GLONASS Only and BeiDou Only RTK Positioning

As a world leader in GNSS positioning, Leica Geosystems attaches great importance not only to combined GNSS solutions, but also to individual system performance. After successfully dealing with GLONASS inter-frequency biases in terms of ambiguity resolution (Takac, 2009) and GNSS interoperability (Takac et al., 2012), it is possible for the first time to provide reliable GLONASS only RTK solutions. In addition, considering that the BeiDou system allows operational positioning services over the Asia-Pacific region, it is reasonable to assess the quality of BeiDou only RTK positioning with the latest SmartWorx 5.50 firmware of Leica Viva GNSS. This paper analyzes the performance of the individual systems in the measurement and position domains. The measurement domain analysis focuses on satellite geometry and signal strength, whereas the position domain analysis is performed at three accuracy levels, namely, navigation position, differential code position and high precision position with fixed ambiguities. Moreover, different observational environments such as open sky and canopy are taken into account. Compared with GPS only and combined GNSS solutions, the performance of GLONASS only and BeiDou only RTK positioning is assessed with respect to availability, accuracy, reliability of coordinate quality (CQ) indicator and time to fix. The presented results serve as an informative basis for applications where GLONASS only or BeiDou only positioning is required or desired. Using technologically innovative approaches, Leica Geosystems provides the most reliable GNSS position solution to meet the demands of RTK applications in all environments.