FIELD

This application relates to technical advances necessarily rooted in computer technology and directed to digital television, and more particularly to Advanced Television Systems Committee (ATSC) 3.0.

BACKGROUND

The Advanced Television Systems Committee (ATSC) 3.0 suite of standards is a set of over a dozen industry technical standards as indicated in ATSC A/300 for delivering the next generation of broadcast television. ATSC 3.0 supports delivery of a wide range of television services including, but not limited to, televised video, interactive services, non-real time delivery of data, and tailored advertising to a large number of receiving devices, from ultra-high-definition televisions to wireless telephones. ATSC 3.0 also orchestrates coordination between broadcast content (referred to as “over the air”) and related broadband delivered content and services (referred to as “over the top”). ATSC 3.0 is designed to be flexible so that as technology evolves, advances can be readily incorporated without requiring a complete overhaul of any related technical standard. Present principles are directed to such advances as divulged below.

SUMMARY

As understood herein, reception by a mobile receiver of ATSC 3.0 signals can be impaired by loss or attenuation of signal due to overpasses, tunnels, mountains, and tall buildings. Loss of signal could be many minutes long. Furthermore, while ATSC 3.0 provides error-correction as part of the modulation scheme to overcome many perceived impairments to the signal if the signal is lost for more than a second or two there can be a complete loss of image.

As further recognized herein, memory and processing power is becoming cheaper every day. Accordingly, present principles exploit an infrastructure that allows a receiving device, e.g., a mobile TV, to request packets from the broadcaster to replace missing or damaged packets in a large (10-15 minutes) buffer of the receiver. The replacement packets may be received from a back channel such as a cellular phone system such as 5G or 4G, or the back channel may be Wi-Fi when available.

To address channel change latency owing to use of a large buffer, multiple channels in the same multiplex as the currently tuned-to channel may be buffered for immediate tuning responsive to a channel change. Or multiple channels in a different multiplex (received through a secondary tuner) can be buffered. Multiple antennas may be employed to permit tuning to and buffering multiple different signals (instead of the same exact signal) to perform a rapid channel change function that is error-free.

Accordingly, a digital television (TV) system includes at least one mobile receiver that in turn includes at least one processor programmed with instructions to receive a first digital TV broadcast stream. The instructions are executable to store, in at least one buffer, at least one period of the first stream prior to presenting the first stream. Furthermore, the instructions are executable to identify at least one packet discrepancy in the first stream, and to request, from at least one back channel source, data to cure the packet discrepancy. The instructions are executable to receive the data from the back-channel source, insert the data into the buffer to cure the packet discrepancy, and play the first stream from the buffer.

In example embodiments the back-channel source includes at least one wireless telephony network and/or at least one Wi-Fi source.

In some embodiments the packet discrepancy includes a missing packet and/or a damaged packet.

In non-limiting examples the instructions may be executable to, simultaneously with buffering the first stream, buffer at least a second stream. The second stream may be received in a multiplex containing the first stream, or the first stream may be received at a first tuner of the mobile receiver and the second stream may be received at a second tuner of the mobile receiver.

In some examples the instructions can executable to receive a channel change command to present a new channel. In these examples the instructions can be executable to, responsive to the channel change command, determine whether packets associated with the new channel are in the buffer, and responsive to determining that packets associated with the new channel are in the buffer, immediately access the packets associated with the new channel from the buffer and present the new channel. The instructions may be executable to, responsive to determining that packets associated with the new channel are not in the buffer, begin to buffer, for a second period shorter than the first period, packets of the new channel. The instructions can be executable to present the new channel.

Further, in these last examples the instructions can be executable to determine whether to add the new channel to a set of streams to be buffered for the first period, and responsive to identifying that the new channel should be added to the set of streams to be buffered for the first period, add the new channel to the set.

In non-limiting embodiments the instructions are executable to identify at least one outage period associated with at least one route. The outage period can be a period during which broadcast digital TV is not receivable. The instructions may be executable to establish the first period based at least in part on the outage period.

In non-limiting embodiments the instructions may be executable to receive a command to stop presenting digital TV on the mobile receiver. Responsive to the command to stop presenting, the instructions can be executed to continue to buffer at least one digital TV stream in the buffer. The instructions may be executable to, responsive to a command to commence playing digital TV on the mobile receiver, identify whether packets associated with a stream to be played are in the buffer, and responsive to determining that packets associated with the stream to be played are not in the buffer, begin to buffer, for a second period shorter than the first period, packets of the stream to be played. The instructions can be further executable to play the stream to be played from the buffer, create a duplicate buffer of the stream to be played with a period longer than the second period, and selectively switch to playing packets in the duplicate buffer.

In another aspect, an assembly includes at least one mobile receiver of digital television, at least one digital television over-the-air (OTA) source of wireless digital TV signals receivable from the OTA source by the mobile receiver, and at least one back channel source of wireless digital TV replacement content receivable from the back-channel source by the mobile receiver. The back-channel source includes at least one wireless telephony network or at least one Wi-Fi source or both a wireless telephony network and a Wi-Fi source.

In another aspect, a method includes broadcasting digital TV signals to at least one mobile receiver and sending replacement packets for defective or lost packets in the digital TV signals to the mobile receiver from a cellular telephony network or a Wi-Fi source.

The details of the present application, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which:

