Wayne E. Bretl

VSB modulation used for terrestrial and cable broadcasts

A new vestigial sideband (VSB) digital transmission system has been developed for terrestrial and cable television broadcasting, and is currently being evaluated by the FCCs Advisory Committee on Advanced Television Service (ACATS) for adoption as the US standard. Initially, this new system must co-exist with the current analog NTSC television system. An important issue is the ruggedness and reliability of the RF data signal in real world environments. Receiver synchronization and signal processing play a vital role in reliable data decoding. >

VSB modem subsystem design for Grand Alliance digital television receivers

The functions of the vestigial sideband modem for the Grand Alliance digital TV are described. The partitioning of these functions is discussed in terms of the prototype hardware and possible future development. The VSB modem subsystem (tuner/demodulator) includes the functions of RF selection, local oscillator, and conversion; IF amplification and band shaping; baseband demodulation; AGC; co-channel filtering; synchronization and phase tracking of the carrier, the bit clock, and the data framing; equalization (ghost cancellation); forward error correction (trellis and RS codes); and data de-interleaving. The interaction and partitioning of these functions is discussed. >

Enhanced 8-VSB transmission for North-American HDTV terrestrial broadcast

We present a new robust backward compatible 8-VSB transmission system for HDTV terrestrial broadcast. The new transmission system allows better reception of signals for portable, mobile and indoor receivers. In the proposed system a scalable fraction of the main service is used to transmit robustly encoded data. The robust service has at least a 6 dB fade margin advantage over the main service. In addition, the data allocated to the robust stream can also be used at the receiver to improve the reception of the normal stream. The robust data is utilized by the normal stream receiver as randomly distributed training symbols which can be used in the equalizer to improve the receiver performance for dynamic multipath channels.

E-VSB-an 8T-VSB compatible system with improved white noise and multipath performance

Enhanced VSB (E-VSB) is a flexible, compatible outer coding enhancement to ATSC 8-VSB which trades payload bit rate for improved white noise and multipath performance when properly equipped receivers are utilized. It is transparent to legacy ATSC receivers. The coding method and experimental results are described.

Joint encoding/decoding enhanced multi-streams vestigial side band transmission (E-VSB) for North-American single carrier HDTV terrestrial broadcast

A new enhanced VSB (E-VSB) transmission system has been proposed to improve the North-American HDTV terrestrial broadcast. The system allows better reception for portable, mobile, and indoor receivers, by means of two backward compatible robust and scalable data stream, so-called 1/2 rate and 1/4 rate, that can co-exist with the normal stream. One originality of the system lies in the possibility for the receiver to enhance the normal transmission mode by combining the information provided by the two robust streams to improve cancellation of channel multipath. The improvement of the main service depends on the coding mechanism used for the enhanced streams and the number and the position of the enhanced symbols in the VSB frame. We illustrate the coding and the normal/enhanced packet multiplexing mechanisms that are used to achieve this goal.

Video encoding in the spectrum-compatible HDTV system

Video compression is achieved in the spectrum-compatible high-definition television (SC-HDTV) system by adaptive transform subband coding. The number of subbands is significantly increased, and the temporal processing is greatly reduced. Coefficients are transmitted as analog data; side information representing adaptation is transmitted as part of the digital data signal. >