Abstract: A data storage element comprising a substrate and a data track disposed on the substrate, the data track comprising a plurality of data sectors, each of the data sectors being formatted in accordance with a first digital data standard and comprised of a control data portion and a payload data portion, each of the payload portions including a plurality of data packets formatted in accordance with a digital television standard. In particular, the data packs correspond to program stream packs specified in the DVD standard and the data packets correspond to transport packets specified in the ATSC standard. The present storage element enables the data stored thereon to be read by a conventional DVD front end and provided to an ATSC receiver without processing the contents of the transport packets. Therefore, the present invention allows ATSC data to be stored on a DVD disc and to be provided in a manner that can fully realize the display capabilities of the ATSC receiver.

Abstract: A hierarchical QAM system allows the transmission of different sources by embedding the relative constellation points. A QAM transmitting system, includes a source of a level 1 and a level 2 data stream, each data stream carrying successive symbols. A hierarchical QAM transmitter, coupled to the level 1 and level 2 data stream source, generates a hierarchical QAM signal in which a level 1 symbol is represented by a data point in one of four quadrants in the I-Q plane, and a level 2 symbol is represented by the data point in one of four sub-quadrants surrounding a center point of the quadrant containing the level 1 data point. The level 2 data point is spaced away from the center point by a grouping factor set to more closely match the bit error rate performance of the level 1 and level 2 data streams.

Abstract: A OAM receiver includes a source of a received hierarchical OAM signal. The hierarchical OAM signal represents successive data points in the I-Q plane, each data point being in one of four quadrants. Circuitry, coupled to the hierarchical OAM signal source, calculates the location in the I-Q plane of the center-of-gravity of successive received data points in a quadrant. A level 1 decoder is responsive to a received data point and detects the quadrant in the I-Q plane of a received data point. Further circuitry, coupled to the hierarchical OAM signal source and responsive to the calculating circuitry, translates the received data point in the I-Q plane such that the center-of-gravity of the detected quadrant is translated to the origin of the I-Q plane. A level 2 decoder is then responsive to the translated data point for detecting the quadrant of the translated data point.

Abstract: A hierarchical QAM system allows the transmission of different sources by embedding the relative constellation points. At the transmitter the constellations generated by the different sources are remapped by a grey coder and then combined. At the receiver, the different source data are decoded by using a corresponding grey code demapper.

Abstract: The power of the respective codes used by the first and second error detection/correction circuitry are such that the coded bit error rate of the first data stream is more closely matched to the coded bit error rate of the second data stream. A hierarchical QAM system allows the transmission of different sources by embedding the relative constellation points. The hierarchical QAM transmitter encodes the first data stream using a code having a first detection/correction power and encodes the second data stream using a code having a second detection/correction power.

Abstract: A Conversion system merges and converts data in a plurality of different data formats from a plurality of different sources, to a selected output data format for transmission on a selected transmission channel. A method for digital data format conversion involves de-packetizing an input packetized datastream. A timing recovery parameter is formed in response to a desired output data format. The depacketized data is re-packetized in response to the desired output data format and the timing recovery parameter is incorporated in the re-packetized data. The re-packetized data is multiplexed in response to the selected format and provided to an output channel.