Rohde and Schwarz Gmbh & Co. Kg

Norman Herzog

Jens Rusch-Ihwe

Michael John Simon

Michael Kramer

Günther Zurek-Terhardt

Guenther Zurek-Terhardt

A method for signaling a time and/or clock through a header station generating a transport datastream from video and/or audio data to at least one receiver of the transport datastream calculates the time information (PCR; RTP; T) integrated in a transport data packet of the transport datastream iteratively from the time information (PCR; RTP; T) of the transport data packet last transmitted in the transport datastream with integrated time information, from a transmission time of data bits transmitted since the last transmitted transport data packet with integrated time information in the transport datastream and from a clock (f; f). The time information (PCR, PCR; RTP, RTP; T, T) serves in each case for the signaling of times or a clock, and, in each case, contains a pulse number counted up to the transmission time of the respective transport data packet of the clock (f; f).

Method and a device for signalling transmission time and/or a system clock

A system for optimizing short-term stability of a clock source clock pulse synchronized with a long-term stable reference-clock transmits clock numbers of a first reference clock to the clock source, between an initialization time and several times within a data-packet network. The clock pulse is adjusted by controlling a difference between clock numbers of the first reference clock received in the clock source and clock numbers of the first reference clock between the initialization time and the reception times of the clock numbers of the first reference clock. Clock numbers of a second reference clock are transmitted to the clock source with the clock number of at least one second reference-clock source at individual times. The maximum difference between the first and the second reference clock is known. The difference between the clock pulse of the clock source and each second reference clock is limited to an adjustable threshold value.

Method and system for optimizing short term stability of a clock pulse

Mapping data packets of a first data stream into data fields of a second data stream at several transmitters is provided by generating a first data stream with first data packets containing data associated with stationary receivers and second data packets containing data associated with mobile receivers in a head-end, where second data packets at the start of a group of consecutively transmitted second data packets contain placeholders into which signaling information is filled. A first data stream is transmitted from the head-end to each transmitter. Each transmitter extracts signaling information from the second data packets indicating in which data slot and in which data sub-frame of a received data frame the second data packet is transferred. Each transmitter inserts synchronization data in a specific data packet in each data slot containing second data packets. The first and second data packets are mapped consecutively into the second data stream.

Method and system for synchronized mapping of data packets in an ATSC data stream

Time synchronization between a control center and transmitters in a single frequency network is provided by generating and receiving a first reference time signal with a high time and frequency accuracy in a short and long time horizon and a second reference time signal supplied to the control center with a low time and frequency accuracy in the short time horizon and a high time and frequency accuracy in the long time horizon. A transport data stream is generated and supplied to the transmitters with a time-variable data rate through the control center corresponding to a frequency of the second reference time signal. Time displacement of the transport data stream received from the control center is performed by a respective transmitter until the data packets of the transport data stream each containing a transmission time are transmitted at a correct transmission time.

Method and a system for time synchronisation between a control centre and several transmitters

Methods and devices are disclosed for generating a reorganized transport datastream from transport data packets of an original transport datastream displaces the first transport data packets contained in an original transport datastream into determined new positions within the reorganized transport datastream. The new positions are determined dependent upon a first data rate at which the first transport data packets of the reorganized transport datastream are stored in second buffers and a second data rate at which the first transport data packets of the reorganized transport datastream are read out from the second buffers.

Methods and devices for generating a reorganized transport datastream

A method and a device for transmitting a transport stream according to a digital television-transmission standard for stationary and/or mobile receivers with program and service data for a national and a regional broadcast determines the transmission capacity in the transport stream provided in each case for the national and the regional broadcast through a first multiplexer within a centrally positioned headend. The first multiplexer then fills the transport stream with program and service data for national broadcast within the transmission capacity of the transport stream provided for the broadcast and marks the transmission capacity provided within the transport stream for the regional broadcast. Second multiplexers provided in the regional headends and/or in the regional transmitters in each case fill the marked transmission capacity of the transport stream, transmitted in each case from the central headend to several regionally positioned headends and/or regionally positioned transmitters, with program and service data for regional broadcast.

Growing community of inventors

Berlin, Germany

Norman Herzog