GPS World, April 2017

Inertial Ranging eLoran Wi Fi Bluetooth New Alt PNT Receiver A new series of integrated eLoran Chayka GNSS receivers emphasize low power requirements and small size for alternative positioning navigation and timing PNT to reduce risks of GNSS denial Loradd from Netherlands based firm Reelektronika consists of a receiver board of 60 x 30 x 8 millimeters consuming less than 500 milliwatts 33 volts in continuous operation The Loradd can be used with either E field or H field antennas features dual serial interface for integrated systems and is connectable to certain miniature GNSS receiver modules eLoran and Chayka are recognized as alternative PNT systems but current receivers on the market are large in comparison to miniature GNSS devices Chayka is a Russian terrestrial radio navigation system similar to Loran C It operates on similar frequencies around 100 kHz and uses the same techniques of comparing both the envelope and the signal phase to accurately determine location The first of a new series of receivers is Reelelektronikas Loradd E which is an integration of the Loradd with an E field antenna housed in a small single radome that can be connected via a data cable up to 150 meters and a dongle to a USB port on a PC The radome contains a u blox M8T GNSS receiver with antenna and measures 135 millimeters DOT Conducts Backup Study in height and 85 millimeters in diameter The Loradd E needs less than 700 milliwatts at 4 16 volts Reelektronika manufactures eLoran equipment for users service providers and surveyors The company developed the eDLoran system eDLoran works with existing Loran transmitter stations and yields differential Loran position and navigation accuracies comparable to GPS see the cover story of the July 2014 issue of GPS World The system can thus be considered as a robust backup for GPS T he U S Department of Transportation DoT is studying presponses to its November 2016 request for information concerning back up systems for GPS DoT is investigating possibilities and practicalities of using one or more positioning navigation and timing PNT technologies to ensure PNT resiliency for critical infrastructure in the event of a temporary disruption in GPS availability The filing period closed Jan 30 RFI Response Several companies responded to the RFI see https www regulations gov docket D DOTOST 2016 0227 Statements from Satelles NextNav NovAtel Allied Partners Harris UrsaNav and Orolia dba Spectracom were not made public because they contain confidential business information data Statements are available at the web page from Oakridge National Laboratory UrsaNav and iPosi SAE International the GPS Innovation Alliance and Locata Corporation which made its response openly available to kick off the necessary public discussion Senate Inquiry At a Feb 8 Commerce Committee hearing Sen Roy Blunt asked DoT Inspector General Calvin Scovel about progress on GPS back up which DoT and the Deputy Secretary of Defense announced they would be working on in 2015 Scovel responded with information about the Federal Aviation Administrations next gen plan which did not address the question Sen Blunt then asked Scovel to submit a written answer for entry into the final record of the hearing My question for the record will be that this commitment made in 2015 concerned about the current dependency that so many people have with GPS is Are they moving forward with a backup system if the current GPS system goes down ELORAN CHAYKA CRITICAL INFRASTRUCTURE 10 GPS WORLD WWW GPSWORLD COM APRIL 2017 LORAD CORE an alternative PNT source to combat GNSS denial 60 x 30 x 8 millimeters LATE BREAKING NEWS Indoor Synchronization Orolia synchronized a Spectracom SecureSync high precision time server with the new Iridium Satelles Satellite Time and Location signal in several challenging indoor locations using a low Earth orbit satellite based signal one thousand times stronger than GPS See gpsworld com for details Read a full account in our May issue