GPS is the most common method of synchronisation used today, However, many low-cost GPS receivers lack a pulse-per-second (PPS) signal and their time measurement usually has high latency and jitter. Fortunately, our GNSS antenna, UHURA, is designed to work with GPS, GLONASS, Galileo and BEIDOU.

UHURA provides NMEA-data using RS485 with both 4800 baud and 9600 baud. An extra line provides a latency-free, DCF77 encoded PPS signal. This makes it possible to achieve precise synchronisation of systems that would otherwise need an extra radio receiver.

UHURA can be equipped with cable lengths of up to 100m, and the connecting plug can slip through orifices of 20mm diameter. It can be fixed to vessel railings with the provided clamp and is designed to withstand strong winds and temperatures ranging from between -10 to +85°C.

UHURA is connected to the distribution box DIRC for its power supply and to enable the distribution of data. DIRC is the control centre for the OBS, ensuring optimal time synchronisation, positioning and data recovery – all within a robust, compact, lightweight, waterproof and dustproof case.

DIRC allows the user to connect a PC to both the OBS data logger and UHURA for time synchronisation and for data collection either through an SD-card or StiK port. DIRC can also accommodate an external hard drive for additional storage capacity. Finally, DIRC can establish a wireless access-point to communicate

with the data logger using any Wi-Fi enabled device.

UHURA:

• Very fast Time-to-First-Fix
• Shock-resistant
• Waterproof
• LED status indicator in a housing

DIRC:

• Waterproof
• Dustproof
• Breakproof

UHURA

• Protocol: NMEA via RS485 @ 4800 baud and 9600 baud
• Supported positioning systems: GPS, GLONASS, Galileo, BEIDOU
• Timing information: PPS-line DCF77 coded
• Power consumption: 5 Volt operation (USB)
• Cable length: up to 100 m
• Operational temperature range: -10 to +85°C
• Dimensions: Diameter – 140 mm, Height – 95 mm
• IP value: IP67

DIRC

• Ports: USB, Ethernet, SD-card, StiK, Wi-Fi
• OBS compatibility: NAMMU, LOBSTER, ISOPOD
• Memory: External hard drive, SD card reader, StiK
• Operational temperature range: -10 to +50°C
• Dimensions: Length – 228 mm, Width – 182 mm, Height – 92 mm
• IP value: IP54

• OBS and other subsea or underground systems requiring time synchronisation and data collection