Dual-Frequency RTK GPS Receiver
Hemisphere GPS offers the dual-frequency R220 GPS receiver, a 39-channel that offers real-time kinematic (RTK) operation with 12 channels of L1 C/A code, 12 channels of L1 P-code, and 12 channels of L2 P-code tracking. The other three channels can be used for tracking satellite-based augmentation systems including OmniSTAR’s commercial HP and XP differential correction services or three additional channels of L1 C/A-code tracking. The unit measurements are: height, 45 millimeters (1.77 inches), width 114 millimeters (4.49 inches), length 160 millimeters (6.3 inches), and weight 0.54 kilgrams (1.19 pounds). The unit is intended for professional mapping, guidance, machine control, and navigation applications. Integrated L-Band tracking powers down when not in use, and OmniSTAR subscriber access permits remote activation via satellite. The R220 incorporates Hemisphere GPS’s COAST technology, which maintains accurate solutions for 40 minutes or more after loss of a differential signal, according to the company. A position output rate of 10 Hz is standard but up to 20 times per second is available, as is raw GPS data output. The unit uses a standard USB Flash drive for data logging. Hemisphere GPS, Calgary, Alberta, Canada.