Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04B—TRANSMISSION
  • H04B7/00—Radio transmission systems, i.e. using radiation field
  • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
  • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
  • H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
  • H04B7/0802—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using antenna selection
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
  • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
  • H04N21/4302—Content synchronisation processes, e.g. decoder synchronisation
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
  • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
  • H04N21/433—Content storage operation, e.g. storage operation in response to a pause request, caching operations
  • H04N21/4331—Caching operations, e.g. of an advertisement for later insertion during playback
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
  • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
  • H04N21/438—Interfacing the downstream path of the transmission network originating from a server, e.g. retrieving encoded video stream packets from an IP network
  • H04N21/4383—Accessing a communication channel
  • H04N21/4384—Accessing a communication channel involving operations to reduce the access time, e.g. fast-tuning for reducing channel switching latency
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client 
  • H04N21/63—Control signaling related to video distribution between client, server and network components; Network processes for video distribution between server and clients or between remote clients, e.g. transmitting basic layer and enhancement layers over different transmission paths, setting up a peer-to-peer communication via Internet between remote STB's; Communication protocols; Addressing
  • H04N21/643—Communication protocols
  • H04N21/64315—DVB-H

Definitions

• the third application for the fast switching described here results when the receiver changes from the transmission area of one transmitter to the area of another transmitter.
• the control unit of the receiver recognizes that another transmitter meanwhile supplies the better signal (so-called transmitter tracking, for example known from DE 10 2005 039 507 A1) and switches over without interruption.
• transmitter tracking for example known from DE 10 2005 039 507 A1
• both transmitters typically provide the same picture quality. In the following, therefore, it is no longer spoken of high and low bit rate or quality, but of primary -the first selected and alternative receive path.
• Tuner and demodulator need to synchronize to the new reception path. It can be assumed that this has already happened during operation before the changeover and this time can be set to zero.
• T buffer The data buffers for the video and audio decoder must be filled.
• the video decoder decodes and displays the reference image. This time is typically less than the display time of an image (20ms at 50Hz and 16.7ms at 60Hz television systems).
• Video decoding is the part of a system on chip (IC) that needs the most computational power. Doubling this resource means significantly higher IC costs.
• the second video decoder memory For both the buffering and the decoded reference images. Of the Memory requirements are in the range of several 10 Mbytes. The bus bandwidth to the memory must also be increased significantly. It may be necessary to use a second memory module or a module with a wider data bus.
• a reception train comprises all the means from the reception (antenna) of the high-frequency signals to the output at which the If two or more receive trains, ie receive trains in parallel, are provided, all the units of a receive train are duplicated (with two parallel receive trains) or more than twice, for example, the one from an antenna received signals can be made available to a tuner and a downstream demodulator and converted by them from the received radio frequency into an intermediate frequency . These signals enable an analog-to-digital converter to generate a digital data stream (for example an MPEG-2 data stream).
• the D Atenstrom in video data, audio data and possibly other data splits.
• the video data is fed to a video decoder and the audio data is fed to an audio decoder, to the outputs of which further units can be connected before the signals (data) processed by the decoders are made available to a unit for reproduction, in particular for video and audio signals.
• a Empfangszug in particular with regard to the solution B) be understood in that depending on the number of receive trains while tuner, demodulator and demultiplexer and analog Digital converters are multiple, but are available from the demultiplexer of the respective Empfangszuges on only a single video decoder, on only a single audio decoder and optionally downstream further, but only once existing units.
• tuner, demodulator and demultiplexer and analog Digital converters are multiple, but are available from the demultiplexer of the respective Empfangszuges on only a single video decoder, on only a single audio decoder and optionally downstream further, but only once existing units.
• the effort required for this purpose with respect to the reception and signal processing means should be kept as low as possible.
• the data of the one Empfangszuges are stored by a ring buffer, while using the other Empfangszuges the data edited and made available for playback, wherein then, when switched from the other to the one receive train, the video decoder receives the data stored in the ring buffer for further processing.
• This method and its corresponding hardware implementation has the following advantages.
• two (or more than two) receive lines are provided on the input side of the video and audio decoder. This means that with the one Empfangszug the desired station (TV station) can be received and played, while with the other Empfangszug a station tracking can take place. If it turns out that the signals received by the one receiving train of the desired television station with the signals of the other receiving train can be better received, is switched from the previously used Empfangszug to the other Empfangszug. Since this switching process is established per se, but causes problems when starting the video decoder with the newly supplied data, it is provided according to the invention that the data of the Empfangszuges are stored in the ring buffer.
• the ring buffer can make these data available to the video decoder when it receives the data of the reception train, which until then has been receiving and processing the high-frequency signals in the background for the purpose of station tracking, ie has converted them into digital signals.
• This allows the video decoder to synchronize faster to the data signals provided to it by the switched receive train, thereby leaving the television picture largely stable to the viewer.
• a ring buffer is provided which can accommodate at least the amount of data between two reference pictures. This buffer is filled permanently and simultaneously with the primary path.
• the video decoder is fed with the data from the most recent reference image.
• the video decoder thus receives data from the "past" and can start decoding immediately, eliminating Tp U ff er + T Re f.
• the digital data stream is supplied to the demultiplexer in each Empfangszug, which in turn, as already described, divides the data stream into at least the video and audio signals.
• the video signal of each receiving train is supplied to a switching unit, so that the video signals provided by the two receiving trains can be supplied to the video decoder after the switching unit. Namely, either the video signal of the one Empfangszuges or the video signals of the other Empfangszuges the video decoder is supplied.
• the ring buffer is provided which stores those video signals which are output from the demultiplexer, which is not connected to the video decoder at this time.
• the video decoder receives the data stored in the ring buffer so that it can start working immediately. At the same time it is ensured that the ring buffer not only outputs the data to the video decoder, which has been assigned after the switching process of a Empfangszug, but that after the switching operation of the ring buffer of the now no longer connected to the video decoder receive train whose data are supplied so he can save this for the next switching process.
• the ring buffer can always be active in both paths (receive). In case the video decoder decays the data, the ring buffer will not be completely filled.
• the read pointer (controlled by the decoder) will closely follow the write pointer (controlled by the demultiplexer). If the decoder does not collect data (eg on the alternate path before switching or on the primary path after switching), the read pointer will not move from the decoder and the buffer will fill up. Once the write pointer has reached the read pointer, the read pointer must be advanced by the demultiplexer or other control entity. The write pointer must not "overtake" the read pointer. The buffer has now reached the maximum capacity. If the decoder is switched to a filled buffer, the ring buffer is emptied by the fast forward, because the data from the transmitter are slower than they are processed by the decoder in fast forward. The initial state is restored.

Landscapes

• Engineering & Computer Science (AREA)
• Signal Processing (AREA)
• Multimedia (AREA)
• Computer Networks & Wireless Communication (AREA)
• Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
• Circuits Of Receivers In General (AREA)
• Radio Transmission System (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

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Family Applications (1)

Country Status (7)

Cited By (2)

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• 2013
  • 2013-02-04 JP JP2014556018A patent/JP2015511458A/ja active Pending
  • 2013-02-04 WO PCT/EP2013/052141 patent/WO2013117514A1/de active Application Filing
  • 2013-02-04 CN CN201380007891.7A patent/CN104094609A/zh active Pending
  • 2013-02-04 EP EP13702231.5A patent/EP2813087A1/de not_active Ceased
  • 2013-02-04 DE DE102013201749A patent/DE102013201749A1/de active Pending
  • 2013-02-04 RU RU2014134927A patent/RU2014134927A/ru not_active Application Discontinuation
  • 2013-02-06 TW TW102104679A patent/TWI554111B/zh not_active IP Right Cessation

Non-Patent Citations (2)

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