol Datacasting (IPDC) service. The IPDC service providing apparatus includes a data input unit generating an IP packet and signaling information of the IP packet; a packet generation control unit determining a type of an Internet Protocol Data Group (IPDG) packet that is to be generated by encapsulating the IP packet, on the basis of characteristics of the IPDC service; an IPDG packet generation unit generating an IPDG packet according to a data type of the IP packet, and generating an IPDG packet for the signaling information of the IP packet; a transfer stream packet generation unit generating the IPDG packet as a transfer stream packet; and a transfer unit transmitting the transfer stream packet. Accordingly, it is possible to provide an IPDC service while efficiently using a bandwidth, in a Digital Audio Broadcasting (DAB) system.

A digital audio broadcast channel is used in accordance with the principles of the present invention to broadcast local content information signals included with an associated geographically identifying code (e.g., a zip code) for reception only by those receivers associated with the geographically identifying code. Preferably, local content broadcasts containing audible information are preferably compressed for transmission to increase the capacity of the channel. A disclosed receiver monitors received signals for active local broadcasting relating to that particular locality, and switches to the reception of that local content information signal instead of the normal mode of reception of a general broadcast information signal for the duration of the local content information signal. Preferably, the unique local broadcast identifier code is contained in a header of the transmitted data packets. General broadcast content information and local content information can be received substantially simultaneously such that the audio signals relating to the general broadcast content and the local content are superimposed on one another, or reception of the local information may preempt reception of general broadcast information.

The in-band adjacent-channel digital audio broadcasting system includes a scrambling unit for scrambling a signal to be broadcasted, thereby generating a scrambled signal; an outer coding unit for performing a first encoding of the scrambled signal, thereby generating an outer encoded signal; an outer interleaving unit for performing a first interleaving of the outer encoded signal a byte by byte basis, thereby generating an outer interleaved signal; an inner coding unit for performing a second encoding the outer interleaved signal, thereby generating an inner encoded signal; an inner interleaving unit for performing a second interleaving of the inner encoded signal, thereby generating an inner interleaved signal; a modulating unit for modulating the inner interleaved signal, thereby generating an orthogonal frequency division multiplexing (OFDM) symbols; a guard interval inserting unit for inserting a guard interval between the OFDM symbols in order to eliminate an inter-symbol interference, thereby generating an OFDM frame; and an RF processing unit for performing a conversion of the OFDM frame into an analog radio frequency signal so that the OFDM signal can be transmitted in a specific frequency channel of an FM frequency band, and for amplifying and outputting the analog radio frequency signal.

In a mobile communications device, a method of processing data received from digital audio broadcast receiver hardware to generate an electronic programme guide for the content provided by a plurality of sub-channels received by said receiver, the method comprising: i) processing each file containing electronic programme information for a plurality of programmes within a predetermined period of time to extract at least one relevant informational element relating to a characteristic of each of said plurality of individual programmes; ii) generating a data record for each individual programme, the data record having a structure which includes at least one said informational element as a searchable index enabling subsequent retrieval of said information; iii) storing each said data record received in a data store, wherein said data store is configured to be searchable using said one or more indices.

A method of provisioning a mobile communications device with a digital audio broadcast (DAB) application configured to run on the mobile communications device, the method comprising: generating a request for at least one component of the DAB application using a communications application of said mobile communications device; communicating the request over a bi-directional wireless communications network to a remote server; receiving the request at the remote server; processing the request to identify one or more DAB application components suitable for download to the mobile communications device; downloading said one or more DAB application components to the mobile communications device over said bi-directional wireless communications network; and installing said one or more DAB application components onto said mobile communications devices.

A DSP-enabled system and method for increasing intelligibility of audio on amplified telephones by providing digital audio processing customizable based on characteristics of hearing loss specific to individual end users are disclosed. The DSP-enabled amplified telephone generally comprises a DSP capable of implementing at least one digital processing mode for processing audio input, a volume control for allowing the user to select a volume control level, and a controller for interfacing between the DSP and the volume control. The DSP is optionally programmable to implement a processing mode selected from multiple processing modes that the DSP is capable of implementing. The mode is selected based upon the user's hearing loss characteristics. The DSP may be further customized by being programmed with frequency response, compression ratio, and/or knee point according to hearing loss characteristics of the user. The DSP may implement digital TILL, BILL, and/or PILL (treble, bass, and programmable increase at low levels, respectively), all of which apply more amplification to softer inputs than to louder inputs, as well as input compression, output compression, and/or finite impulse response (FIR) filter tone control.

A method and apparatus for transmitting a plurality of data streams in a wireless broadcast system are provided. The method includes mapping the plurality of data streams onto a super-frame that includes a plurality of frames; inserting signalling information in a first signalling information field for assisting in the reception of a first number of said plurality of data streams for a given frame, the first number being less than or equal to a limit applicable to each of the plurality of frames; dependent on a number of data streams for the given frame being greater than the limit, inserting signalling information in a second signalling information field; inserting said first and second signalling information fields in a preamble section of said given frame; and transmitting the plurality of frames.

A method is provided for transmitting a plurality of informational video programs over a single digital transport stream to a plurality of receivers, wherein the receivers are operative to select from the transport stream data identified with any given program and to decode the identified data into a displayable video signal. The method consists of storing a plurality of the informational video programs, scheduling them along corresponding simultaneous time lines, rendering each program and encoding, according to standards, into a video stream, multiplexing the video streams in an interleaved manner, and formatting them to become the transport stream, wherein any of the operations of scheduling, rendering encoding and multiplexing are such that images, obtained by decoding transmitted data identified with any of the programs and displaying the resultant video signal, are essentially similar to those obtainable by rendering and encoding the programs separately, transmitting the respective encoded program alone over a similar transmission stream, decoding the transmitted data and displaying the resultant video signal.

A method for receiving-transmitting ground mobile multimedia broadcast based on free charge DAB includes configuring parameter according multimedia service to carry out source and channel coding and embedding coded service data in master service channel MSC as well as carrying out channel coding to form T-MMB transmission frame being sent out at sending end, synchronizing and decoding received signal and picking up configured parameter as well as carrying out decoding on source and channel at receiving end.

A method, apparatus, and computer-readable media for determining the position of a user terminal comprises receiving, at the user terminal, a digital audio broadcast signal; and determining a pseudo-range between the user terminal and a transmitter of the digital audio broadcast signal based on a known component of the digital audio broadcast signal; wherein the position of the user terminal is determined based on the pseudo-range between the user terminal and the transmitter of the digital audio broadcast signal and a location of the transmitter of the digital audio broadcast signal.

A method for processing a composite digital audio broadcasting signal including an analog modulated portion in a central frequency band and digitally modulated portions in upper and lower sidebands with respect to the central frequency band, the method comprises the steps of wideband filtering the composite digital audio broadcasting signal to produce a first intermediate frequency signal, narrowband filtering the composite digital audio broadcasting signal to produce a second intermediate frequency signal, simultaneously processing the first intermediate frequency signal to retrieve a digitally modulated version of program material from the first intermediate frequency signal, and processing the second intermediate frequency signal to retrieve an analog modulated version of the program material from the second intermediate frequency signal, making a determination of the quality of the digitally modulated version of the program material, and using the quality determination to select the analog modulated version of the program material, the digitally modulated version of the program material, or a combination of the analog modulated version of the program material and the digitally modulated version of the program material as an output signal. Receivers that process a digital audio broadcasting signal using the method are also disclosed.

The invention is a digital television broadcasting system based on MPEG-1, the system is made up of network, digital television broadcasting system based on MPEG-1 through the network and digital television broadcasting receiving system based on MPEG-1. The transmitting system includes MPEG-1 coder, disturber, IP data flow complex device and modulator, the receiving system includes resonance device, demodulator, TS data flow demultiplexing device, and MPEG-1 decoder. The cost is low, and it can display program source with MPEG-1 format with IP mode.

In a digital broadband broadcast transmitter, digital data is time interleaved for transmission, and the time interleaved digital data is transmitted in a digital broadband broadcast transmission towards a plurality of receivers. A cellular transmitter is operated in an apparatus. In the same apparatus, the digital broadband broadcast transmission transmitted by the digital broadband broadcast transmitter is received, and the received digital broadband broadcast transmission is time deinterleaved.

The invention discloses a method for achieving digital televisions in accordance to DVB standards in an Andriod system. The method is characterized by comprising the following steps: using a socket mode to achieve digital television functions in a second layer of the Andriod system; and providing the digital television functions achieved in the second layer for application programs in a Java application layer through a Java application program interface (API) for calling, achieving digital television functions in a C framework layer by using the socket mode, and providing the digital television functions achieved in the C framework layer for application programs in the Java application layer through the Java API for calling. Accordingly, a large number of digital television related applications can call the Java API directly; the problem that how Java applications achieve digital television software module functions by using a base layer C language through the Java API is solved; and development efficiency and portability of the Java applications are greatly improved.

The invention provides methods for sending and receiving a digital audio signal in a digital audio broadcasting system. Service data are scrambled and subjected to low density parity check (LDPC) coding, constellation mapping and sub-carrier interleaving at a sending end; service description information is scrambled and subjected to convolutional coding, bit interleaving and constellation mapping; system information is subjected to convolutional coding, bit interleaving and constellation mapping; the information and discrete pilots are multiplexed together and mapped to a corresponding spectrum mode to form an orthogonal frequency division multiplexing (OFDM) frequency domain symbol; and conversion of a frequency domain and a time domain is performed, a logic layer frame structure is formed by connection, and a physical layer frame structure is mapped from the logic layer frame structure and framed for transmission. The invention has the advantages that according to the spectrum characteristics of the conventional frequency modulation (FM) frequency range, a flexible spectrum mode is designed, and the conventional analog FM broadcasting signal is not influenced. The invention is expandable in spectrum, flexible in system transmission parameter setting and applicable to single-frequency network and multi-frequency network modes.