B2X: The Convergence of Broadcast and Broadband for a Multicast Future
The Challenge of Connectivity in a Streaming-First World
Across the globe, mobile networks are experiencing a surge of pressure unlike anything in communications history. Video traffic alone accounts for more than 70% of mobile network usage and continues to grow exponentially. Software updates, real-time maps, AI model distributions, and interactive content services further drive congestion. The unicast foundation of today’s mobile networks, while ideal for two-way communication and personalized experiences, was not built to scale for this tidal wave of one-to-many data delivery.
Broadcast infrastructure, on the other hand, was purpose-built for this very purpose. It excels at delivering the same content to many users simultaneously. But until now, it has been siloed – powerful yet disconnected from the mobile ecosystems and intelligent service management layers that power today’s devices.
What if we could merge these two worlds? What if we could unify the deterministic efficiency of broadcast with the intelligent, IP-native architecture of mobile broadband? That is the story of B2X.
B2X: A New Chapter in Wireless Communications
B2X, short for “Broadcast-to-Everything,” is a breakthrough standard built upon the solid foundation of ATSC 3.0—a foundation that was architected from the start for extensibility. ATSC 3.0’s bootstrap signaling, flexible data framing, and modular architecture were designed with foresight, enabling future evolution without disrupting backward compatibility. B2X represents that evolution.
Operating as a new physical layer and network layer addition to ATSC 3.0, B2X introduces fully integrated multicast and broadcast capabilities aligned with 3GPP specifications. It does so in a way that complements, not replaces, the existing linear television services delivered by today’s broadcasters. In this sense, B2X can be seen as an enhancement set that builds alongside the current A/300 series standards, rather than overriding them.
ATSC 3.0 continues to support the core paradigm of free-to-air television, including NextGen TV services, advanced emergency alerting, and UHD video. But B2X extends this foundation to support new multicast and datacasting applications through seamless technical alignment with 5G and 6G network architectures.
B2X is not a proprietary patch or retrofit workaround. It is a purpose-built system designed to operate in parallel with conventional ATSC 3.0 deployments. B2X signals can be interleaved with traditional ATSC content using shared infrastructure and common SFN topologies. In effect, the broadcast plant becomes a dual-use network: continuing to serve traditional households while opening vast new opportunities in wireless broadband and data delivery.
The Architecture: Where ATSC and 3GPP Meet
At the heart of B2X is a harmonized architecture that operates across all layers of the stack:
Physical Layer: Built on OFDMA principles, B2X uses 3 kHz subcarrier spacing and operates over 5–50 MHz channels. Timing is governed by 1000ms virtual frames synchronized via GPS or IEEE 1588 PTP—allowing alignment with mobile frames for hybrid scheduling. These frames are logically and temporally separated from traditional ATSC payloads yet coexist within the same spectral channel and transmission infrastructure.
MAC and Data Link (Layer 2): Introduces full PDCP encapsulation and signaling interworking via the 3GPP Option 4 Dual Connectivity model (TS 37.340). This is the same mechanism that lets 5G and LTE work seamlessly. It enables seamless 5G onload/offload workflows while maintaining compatibility with ATSC’s foundational design. ATSC receivers that lack B2X capability simply ignore the new slices. PDCP encapsulation also means that 5G content delivered over broadcast looks the same to a handset as content delivered over the 5G RAN.
Network Layer (Layer 3): At this layer, B2X adds multicast and broadcast capabilities to 5G. Stateless multicast IP flows remove the need for session setup. Service discovery, filtering, and application registration are managed via lightweight, programmable signaling.
Integration Points:
- Works natively with O-RAN F1-C/D and eCPRI interfaces.
- Supports hybrid CU/DU deployments in cloud-native environments.
- Interoperable with 5G NEF/PCF policy functions.
By preserving the original ATSC 3.0 service layer while adding this new standards-aligned multicast transport layer, B2X creates a bridge for broadcasters to participate in both legacy and next-generation ecosystems.
Why It Matters Now
The mobile industry faces a fundamental constraint: spectrum is finite, and user demand is not. With 5G’s move toward ultra-low latency and massive machine-type communications, mobile operators must find ways to offload high-throughput, downlink-heavy services. Enter B2X.
B2X delivers massive content payloads via broadcast, freeing mobile bandwidth for latency-sensitive and uplink-intensive applications. It delivers:
- Live video to mobile users.
- AI model and software updates to edge devices.
- Smart city sensor payloads.
- Emergency alerts and public safety information.
- Multicast content for cars, homes, and handsets.
- PNT related services based on Broadcast Positioning System (BPS)
- Enhanced GPS (e-GPS) offering real-time kinematic solutions and distribution
Unlike 5G Broadcast (FeMBMS) or 5G MBS, B2X adds multicast capability and added spectrum at the same time. B2X does not rely on cellular spectrum. Its transmission efficiency is up to 30% higher than mobile-based approaches due to optimized framing and signaling. And it can scale to millions of receivers without adding signaling overhead.
A Foundation Designed for Tomorrow
The bootstrap signaling in ATSC 3.0 was not an accident. It was a design choice for the future. By allowing receivers to discover where in time and frequency to wake up, this signaling now becomes essential to low-power B2X device acquisition.
Similarly, ATSC’s Physical Layer Pipes (PLPs) were conceived to allow logical separation of services. B2X uses this concept to deliver dynamic slices with application-specific content, allowing ATSC to carry broadcast television and IP-multicast payloads side-by-side.
In short, B2X is not a break from ATSC. It is the realization of its latent potential.
Strategic Momentum and Global Pathways
B2X is more than a technical solution—it’s a strategic lever.
In India, ATSC 3.0 and B2X are the backbone of the Direct-to-Mobile (D2M) program. Backed by government support, it paves the way for chip-level integration in mobile phones, unlocking global scale.
In Brazil, ATSC 3.0 adoption enables a B2X-ready platform for smart city services, media delivery, and disaster resilience.
In the U.S., Sinclair/ONE Media is leading the charge by aligning broadcaster infrastructure with 5G/6G roadmap priorities, turning broadcast spectrum into a next-gen delivery network.
The ATSC and 3GPP processes are already in motion. A/400 family specifications are in development, and partnerships for real-world PoCs are underway with device OEMs, MNOs, and cloud vendors.
Business Impact: Shared Value Across Ecosystems
For mobile operators, B2X delivers operational relief, capital efficiency, better QoE, and reduced unicast pressure.
For broadcasters, B2X opens new revenue streams: wholesale data delivery, CDN partnerships, smart city contracts.
For device makers and consumers, it ensures scalable access to content without added cost or complexity.
B2X monetizes spectrum, elevates broadcast’s relevance, and positions the industry as a key partner in the 6G future.
Conclusion: ATSC 3.0, Reinvented for the Data Age
ATSC 3.0 was built for extensibility. B2X brings that vision to life.
B2X transforms ATSC 3.0 from a powerful but purpose-specific television standard into a fully networked, standards-aligned platform for universal IP and PDCP delivery. It operates seamlessly alongside conventional broadcast, respects backward compatibility, and delivers multicast at global scale. It’s an incredible engineering achievement.
For broadcasters, it means relevance in a broadband world. For telecoms, it means scale without strain. For consumers, it means a future where video, data, and critical services arrive efficiently, reliably, and universally.
This is the beginning of a new era—where broadcast and broadband are not competitors, but co-conspirators in a more connected world.