A fully scalable wireless seismic recording system with real-time data transmission for conventional surveys and passive monitoring projects NOW features new hardware developed to significantly reduce power consumption.
RT2 is a revolutionary cable-free and real-time seismic data acquisition system that
- scales to tens of thousands of channels,
- delivers, at scale, the flexibility and reduced operating costs inherent in cable-less systems, and
- includes data security and data visibility—well understood advantages of real-time cabled systems.
Seismic contractors no longer have to risk compromising the quality and the security of their data to access a high channel-count, cable-less system.
RT2 is designed and engineered to overcome the limitations of the currently available seismic recording systems and to deliver a reliable, cost-effective, easy-to-use solution for both conventional and unconventional seismic operations.
RT2 advances the way seismic data are acquired onshore
- by taking advantage of highly efficient radio technologies, instead of bulky, heavy, unreliable cables, and
- by overcoming the data QC, collection, transcription, and security limitations of ‘blind’ nodal systems.
REDUCED POWER CONSUMPTION
- RT2 now features new hardware developed to significantly reduce WRU power consumption on seismic data acquisition projects worldwide.
- Reduced power consumption means up to 50% fewer batteries on each crew, resulting in less capital expenditures and greater efficiencies.
- One fully charged standard 6-cell battery will now operate a WRU for 25+ days (assuming a 12-hour workday) and two fully charged standard 6-cell batteries for over 50 days.
- Backward compatible with a simple firmware update.
The RT2 software has been designed from the ground up to deliver a fully featured user interface that has the “look and feel” of a cabled system with support of real-time data collection and spread management. The user can be confident that the expected seismic data is being collected via instant feedback from the RT2 spread manager and the areal seis-monitor. Attributes from daily tests, battery status, and telemetry status are always available to the user or they can be updated on demand. While the RT2 Central mimics the typical features of cabled telemetry systems, Wireless Seismic has also added many capabilities that make the RT2 a truly unique seismic recording system.
RT2 features a robust Hybrid Radio Telemetry system that enables your seismic data acquisition project to continue, uninterrupted, even if radio connectivity is temporarily lost over portions of the spread. The standard operating mode for RT2 is real-time wireless recording with auto skip-healing, should any WRUs lose radio connectivity. With the hybrid telemetry mode, if radio connectivity is partially lost and auto skip-healing cannot overcome the immediate problem, then “stranded” WRUs will immediately switch to operating autonomously, buffering their seismic data into local flash memory. When radio connectivity is restored, buffered seismic data are wirelessly transmitted back to the Central recorder. Alternatively, autonomous recording can be user-selected at any time—where data will be buffered into local flash memory while real-time QC data continues to stream to the Central. The buffered seismic data can then be collected wirelessly at the operator’s convenience.
The Line Interface Unit (LIU) is a critical component of the RT2 data communications infrastructure and fulfills several important functions as part of the system. The LIUs:
- Collect the real-time seismic data that passes along a line of Wireless Remote Units (WRUs) and forwards onto an Ethernet-based backhaul telemetry subsystem for transmission to the Central recording system.
- Provide clock discipline to each line segment of WRUs, which allows the WRU to switch off its GPS subsystem after the GPS has acquired the WRU’s position, saving significant WRU battery power. Each LIU disciplines its clock to GPS and then provides synchronization via the radio to discipline the WRUs.
- Act as “traffic cops” for outbound commands from the Central, distributing these messages to the WRUs on each line segment, and for any inbound spread data and status information responding to requests from the Central.
The LIUs are physically located at strategic points along lines or line segments of WRUs and communicate with the WRUs on the same patented 2.4 GHz radio telemetry. The LIU would typically be located in the center of the line, but can be located anywhere on the line that supports good backhaul connectivity and crew logistics. An LIU can support up to 2000 (1000 per side) single-channel stations in a near real-time data collection mode and/or several hundred WRUs on one line segment in continuous real-time data collection mode, depending on the recording sample rate and other factors.
The Wireless Remote Unit, or WRU, is the heart of the RT2. These small units contain a complete seismic acquisition and radio relay system inside the waterproof aluminum case. The analog-to-digital converter is state of the art, one that has been widely adopted by most manufacturers of seismic systems because of its outstanding analog performance and low power consumption.
The WRU contains an orientation sensor. When carried by its attached rope, its power is off and can be laid flat for transport. To power up the unit, the user holds it vertical for a few seconds. It rapidly performs a series of tests when placed on the ground, locates its position with the internal GPS, and establishes radio communication with its neighbors on the line. To turn it off, just pick it up by its attached rope. The advantage of this system is that the least-skilled personnel can deploy the WRUs without using complex keyboard/display devices. The LED status indicators on the unit provide complete, easy-to-interpret diagnostics.
The WRU runs from either one or two rechargeable lithium-ion batteries. In the two-battery configuration, its intelligent power management system initially chooses the battery with the least amount of charge available. When this battery is depleted, the system switches to the higher capacity battery. Depleted batteries can be replaced in the field, but in most field operations, the batteries will last until the WRU is picked up. The status of the batteries is monitored continuously from the Central recording system, and LED indicators tell the field crew which batteries to replace first.
If radio connectivity is partially lost, the Hybrid Radio Telemetry immediately allows stranded WRUs to switch to operating autonomously, buffering data into local flash memory. When radio connectivity is restored, buffered data are wirelessly transmitted to the Central recorder.
THE WRU BATTERY PACK AND CHARGER
The WRU battery pack is a fully contained smart battery with a choice of capacities to meet the needs of modern 2D, 3D, and passive seismic surveys. The charge circuitry is contained within the pack, so no special chargers are required. Five volts are supplied to the pack for charging. One tri-color LED indicates the charge state — charging, charged, or out of temperature range for charging. The WRU can interrogate 19 available attributes from the battery pack. These battery packs have been specifically designed to yield the maximum number of charge cycles for years of dependable use in the field.
The WRU battery charger is specifically designed to provide high density charging with a small physical footprint. The charger includes 10 self-contained charging drawers, each with its own power supply to charge the battery packs. One charging station can charge 80 fully discharged standard batteries in 8 hours and high-capacity batteries in 12 hours from a standard electrical service.