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Despite the successful launch of Advanced Television Systems Committee (ATSC) 3.0 broadcasting worldwide, broadcasters are facing obstacles in constructing void‐less large‐scale single‐frequency networks (SFNs). The bottleneck is the absence of decent on‐channel repeater (OCR) solutions necessary for SFNs. In the real world, OCRs suffer from the maleficent feedback interference (FI) problem, which overwhelms the desired input signal. Moreover, the undesired multipaths between studio‐linked transmitters and the OCR deteriorate the forward signals' quality as well. These problems crucially restrict the feasibility of conventional OCR systems, arousing the strong need for cost‐worthy advanced OCR solutions. This paper presents an ATSC 3.0‐specific solution of advanced OCR that solves the FI problem and refines the input signal. To this end, the FI canceler and channel equalizer functionalities are carefully implemented into the OCR system. The presented OCR system is designed to be fully compliant with the ATSC 3.0 specifications and performs a fast and efficient signal processing by exploiting the specific frame structure. The real product of ATSC 3.0 OCR is fabricated as well, and its feasibility is verified via field and laboratory experiments. The implemented solution is installed at a commercial on‐air site and shown to provide substantial coverage gain in practice. [ABSTRACT FROM AUTHOR]

This paper presents technical requirements of on-channel repeaters (OCRs) to broadcast the terrestrial digital multimedia broadcasting (T-DMB) signals in single frequency network (SFN) environment. In order to meet such requirements, the configuration and implementation method of the equalization OCR are proposed. The proposed equalization OCR does not have only short processing delay, but also provides high quality transmitting signals with high power because of the rejection capability of a feedback signal introduced by incomplete antenna isolation and multipath signals existing between a main transmitter and the OCR. Computer simulations and laboratory tests results are provided to figure out performance of the proposed equalization OCR. Index Terms--Equalization, OCR, SFN, T-DMB.

A Single frequency network (SFN)design based on the Advanced Television Systems Committee (ATSC) terrestrial digital television (DTV) system normally causes interference among signals from multiple transmitters or repeaters in the network. The ATSC recommended practice (RP) A/111 introduces transmitter identification (TxID) signals embedded to the ATSC 8-VSB signals. A TxID signal analyzer is then used to detect the TxID signals and analyze the network. Following the analysis results, the SFN design can be managed by adjusting delay and power of multiple transmitters and repeaters. This paper presents basic concept of the Kasami sequence used as the TxID signals, and their insertion method to the ATSC 8-VSB signals. The structure of the TxID signal analyzer to efficiently detect TxID signals is proposed, and a theoretical approach to performance measurement of the TxID signal analyzer is discussed. In addition, computer simulation and laboratory test results are provided to evaluate the performance of the TxID signal analyzer. Index Terms--8-VSB, Analyzer, ATSC, DTV, SFN, TxID signal.

This paper presents novel modulation and pre-equalization methods to minimize a signal processing time delay in the Equalization Digital On-Channel Repeater (EDOCR) for the ATSC terrestrial digital TV system. The proposed modulation method uses Equi-Ripple (ER) filter for Vestigial Side Bands (VSB) pulse shaping instead of conventional Square Root Raised Cosine (SRRC) filter. And the proposed pre-equalization method calculates pre-equalizer filter coefficients by comparing a base-band signal as a reference signal and a demodulated repeater output signal, and then creates new VSB pulse shaping filter coefficients by the convolution of the ER filter and the pre-equalizer filter coefficients. The new VSB pulse shaping filter minimizes the time delay of EDOCR by adjusting the number of its pre-taps and also compensates the linear distortions due to the use of the ER filter and mask filter. Index Terms--ATSC, modulation, on-channel repeater, pre-equalization, SFN.

A novel pre-equalization method for terrestrial DTV transmitters is presented. A pre-equalizer is used in transmitters to correct group delay and amplitude distortions caused by a channel filter. In the proposed pre-equalizer, an equation-error adaptive IIR filtering scheme is adopted unlike the conventional pre-equalization using FIR filtering. The pole-zero modeling property of IIR filters improves the signal-to-noise ratio by compensating for various linear distortions existing in DTV transmitters as well as the channel filter distortion. Simulation results show that the proposed IIR pre-equalizer performs better than the FIR pre-equalizer in terms of the residual mean-square error. Index Terms--Channel filter, DTV, IIR, pre-equalizer, transmitter.

This paper presents a guideline for designing an Equalization Digital On-Channel Repeater (EDOCR) and proposes an efficient method to implement it. The major concerns in the design of an EDOCR are shortening the system delay, maintaining synchronization between a main transmitter and an EDOCR, obtaining high signal to noise ratio (SNR) output, and enabling operation in an environment of adjacent channel interference. The short system delay is achieved adopting a demodulation scheme without an additional lowpass filter to remove harmonics, an intelligent slicer of a trellis decoder with a trace back depth of 1 for equalization, and an equi-ripple filter for the 8-VSB pulse shaping filter. To maintain the synchronization, the frequency offset information extracted from the received signal is reflected on a re-transmitting signal. Distinguished features of the EDOCR are adaptive equalization with the intelligent slicer which corrects symbol errors caused by on-air interface including the signal loopback, and the signal processing scheme which demodulates the received signal to a baseband symbol and re-modulates the symbol. Hence, the EDOCR can produce an exact replica of the main transmitter's signal with high SNR although there may be adjacent channels and input signal is distorted by multipath and noise. Finally, the performance evaluation of the designed EDOCR in both simulation and laboratory tests are presented and implementations of single frequency networks employing EDOCRs are discussed. Index Terms--ATSC, digital TV, equalization, on-channel repeater, SFN.

This paper presents and analyses field test results of the Enhanced-VSB (E-VSB) system proposed by Zenith/ATI and adopted as an Advanced Television Standard Committee (ATSC) standard. The possibility of successful reception at outdoor and indoor test points according to types of antennas, noise margin, and ease of reception are measured to analyse performance improvement of the E-VSB system. Verification of backward compatibility between the E-VSB and conventional 8-VSB systems, selection of test points, and configurations of the transmitter and the test vehicle are also presented. The field test results show that the E-VSB system does not only outperform the 8-VSB system at severe multipath environment such as indoor reception, but also is fully backward compatible with it. Index Terms--ATSC, DTV, enhanced-VSB, field test, 8-VSB.

Digital On-Channel Repeater (DOCR) can be used for Single Frequency Networks (SFN's). It is much simple and low cost compared to Distributed Transmitter which needs Studio to Transmitter Link (STL). However, traditional DOCR has one of those defects such as a power limit, a long time system processing delay or a poor output signal quality. In order to overcome all of those defects, we introduce Equalization DOCR (EDOCR) which regenerates the original 8-VSB output signal with relatively short time system processing delay. Lab. and Field test results show that the EDOCR can eliminate the loop-back signal up to 5.5 dB with 5.5 [micro]s system processing delay. By using EDOCR, we can save spectrum resources and extend coverage areas. Index Terms--DOCR, equalization, SFN.

This paper analyzes the error propagation phenomenon in the decision feedback equalizer (DFE) for the receivers of Advanced Television Systems Committee (ATSC) digital television (DTV) and presents the performance upper-limits of the DFE by comparing various error propagation cases and the no-error propagation case. As one approach to the performance limit, we consider a blind DFE, adopting a trellis decoder with a trace-back depth of 1 as a decision device. Through simulation, we show how much the DFE performance in ATSC DTV receivers is affected by error propagation. We found that while blind equalization is preferable to decision-directed (DD) equalization at signal-to-noise ratio (SNR) values less than 18 dB, DD equalization is superior to blind equalization at SNR values greater than 18 dB. In addition, symbol error rate curves quantitatively show that the performance difference in the DFE caused by error propagation becomes clearer at the trellis decoder following the DFE. The analysis results presented in this paper will be very informative for developing equalization algorithms for ATSC DTV receivers. Index Terms--ATSC, blind equalization, DFE, DTV, error propagation.

This paper theoretically and empirically explores the reliability gain that can be obtained by installing multiple antennas in on‐vehicle broadcasting receivers. Analytical derivations reveal that maximal‐ratio‐combining‐based diversity allows a multi‐antenna receiver (MR) to achieve significantly better coverage probability than a single‐antenna receiver (SR). In particular, the notable MR gains for low‐power reception and high‐throughput services are highlighted. We also discuss various aspects of mobile MRs, including geometric coverage, volume of the users served, and impact of receiver velocity. To examine the feasibility of MRs in the real world, extensive field experiments were conducted, particularly with on‐air ATSC 3.0 broadcast transmissions. Relying on the celebrated erroneous second ratio criterion, MRs with two and four antennas were verified to achieve notable reliability gains over SRs in practice. Furthermore, our results also prove that layered‐division multiplexing can cope better with receiver mobility than traditional time‐division multiplexing when multiple services are intended in the same radio frequency channel. [ABSTRACT FROM AUTHOR]