The LNRClok-1500 is a smart, low cost, low noise, and compact GPS/GNSS-disciplined Rb oscillator (GPSDO) with an optional integrated GPS / GNSS receiver, using u-Blox's advanced 50-channel LEA-6T GPS receiver with a 6-position engine and anti-jamming technology. It's GNSS ready to support multi-navigational satellite system receivers, including GPS, Galileo, GLONASS, IRNSS, and BDS / COMPASS. It is compatible to the Stanford PRS10 model and fits in a compact 1U chassis. The LNRClok uses the patented, adaptive SmarTiming+ technology, disciplining the GPS/GNSS reference at 1ns resolution, providing a host of complex time and frequency features in one package solution, while achieving state-of-the-art performance, reliability and extended lifetime.