What is the ATSC recommendation for the Signal-to-Noise-Ratio (SNR) for an 8-VSB digital signal?

The ATSC (Advanced Television Systems Committee) recommends a Signal-to-Noise-Ratio (SNR) of 27dB for an 8-VSB (8-level vestigial sideband) digital signal. This level of SNR is crucial for maintaining the integrity of the signal and ensuring that the digital transmissions are robust enough to be received clearly without errors. At this 27dB threshold, the system can effectively distinguish the signal from background noise, thereby facilitating a reliable reception and minimizing the chances of signal degradation.

Setting the SNR at 27dB is a balance between achieving good signal quality while also being achievable in most transmission scenarios. Lower SNR thresholds could result in a higher error rate in the data stream, whereas higher thresholds, while potentially yielding clearer signals, may not be necessary for typical broadcast scenarios and could require more power or advanced transmission technologies. This recommendation is grounded in practical considerations of real-world broadcasting environments, where the level of noise can vary significantly.