220 Channel GNSS Receiver

The CHC X91+ GNSS is a compact GNSS receiver designed for high accuracy and productivity – especially in harsh environments! Powered by a TRIMBLE® BD970 core, the X91+ GNSS provides an accurate solution for any survey project.


fully integrated

Built-in GNSS engine, antenna, UHF and GSM/GPRS modules with Bluetooth® in one single unit to make your everyday work simpler, faster and better.


Optimized for network RTK

Connection to GPS or GPS+GLONASS RTK networks is made easy with our unique X91+ auto-connect feature.



The X91+ RTCM complies with major GPS brands, allowing trouble free integration into an existing pool of survey instruments. With its optional internal SATEL® Transceiver (bandwidth 403-470MHz) makes the X91+  the best priced GNSS receiver in its class!

  • 220 channels GNSS core including GPS, GLONASS, GALILEO, BeiDou (COMPASS)
  • Outstanding RTK initialization and centimeter accuracy
  • Built-in GPRS modem and UHF data link compatibility
  • Seamless compatibility with major GPS/GNSS manufacturers
  • Small, lightweight and rugged
  • Built to last with a 2 year manufacturers warranty

GNSS characteristics

  • 220 channel satellite tracking
    • GPS: L1C/A, L1C, L2C, L2E, L5
    • GLONASS: L1C/A, L1P, L2C/A, L2P, L3
    • Galileo: E1, E5A, E5B (test)
    • BeiDou: B1, B2 (optional)
  • Advanced multipath mitigation
  • Low noise carrier phase measurement

Performance specifications*

  • Real Time Kinematic (RTK)
    • Horizontal: 8mm + 1ppm RMS
    • Vertical: 15mm + 1ppm RMS
    • Initialization time: typically <10s
    • Initialization reliability: typically >99.9%
  • Post Processing (Static)
    • Horizontal: 3mm + 1ppm RMS
    • Vertical: 5mm + 1ppm RMS
    • Baseline Length: ≤300km
    • Optimized RTK output and GNSS Raw Data Recording


  • 1x RS232 serial port
  • 1x high-speed USB – Raw data download via USB connection to PC (drag and drop)
  • Integrated GSM/GPRS modem
  • Integrated Bluetooth® Class 2
  • CHC radio modem internal Rx: (Rover & Base) 430-450/450-470 MHz
  • Optional radio modems**
    • External Pacific Crest ADL Vantage Rx/Tx:
      • Tx Rate: 0.5W – 4.0W adjustable.
      • Range: up to 15km
    • External CHC DL5 Radio Tx:
      • Tx Rate: 1W-20W adjustable
      • Range: up to 25km.
      • Bandwidth: 410-430 or 430-450 or 450-470 MHz
  • Internal Satel Transceiver Rx/Tx (Base or Rover):
    • Bandwidth: 403 – 470 MHz
    • Tx Rate: 0.1, 0.5 and 1W
    • Channel spacing: 12.5 KHz – 25 KHz
    • Data speed: 9600 bps @ 25 kHz and 4800 bps @ 12.5 KHz
    • Modulation: GMSK (Pacific Crest, TrimTalk)
    • Compatible with CHC UHF Receiver
    • Typical range : ± 2 to 3 km
  • Protocols:
    • RTCM2.1, RTCM2.3, RTCM3.0, CMR, CMR+  input and output
    • NMEA0183 output
    • RINEX and HCN outputs for GNSS raw data
  • Size (LxWxH): 190 x 190 x 80 mm
  • Weight: 1.35 kg with battery
  • Operating Temp.: -40 °C to +65 °C
  • Storage Temp.: -40 °C to +75 °C
  • Humidity: 100% condensation
  • Rugedness:
    • Dustproof & Waterproof: IP67
    • Protected from temporary immersion to depth of 1 meter, floats
    • Survive 2-meter drop onto concrete


  • Power consumption: 2.6W
  • Li-ion Battery capacity : 2200mAh
  • Battery life: 9 hours (Static), typical 5 hours (RTK)
  • External power input: 9-18 VDC

Storage & Memory

  • Internal receiver memory 4GB
  • Receiver mounts as a USB external drive

Software (optional)

  • CHC’s Landstar field
  • Carlson’s SurvCE field
* Accuracy and reliability specifications may be affected by multi-path, satellite geometry and atmospheric conditions. Performances assume minimum of 5 satellites, using recommended general GNSS sensor practices.
** UHF type approvals are country specific.
*** Specifications are subject to change without notice. All trademarks are the property of their respective owners.