Timing Solutions for Broadcasters

  • aPNT and ZTA for timing and synchronization in Broadcast - $15

    Date: April 3, 2024
    Topics: ,

    Highly accurate timing is a mission-critical requirement for the synchronization of the broadcast domain. Employing multiple-source resiliency enables the ability to function for extended periods of time without GPS/GNSS reference, which is a requirement of US Federal Executive Order 13905. This executive order lays out the requirements and where they apply in relation to critical infrastructure. In this paper, we will address the specifics of FEO 13905 as well as what a robust assured positioning, navigation and timing (aPNT) solution can look like.

    Emphasizing the critical role of timing and synchronization in essential infrastructure is imperative. This emphasis has prompted a comprehensive evaluation of the vulnerabilities inherent in existing time sources. This paper aims to delve into these risks and explore potential solutions to safeguard critical infrastructure. It will also touch upon the U.S. government’s efforts in securing Positioning, Navigation, and Timing (PNT) and the significant recommendations stemming from this initiative. The secure PNT objective is to address the escalating frequency of Global Navigation Satellite System (GNSS) outages, which have left users seeking alternative solutions.

    We will explore the potential impact of these threats on various aspects of content generation, processing, and distribution, particularly in the TV broadcast industry. We will also discuss the role that the broadcast industry can play in implementing potential solutions. The discussion will introduce the concept of Zero Trust architectures (ZTAs), their implementation, and the variety of time sources available today, as well as those currently in development. These alternatives include network protection schemes and highly stable oscillators, as well as multi-constellation/multiband GNSS receivers, anti-jamming and anti-spoofing solutions and other emerging alternatives like Low Earth Orbit (LEO) satellite networks and next-generation broadcast networks. The objective is to inform and equip users with the tools available to counteract common threats such as GPS interruptions, GPS degradation, GPS service denial, and GPS spoofing.

    Rick Knea | Oscilloquartz SE | Nampa, Idaho, United States

  • Is Synchronous Ethernet a Must Have or just a Gimmick for the Broadcasting Industry?  - $15

    Date: April 3, 2024
    Topics: ,

    Over the last few years, the Precision Time Protocol (PTP) has evolved to become the preferred method of choice for accurate time transfer over Ethernet networks for every application domain. PTP being an IEEE standard (IEEE1588) has helped but was by no means the only reason for this development. Semiconductor and device manufacturers alike have been adding PTP hardware support to their network products – a mandatory requirement to reach sub-µs accuracies. Most importantly, PTP can be tailored to the specific requirements of an application domain via PTP Profiles – a feature many industries made extensive use of. The All-IP Studio, for example, uses the PTP broadcasting profile (SMPTE ST 2059-2) for accurate time transfer.

    As a physical transport medium, Ethernet has superseded legacy solutions which were commonly used for many applications in the past. Ethernet is inherently asynchronous with only two adjacent nodes being synchronized with each other. This feature greatly simplifies deployment and maintenance and was possibly the driving factor of its success. When it comes to time and frequency transfer there is an obvious drawback. Accurate time must be transferred via a constant stream of packets, while frequency transfer cannot. Every end node must regenerate the frequency derived from the time information. This method has proven to be sufficiently accurate for many applications and is widely deployed, yet it has its limits concerning overall accuracy. If the quality of the time information deteriorates, the quality of the re-generated frequency will suffer as well. Specifically-optimized digital phase-locked loops can mitigate that effect but only to a certain extent. If end devices require accurate as well as highly stable frequencies for their operation, this limitation must be carefully considered.

    To circumvent this problem, the local synchronicity of Ethernet can be extended to provide a common frequency for the complete network. How can this be accomplished? Whenever two devices establish a communication channel via a physical medium, a transport frequency must be provided by either of the two nodes to which the other must synchronize to. In standard Ethernet, the selection of the respective devices taking over that role is arbitrary. If, however, the selection process is made user-definable, a common frequency can be propagated through the complete network.

    In this paper, we will describe synchronous Ethernet’s (SyncE’s) basic principles as specified by ITU. We will highlight the prerequisites of network devices to comply with SyncE requirements. Furthermore, we will focus on the software and system aspects of deploying and maintaining a SyncE network. Special consideration will be taken on how to best combine SyncE and PTP to improve both the accuracy and the resiliency of time and frequency transfer. Although SyncE was primarily designed to provide highly accurate time and frequency for modern telecom applications, we will analyze whether and to which extent the broadcasting industry can benefit from this technology. The paper concludes with real-world measurement in networks with SyncE and PTP support. We will highlight its performance under different operating conditions and demonstrate the impact of different failure modes. We will compare the performance of PTP with SyncE-assisted PTP.

    Nikolaus Kerö | Oregano Systems; Nvidia; European Broadcasting Union | Vienna, Austria; Geneve, Switzerland
    Thomas Kernen| Oregano Systems; Nvidia; European Broadcasting Union | Vienna, Austria; Geneve, Switzerland
    Ievgen Kostiukevych | Oregano Systems; Nvidia; European Broadcasting Union | Vienna, Austria; Geneve, Switzerland

  • Leveraging traditional GNSS time servers for resiliency and interoperability in Broadcast Positioning System (BPS)  - $15

    Date: April 3, 2024
    Topics: ,

    As a complement to existing Positioning, Navigation and Timing services, the Broadcast Positioning System (BPS) requires proper time synchronization in each of the base stations for proper operation. The shared time reference in the different stations combined with their known locations, allows the triangulation needed for positioning and provides a trusted time reference to users benefiting from this system. In order to maintain a traceable and accurate time synchronization, different features supported by traditional GNSS time servers can help, easing and expediting the deployment of these systems.

    Francisco Girela Lopez | Safran Electronics and Defense | Rochester, N.Y., United States
    Mark Corl | Triveni Digital, Inc. | Princeton, N.J., United States
    Alexander Babakhanov | Avateq Corp. | Markham, Ontario, Canada