Abstract: Digital television (DTV) broadcasting using COFDM modulation is designed to modulate orthogonal frequency-division-multiplexed (OFDM) mid-band carriers with metadata including synchronization signals and transmission-mode signals. DTV signals modulate OFDM carriers occupying portions of the frequency spectrum of the transmission channel that extend in frequency both below and above these mid-band carriers. The OFDM midband carriers are capable of signaling when a new broadcast service is used that differs from the one disclosed. The signaling is provided by modulating the midband carriers with respective elements of signature sequences, each of which signature sequences is composed of Zadoff-Chu sequences and repetitive pseudo-random sequences scrambled by a Zadoff-Chu sequence.

Abstract: Turbo-coded data are transmitted using quadrature amplitude modulation (QAM) of COFDM carrier waves in digital television (DTV) broadcast systems. The QAM symbol constellations map the parity bits of the turbo coded data so as to be de-mapped with higher confidence levels than the data bits, facilitating turbo decoding. A preferred DTV receiver delays the first transmissions of time-slices of a service selected for iterative-diversity reception to concur with second transmissions of those time-slices. The complex coordinates of QAM constellations in the delayed first transmission and the second transmission of the same time-slice are combined by a maximal-ratio QAM combiner after COFDM demodulation, but before de-mapping QAM constellations and turbo decoding. In a less-preferred DTV receiver, QAM constellations in the delayed first transmission of each time-slice and in the second transmission of the same time-slice are de-mapped separately.

Abstract: Transmitter apparatus to broadcast coded orthogonal frequency-division multiplexed (COFDM) radio-frequency carriers conveying low-density parity-check (LPDC) coding transmits the same coded DTV signals twice some time apart. The coded DTV signals of initial transmissions and of final transmissions are mapped to quadrature amplitude modulation (QAM) of the COFDM carriers according to first and second patterns, respectively. Bits that map to lattice points in the first mapping pattern more likely to experience error are mapped to lattice points in the second mapping pattern less likely to experience error. Bits that map to lattice points in the second mapping pattern more likely to experience error are mapped to lattice points in the first mapping pattern less likely to experience error. Receiver apparatus combines the earlier and later transmissions of twice-transmitted COFDM signals as part of iterative procedures for de-mapping QAM and decoding the LDPC coding of the DTV signals.

Abstract: Transmitter apparatus to broadcast coded orthogonal frequency-division multiplexed (COFDM) radio-frequency carriers conveying low-density parity-check (LPDC) coding transmits the same coded DTV signals twice some time apart. The coded DTV signals of initial transmissions and of final transmissions are mapped to quadrature amplitude modulation (QAM) of the COFDM carriers according to first and second patterns, respectively. Bits that map to lattice points in the first mapping pattern more likely to experience error are mapped to lattice points in the second mapping pattern less likely to experience error. Bits that map to lattice points in the second mapping pattern more likely to experience error are mapped to lattice points in the first mapping pattern less likely to experience error. Receiver apparatus combines the earlier and later transmissions of twice-transmitted COFDM signals as part of iterative procedures for de-mapping QAM and decoding the LDPC coding of the DTV signals.

Abstract: Receivers with capability for iterative-diversity reception of COFDM digital television transmissions of repeated similarly coded data are described. Also described are receivers with capabilities for receiving COFDM digital television transmissions in which earlier transmissions of coded data are later followed by subsequent transmissions of the same data differently coded. The receivers use maximal-ratio code combining techniques for repeated components in the COFDM digital television transmissions. The receivers use turbo decoding techniques for concatenated coding of data in the COFDM digital television transmissions.

Abstract: In a DTV transmitter the bits of shortened BCH codewords that exhibit undesirably low densities of ONEs are ONEs' complemented before being further coded, and used to modulate carrier waves. In a DTV receiver the further coding is decoded after demodulation. The results of such decoding are processed to recover successive shortened BCH codewords, some of which are in TRUE form and others of which have had their bits ONEs' complemented. Each shortened BCH codeword is extended to full length with ZEROs, and decoding is attempted. Successful decoding confirms that the shortened BCH codeword was received in TRUE form. If decoding is unsuccessful, the bits of the shortened BCH codeword as received are ONEs' complemented, extended to full length with ZEROs, and decoding is attempted. Successful decoding confirms that the shortened BCH codeword was received in ONEs' complemented form and has subsequently been converted to TRUE form.

Abstract: Transmitter apparatus to broadcast coded orthogonal frequency-division multiplexed (COFDM) radio-frequency carriers conveying digital television (DTV) signals encoded using Bose-Chaudhuri-Hocquenghem (BCH) coding concatenated with subsequent low-density parity-check coding (LPDC) transmits the same coded DTV signals twice some time apart. The coded DTV signals are mapped to quadrature amplitude modulation (QAM) of the COFDM carriers. Preferably, the circular Fourier transforms of COFDM symbols in the earlier transmissions are rotated one half revolution respective to the circular Fourier transforms of corresponding COFDM symbols in the later transmissions. Receiver apparatus combines the earlier and later transmissions of twice-transmitted COFDM signals as part of iterative procedures for de-mapping QAM and decoding the concatenated BCH-LDPC coding of the DTV signals.

Abstract: Receivers for recovering ancillary data from parallel concatenated convolutional coding. (PCCC) imbedded in digital television (DTV) signals can utilize the non-systematic (207, 187) Reed-Solomon (RS) codewords included in the DTV signals to facilitate DTV receivers already in the field to continue being able to receive main-service transmissions. Such a receiver attempts to decode each non-systematic (207, 187) RS codeword in a time slot selected for reception. If such RS decoding is successful, indication of such success is used to verify the correctness of bits of the ancillary data or correct them when turbo decoding the PCCC encoding ancillary data in the time slot selected for reception. The updating of ancillary data bits during cycles of turbo decoding updates the non-systematic (207, 187) RS codewords in the time slot selected for reception, increasing the likelihood of RS decoding of those RS codewords being successful during subsequent cycles of turbo decoding.

Abstract: In a DTV transmitter the bits of shortened BCH codewords that exhibit undesirably low densities of ONEs are ONEs' complemented before being further coded, and used to modulate carrier waves. In a DTV receiver the further coding is decoded after demodulation. The results of such decoding are processed to recover successive shortened BCH codewords, some of which are in TRUE form and others of which have had their bits ONEs' complemented. Each shortened BCH codeword is extended to full length with ZEROs, and decoding is attempted. Successful decoding confirms that the shortened BCH codeword was received in TRUE form. If decoding is unsuccessful, the bits of the shortened BCH codeword as received are ONEs' complemented, extended to full length with ZEROs, and decoding is attempted. Successful decoding confirms that the shortened BCH codeword was received in ONEs' complemented form and has subsequently been converted to TRUE form.

Abstract: Transmitter apparatus to broadcast coded orthogonal frequency-division multiplexed (COFDM) radio-frequency carriers conveying digital television (DTV) signals encoded using Bose-Chaudhuri-Hocquenghem (BCH) coding concatenated with subsequent low-density parity-check coding (LPDC) transmits the same coded DTV signals twice some time apart. The coded DTV signals are mapped to quadrature amplitude modulation (QAM) of the COFDM carriers. Preferably, the circular Fourier transforms of COFDM symbols in the earlier transmissions are rotated one half revolution respective to the circular Fourier transforms of corresponding COFDM symbols in the later transmissions. Receiver apparatus combines the earlier and later transmissions of twice-transmitted COFDM signals as part of iterative procedures for de-mapping QAM and decoding the concatenated BCH-LDPC coding of the DTV signals.

Abstract: A digital television (DTV) system uses parallel concatenated coding (PCC), together with QAM constellations for modulating OFDM carriers. A first encoder responds to ONEs' complemented bits of randomized data to generate a first component of PCC. A second encoder responds to delayed bits of the randomized data to generate a second component of PCC. A constellation mapper generates QAM symbols responsive to successive time-slices of the first component of the PCC interleaved with successive time-slices of the second component of the PCC. An OFDM modulator generates a COFDM modulating signal responsive to the QAM symbols. In a receiver for the DTV system, the second component of the PCC and delayed first component of the PCC are iteratively decoded. Soft bits from the second component and delayed first component of the parallel concatenated coding are code-combined to supply soft randomized data used in that iterative decoding.

Abstract: Turbo-coded data are transmitted using quadrature amplitude modulation (QAM) of COFDM carrier waves in digital television (DTV) broadcast systems. The QAM symbol constellations map the parity bits of the turbo coded data so as to be de-mapped with higher confidence levels than the data bits, facilitating turbo decoding. A preferred DTV receiver delays the first transmissions of time-slices of a service selected for iterative-diversity reception to concur with second transmissions of those time-slices. The complex coordinates of QAM constellations in the delayed first transmission and the second transmission of the same time-slice are combined by a maximal-ratio QAM combiner after COFDM demodulation, but before de-mapping QAM constellations and turbo decoding. In a less-preferred DTV receiver, QAM constellations in the delayed first transmission of each time-slice and in the second transmission of the same time-slice are de-mapped separately.

Abstract: A portable, modular, and dynamically sized and shaped, above-ground, industrial-liquid-containment system is disclosed. In an exemplary embodiment, the system includes a plurality of elongated curbs, each of which has a substantially inverted-V-shaped cross-section. In variations, each curb can have a flat top surface, from which two walls extend downwardly at a predetermined angle. At the bottom of each of the curb walls, is a foot surface extending substantially parallel to the ground and to the flat top surface. The plurality of curbs are detachably coupled together to define a perimeter for a liquid-containment area. The height of the curbed boundary can be increased by installing curb-height extender members onto the first-layer of curb members. The defined containment-area floor and the plurality of curbs is continuously covered by liquid-impermeable sheeting in order to prevent leakage into the outer-ground environment.

Abstract: Methods for discontinuing interference-filter pre-coding of 8-VSB digital television (DTV) signals during ancillary-service transmissions are disclosed that do not disrupt reception of main-service DTV signals by receivers already in use. Receivers are disclosed for receiving ancillary-service transmissions without interference-filter pre-coding, which receivers include adaptive channel-equalization filters and subsequent decoders for CCC. The subsequent decoders for CCC respond to data slicing of adaptive channel-equalization filter responses that avoid the reduction of signal-to-noise ratio (SNR) caused by post-comb filtering. Certain of these M/H receivers employ selective post-comb-filtering to flatten the frequency spectrum of main-service components of received 8-VSB DTV signals, while leaving the frequency spectrum of M/H-service components of received 8-VSB DTV signals as received. This is done to generate signal from which filter coefficients for the channel-equalization filters are determined.

Abstract: Digital television broadcasting signals employ parallel concatenated convolutional coding, commonly called “turbo coding”, to improve reception by receivers in motor vehicles. Turbo coded Reed-Solomon codewords are transversally disposed in the payload fields of encapsulating MPEG-2-compliant packets to improve the capability of the Reed-Solomon coding to overcome deep fades. Turbo codewords are transmitted more than once in so-called “staggercasting”. Reception of DTV signals is improved by combining soft decisions concerning repeated transmissions of turbo codewords before turbo decoding. Only the data components of turbo codewords are transmitted twice in “punctured” staggercasting of turbo codewords, with parity components being transmitted only once, so code rate is reduced by a smaller factor than two.

Abstract: What is disclosed is a portable, modular, and dynamically sized and shaped, above-ground, industrial liquid-containment system. Typically, the system has an outer-containment perimeter and an inner-containment perimeter (a reservoir), thus providing two barriers for environmental protection. A reservoir is comprised of a plurality of substantially A-framed segments that are hinged at the top and allows for folding together when the center and bottom braces are removed. A key feature for the A-frame segments is in their lack of steel cladding on the water side of most A-frames segments. Instead, fabric and/or cargo netting is used because it reduces weight and grips the A-frame purlins as the weight of contained liquids exert stabilizing downward force on A-frames. In addition, a steel grid system can run along the reservoir floor to compensate for expansion forces due to both temperature and water-weight.

Abstract: A portable, modular, and dynamically sized and shaped, above-ground, industrial-liquid-containment system is disclosed. In an exemplary embodiment, the system includes a plurality of elongated curbs, each of which has a substantially inverted-V-shaped cross-section. In variations, each curb can have a flat top surface, from which two walls extend downwardly at a predetermined angle. At the bottom of each of the curb walls, is a foot surface extending substantially parallel to the ground and to the flat top surface. The plurality of curbs are detachably coupled together to define a perimeter for a liquid-containment area. The height of the curbed boundary can be increased by installing curb-height extender members onto the first-layer of curb members. The defined containment-area floor and the plurality of curbs is continuously covered by liquid-impermeable sheeting in order to prevent leakage into the outer-ground environment.

Abstract: At least two turbo decoding apparatuses are used in a receiver for concatenated convolutional coding transmissions imbedded in 8-VSB digital television signals. This permits turbo decoding procedures for the M/H Groups in any Parade consisting of eight or fewer M/H Groups to be interleaved so at least one M/H Slot interval after each of those M/H Groups has been received is available for decoding that M/H Group.

Abstract: Modified systems for broadcasting M/H data employ two-dimensional coding of RS Frames that combines transverse RS coding with subsequent byte-error-locating block coding that generates codewords of a prescribed standard length. This prescribed standard length is chosen such that an integral number of codewords of the byte-error-locating block code fits exactly, or substantially so, into the portion of each RS Frame that is encoded in CCC for inclusion within an M/H Group. The byte-error-locating block coding is CRC coding by way of one specific example or is Reed-Solomon (LRS) forward-error-correction (FEC) coding by way of another specific example. M/H receivers are described in which codewords of this byte-error-locating block coding are decoded and used to influence the soft decisions concerning data bits. Then, these soft decisions are processed and used for locating byte errors for the transverse Reed-Solomon (TRS) codes on an individual basis.

Abstract: Non-systematic (207, 187) Reed-Solomon codewords contain valuable information concerning the correctness of the outer convolutional coding of the serial concatenated convolutional coding (SCCC) used for transmitting digital television (DTV) data to mobile/handheld (M/H) receivers. M/H receivers are described that, before and during turbo decoding of the SCCC, decode (207, 187) Reed-Solomon (RS) coding of transport-stream packets encapsulating M/H DTV data. The results of the decoding the RS coding locate bytes in the outer convolutional coding of the SCCC very unlikely to be in error. The confidence levels of bits in those bytes are adjusted accordingly, so turbo decoding of the SCCC converges faster. In M/H receivers of preferred design, the results of decoding RS coded transport-stream packets are used to signal when such convergence is reached, to stop the iterative SCCC decoding procedures before a prescribed maximum number of iterations, thus to conserve operating power.