A patent about how a TV finds a signal now targets the ATSC 3.0 standard
In July 2026, Cerinet USA Inc. filed twelve parallel infringement suits asserting U.S. Patent No. 9,253,428 B2 against thirteen defendants across the ATSC 3.0 (NextGen TV) supply chain. The patent describes how a receiver tuning into an unknown signal can identify its frame structure and transmission mode before decoding any payload. The complaints target the standard itself, not any one company's product line. Twelve cases identified, each with a jury demand and pleaded under 35 U.S.C. § 271. Case numbers and patent details as compiled in the Scintillation analysis. Claim text and the complaints were not reviewed for this article.
Twelve complaints, one patent, one standard
Each of the twelve complaints asserts the '428 patent and pleads infringement under 35 U.S.C. § 271. Thirteen defendants are named, because Kokusai Denki Electric America Inc and Kokusai Denki Electric Inc are named together. The defendants span consumer-device makers, tuner and receiver suppliers, and broadcast transmission-equipment providers.
| Defendant |
|---|
| Rohde & Schwarz GmbH & Co KG |
| SiliconDust USA Inc |
| LG Electronics Inc |
| Enensys TeamCast Inc |
| Kokusai Denki Electric America Inc and Kokusai Denki Electric Inc (named together) |
| Anywave Communication Technologies Co Ltd |
| Atlanta DTH Inc |
| Samsung Electronics Co Ltd |
| Sony Corp |
| Channel Master LLC |
| Hisense Group Co Ltd |
| Gates Air Inc |
| Case numbers, as listed in the analysis | ||
|---|---|---|
| 1:26-cv-00796 | 1:26-cv-00794 | 4:26-cv-00780 |
| 1:26-cv-00791 | 1:26-cv-00793 | 1:26-cv-07789 |
| 1:26-cv-03723 | 4:26-cv-00781 | 1:26-cv-00797 |
| 1:26-cv-00792 | 1:26-cv-03719 | 1:26-cv-00795 |
The analysis does not pair case numbers with defendants, and the filing venue for several of the cases was still to be confirmed. Two of the twelve carry a 4:26 prefix and the rest a 1:26 prefix. This page does not infer courts from the numbers.
Two named defendants, Samsung and Sony, also hold related broadcast-signaling patents in the reviewed set, which may bear on licensing and cross-licensing positions.
Blind tuning: identifying a broadcast before decoding it
A receiver landing on a channel knows nothing about what is being transmitted. Before it can demodulate any payload, it has to resolve the frame structure, the transmission mode and whether the signal belongs to a standard it supports at all. Carrying digital television over OFDM carriers was already a solved problem. The unsolved problem was discovery: identifying the signal quickly and reliably from a cold start.
Two reference designs existed, and neither fit broadcast television. DVB-T2 announces itself in-band, through a P1 preamble and Layer-1 (L1) pre- and post-signaling built into every frame, which sets FFT size, guard interval and physical-layer-pipe configuration. That works, but every new mode or future extension has to fit into an L1 signaling budget that was already tight. LTE took the opposite route. Its E-UTRA downlink modulates 72 central OFDM carriers with Zadoff-Chu-based synchronization signals and a Master Information Block, so a phone can discover network parameters at power-up regardless of channel bandwidth.
The invention carries the LTE discovery architecture into broadcast television at reduced scale. It dedicates 64 mid-band COFDM carriers to a metadata channel that runs in parallel with the payload carriers, not inside them. Those carriers are modulated with a two-part signature sequence. A Zadoff-Chu sequence identifies the general broadcast-system type, and a pseudo-random sequence scrambled by that same Zadoff-Chu sequence carries the finer-grained mode information.
The significance lies in the architecture, not in a new signal-processing primitive.
Cellular-style, bandwidth-agnostic system discovery is relocated into a dedicated broadcast metadata channel. A receiver can then tell what kind of signal it is looking at, and whether it can receive it, without enlarging the payload-frame signaling that DVB-T2-style standards already carry.
Discovery before decoding: the toolkits and the gap
More than one approach was pursued to solve the same underlying problem. The document set shows three branches.
| Branch | Who, and what they claim |
|---|---|
| Inside the frame | LG Electronics claims a bootstrap prefixed to the signal frame whose symbols describe the structure of the following preamble, with the preamble carrying the L1 signaling. Sony and Saturn Licensing claim the receiver side: detecting the bootstrap symbols, recovering synchronization timing, identifying which signature sequence was used and estimating frequency offset by cross-correlation. Samsung claims splitting additional information across preamble symbols and data symbols, so the preamble serves both signaling and additional channels. |
| Alongside the payload | Cerinet claims baseband metadata modulated onto mid-band OFDM carriers using Zadoff-Chu and scrambled pseudo-random sequences, with the receiver reading the Zadoff-Chu sequence to determine which standard governs the transmission. Allison and Limberg claim signature modulation of continual pilot carriers, with Barker coding near the end of each frame marking the start of the next, so the receiver detects the transmission mode from the pilots. |
| In a descriptor | Two Japanese documents held by Saturn Licensing carry the descriptive information in a network-information-table descriptor, not in the frame or its pilots. The descriptor identifies the segment format (one-, three- or 13-segment) of each jointly transmitted channel and the modulation scheme of each hierarchical tier. |
Adjacent work addressed other pieces. MIMO designs from NHK (inter-polarization interleaving across transmit antennas) and I/Q interleaving with constellation rotation from Sony addressed how robustly symbols, signaling symbols included, are delivered, but not how a receiver identifies the frame. Coherent Logix (a broadcast base station that pauses on a schedule so cellular base stations can use the band), Qualcomm (roadside-unit broadcasts carrying information for tuning to an MBMS broadcast) and Ericsson (listen-before-talk methods chosen by type of information) addressed coexistence between broadcast, cellular and unlicensed operation. Mitsubishi Electric (neighboring cells running different radio formats) and Ocado (adjustable low- and high-bandwidth links) addressed how differently configured transmissions share a system.
The result was a race toward the same opportunity. Separate organizations had established, piece by piece, that a frame can announce itself through a bootstrap, describe itself through preamble L1 data, identify its mode through pilot or mid-band metadata, and coexist with cellular traffic. The asserted patent stakes out the mid-band-metadata branch.
From reception to self-describing frames
The route to a broadcast-specific discovery channel was a convergence of separately maturing techniques, not a single-step invention.
Broadcast standards work had already established robust in-band preamble signaling. DVB-T2's P1 symbol and L1-pre and L1-post fields let a receiver determine FFT size, guard interval and PLP configuration from data embedded in the frame it was trying to decode. Frame-type signaling could be made highly reliable, but every added capability enlarged the signaling payload at the direct expense of DTV data throughput.
Cellular telephony supplied a separate direction. Zadoff-Chu sequences, valued for constant amplitude and low autocorrelation, could serve as an efficient primary synchronization signal, paired with scrambled pseudo-random secondary sequences, to let a device discover network parameters from a small, fixed slice of spectrum regardless of channel bandwidth. The 3GPP LTE E-UTRA design was mature, but built for one handset joining one cell, not to describe a family of broadcast frame types to a large and varied receiver population.
The subject invention joined them: an E-UTRA-derived metadata channel, rescaled from 72 to 64 central carriers and retimed to broadcast symbol rates, running as a parallel discovery channel alongside a DVB-T2-style frame. Frame type, FFT size and future-extension-frame status could then be signaled without enlarging the payload frame's own L1 signaling.
From "how much more fits in the preamble?" to "can discovery move into a side-channel that scales on its own?"
That is the same question ATSC 3.0's own bootstrap answers, with its own Zadoff-Chu and pseudo-random-sequence preamble sent ahead of every ATSC 3.0 frame.
A combination invention, and a claim-scope question
The landscape had already established the building blocks: in-band frame signaling from DVB-T2, and cellular-style Zadoff-Chu and pseudo-random discovery signaling from 3GPP LTE. The subject invention did not invent either. It combined them into a broadcast-specific architecture, a dedicated, rescaled metadata channel of signature sequences describing a DVB-T2-style frame family from outside that family's own preamble.
The patent's own background section is candid that this is a combination invention. The specification repeatedly frames its contribution as adapting E-UTRA modulation, developed for a different purpose, to a broadcast television context, not as a new signal-processing primitive.
The significance therefore turns on two questions. One is whether relocating cellular-style discovery signaling into a dedicated broadcast metadata channel was itself an unobvious step. The other is how closely claims drafted around DVB-T2 and E-UTRA terminology read onto a differently engineered but functionally similar mechanism such as the ATSC 3.0 bootstrap.
Standard-essentiality cuts both ways
Cerinet is a declared ATSC 3.0 licensor in both the MPEG LA ATSC 3.0 Patent Portfolio License and the Via Licensing ATSC 3.0 pool. That would ordinarily channel royalties for the '428 patent through portfolio licensing on the pools' published terms. Litigating directly against implementers, across twelve simultaneous complaints, instead follows a path already tested in this standard.
| Precedent in the same standard | What the analysis reports |
|---|---|
| Constellation Designs LLC v. LG | Infringement suit over non-uniform-constellation patents, producing a jury verdict of roughly $6.75 per NextGen TV-labeled unit, more than double the Via Licensing pool's base per-unit rate. |
| LG's response | LG cited a "challenging and uncertain patent landscape" in suspending ATSC 3.0 support from parts of its 2024 U.S. lineup. |
For the defendants here, the question is less about the underlying technique. Combining preamble-style discovery signaling with Zadoff-Chu and pseudo-random sequences is by now a widely used broadcast and cellular design pattern. It is more about claim scope: whether claims drafted around a DVB-T2 and E-UTRA hybrid architecture, conceived before ATSC 3.0's A/321 bootstrap specification was finalized, are construed broadly enough to cover that finalized bootstrap as implemented, or whether the finalized standard diverged enough in its own engineering choices to fall outside the claims' literal or equivalent scope.
An assertion that reaches transmission-equipment vendors, television OEMs and tuner suppliers in the same wave also explains why ATSC has flagged the ATSC 3.0 patent landscape as a live concern for the industry's transition timeline. Litigation risk spread across a whole hardware stack, not concentrated in one company, raises the stakes for how quickly and completely the remaining ATSC 3.0 rollout and the eventual sunset of ATSC 1.0 can proceed.
Common questions
Who is suing over ATSC 3.0?
Cerinet USA Inc. filed twelve separate complaints in July 2026, each with a jury demand, asserting U.S. Patent No. 9,253,428 B2 against thirteen defendants across the ATSC 3.0 supply chain. Each complaint pleads patent infringement under 35 U.S.C. § 271 and targets ATSC 3.0, marketed to consumers as NextGen TV, rather than any one company's product line.
Which patent is asserted?
US 9,253,428 B2, "Broadcasting system with digital television signals and metadata that modulate respective sets of OFDM carriers." It covers a COFDM broadcast scheme that signals frame structure and broadcast mode on dedicated mid-band carriers, separate from the payload carriers. The claim text has not been reviewed here.
Who are the defendants?
Rohde & Schwarz, SiliconDust USA, LG Electronics, Enensys TeamCast, Kokusai Denki Electric America and Kokusai Denki Electric (named together), Anywave Communication Technologies, Atlanta DTH, Samsung Electronics, Sony, Channel Master, Hisense and Gates Air. They span consumer-device makers, tuner and receiver suppliers, and broadcast transmission-equipment providers.
What does the '428 patent describe?
A dedicated metadata channel of 64 mid-band COFDM carriers that runs in parallel with the payload carriers. The carriers are modulated with a Zadoff-Chu sequence, which identifies the general broadcast-system type, and a pseudo-random sequence scrambled by that Zadoff-Chu sequence, which carries finer-grained mode information. A receiver can learn the frame structure, transmission mode and future-extension status before decoding any payload.
What is ATSC 3.0?
The next-generation over-the-air broadcast standard, marketed to consumers as NextGen TV.
Why does standard-essentiality matter here?
Cerinet is a declared ATSC 3.0 licensor in both the MPEG LA ATSC 3.0 Patent Portfolio License and the Via Licensing ATSC 3.0 pool, which would ordinarily channel royalties through pool licensing. Suing implementers directly follows an earlier path in the same standard, Constellation Designs v. LG, and spreads litigation risk across the whole hardware stack.
Does this article say any defendant infringes, or that the patent is valid?
No. It describes the asserted patent, the filings and the technology context. It makes no infringement, validity or enforceability determination, and no court has ruled on any of these questions here.
