A couple of years ago Skytraq launched the NavSpark mini, a tiny (17x17mm) GPS module, that sold for $6. However, the company has now launched an even smaller module called Skytraq PX1122R, which measures at just 16x12mm, and offers support for GPS, Galileo, GLONASS, and Beidou signals, as well as Real-time Kinematic (RTK) relative positioning technique that enables 1-3cm positioning accuracy.
The Skytraq PX1122R RTK GNSS module key features a SkyTraq PX100 Phoenix GNSS chipset. It Supports GNSS standards & bands – GPS L1/L2C, Galileo E1/E5b, Beidou B1I/B2I, GLONASS L1/L2, QZSS L1/L2C. Its Integrated RTK offers 1cm + 1ppm RTK accuracy in seconds (under 10 seconds), enhancing the precision of position data derived from satellite-based positioning systems. The module enables Up to 10Hz quad-GNSS RTK update rate. The module also enables Base or rover, which have a mode configurable. The module offers 3V LVTTL level for serial interface, 24x castellated holes with UART, RF input, 1PPS, Reset, 3.3V, GND (most pins not in use). Input Voltage clocks at 3.3V DC +/‐10%, while consuming 50mA of current. It is 16 x 12.2 mm in dimension, and weighs 1.7 grams, with a temperature Range of ‐40°C ~ +85°C.
Application to the module’s centimeter-level precision includes: agriculture, machine control guidance (UAV), survey and GIS data collection, structure, and deformation monitoring. RTK applications need a base and a rover. The base can be a third-party RTK base station service, or a configured PX1122R module. The PX1122R module is also suitable for PPP services like OPUS, AUSPOS, CSR-PPP. This functions by presenting a dual-frequency RINEX log file converted from carrier phase raw measurement log file of a single PX1122R.
The company provides a breakout board to help get started with the module, and also PX1122R-EVB “PX1122R Multi-Band Quad-GNSS RTK Evaluation Board” with USB, UART, and Bluetooth SPP (Serial Port Profile) interface. The Bluetooth SPP interface enables rover NTRIP client connection to remote non-line-of-sight RTK base through a smartphone connected to the Internet and running a mobile app like ArcPad or Esri Collector.