For configuring time-synchronous infrastructure supporting Private 5G and O-RAN base station 5G mobile services
Anritsu Corporation has upgraded the synchronous measurement function for its Network Master Pro MT1000A, a small in-class tester supporting mobile networks up to 100 Gbps. Fifth-generation (5G) networks are expected to support increasing future numbers of applications and services, such as hi-definition video streaming, autonomous driving, IoT sensing, smart factories, etc. By upgrading this MT1000A test function, Anritsu hopes to facilitate the construction of time-synchronous infrastructure, a key technology supporting 5G networks.
The MU100090B is a GNSS disciplined oscillator supporting GPS, Galileo, GLONASS, Beidou and QZSS. It receives signals from each of these GNSS to output a UTC-traceable reference time signal as well as 10-MHz signals as a time-synchronous, high-accuracy reference timing supplied to the portable MT1000A, supporting SyncE Wander and PTP tests up to 25 Gbps for measuring network time synchronisation.
Furthermore, multiple MT1000A testers at various remote sites can be operated and monitored from the central office using the Site Over Remote Access MX109020A (SORA) software to help quickly pinpoint synchronisation problems.
Development Background
Deployment of 5G communications networks is spreading due to the advantages of ultra-high speeds, high reliability, low latency and multiple simultaneous connections in various scenarios. The millimetre-wave (mmWave) band used by 5G technology employs the Time Division Duplexing (TDD) technology for managing the timing of uplink and downlink signals. This technology requires that the time at all base stations is precisely synchronised, otherwise, interference will cause degraded communications quality. Moreover, achieving a “smart” IoT-based society will require cooperation between devices exchanging position information acquired using Observed Time Difference Of Arrival (OTDOA) positioning technology, which is ideal for IoT applications, but high-accuracy position measurement is impossible without high-accuracy time synchronisation between base stations.
Base stations can be synchronised using wired-network technologies called Synchronous Ethernet (SyncE) and Recision Time Protocol (PTP), which require both measurements of the network time-synchronisation performance when installing and maintaining a cell site, along with guaranteed network performance by the network operator.
Moreover, the O-RAN Alliance, which is a mainstream promoter of base-station multi-vendors, increasingly requires tests of overall mobile network time-synchronisation performance to assure interconnectivity.
Time-synchronisation quality is indicated by drift from coordinated universal time (UTC), so precise time-synchronisation measurement requires expensive infrastructure to acquire UTC with high accuracy. This can be a challenge at the installation and maintenance of many cell sites.
Anritsu has developed many test instruments for measuring the jitter and wander of transport networks since the SDH/SONET era. Adding this new High-Performance GNSS Disciplined Oscillator MU100090B to the line of modules for the portable, battery-operated MT1000A will help simplify on-site I&M time-synchronisation tests.
Key Features
- High-accuracy multiband measurement: Interference caused by the ionosphere between the antenna and a satellite is a major cause of noise and inaccuracy. Since the MU100090B can simultaneously receive signals in two frequency bands from GNSS, it can self-correct for these ionospheric errors.
- Convenient on-site support for multiple GNSS: At least four satellites must be visible to capture the reference timing with high accuracy from the GNSS. Adding other national satellite systems in addition to the U.S. GPS greatly improves the accuracy of the captured reference timing. Using the MU100090B with other satellites, such as GLONASS and Galileo, makes it easy to capture a precise reference timing.
- Short warm-up time and high stability: Holdover signals from satellites are easily affected by external factors causing extreme short-term instability in timing data. The MU100090B has a function for learning GNSS timings to estimate and output the optimum timing for time-synchronisation measurement via the built-in rubidium oscillator.
In comparison to the earlier MU100090A model, a revision of this learning algorithm has cut the warm-up time by more than one-quarter, helping improve the efficiency of measurement work.
Moreover, the Holdover stability is also improved, which is useful for time-synchronisation tests at locations where satellites are not visible, such as in underground malls, stadiums and equipment cabinets.
Target Markets: Communications operators, network installers and communications equipment vendors
Applications: Installing, maintaining and troubleshooting communications networks, a simple evaluation of communications equipment
