The intra-system biases, including differential code biases (DCBs) and differential phase biases (DPBs), are generally defined as the receiver-dependent hardware delays between different frequencies in a single global navigation satellite system (GNSS) constellation. Likewise, the inter-system biases (ISBs) are the differential code and phase hardware delays between different GNSSs, which are of great relevance for combined processing of multi-GNSS and multi-frequency observations. Although the two biases are usually assumed to remain unchanged for at least 1 day, they sometimes can exhibit remarkable intraday variability, likely due to environmental factors, particularly the ambient temperature. It has been proved that the possible short-term temporal variations of receiver DCBs and DPBs are directly related to ambient temperature fluctuation. We analyze whether the variability of the biases is sensitive to temperature and further identify how this affects the performance of real-time kinematic (RTK) positioning. Our numerical tests, carried out using GPS, BDS-3, Galileo and QZSS observations collected by zero and short baselines, suggest two major findings. First, we found that while ISBs associated with overlapping frequencies are fairly stable, those associated with non-overlapping frequencies can exhibit remarkable variability over a rather short period of time, driven by the changes of ambient temperature. Second, by pre-calibrating and modeling of the biases for the baselines at hand, the empirical success rates and positioning performance can be significantly improved when compared to classical and inter-system differencing, with both models assuming time-invariant receiver DCBs, DPBs and ISBs.

中文翻译：

---

关于多个GNSS系统内和系统间偏差的温度敏感性及其对RTK定位的影响

系统内偏差（包括差分代码偏差（DCB）和差分相位偏差（DPB））通常定义为单个全球导航卫星系统（GNSS）星座图中不同频率之间的接收方相关硬件延迟。同样，系统间偏差（ISB）是不同GNSS之间的差分代码和相位硬件延迟，这对于多GNSS和多频率观测的组合处理非常重要。尽管通常假定这两个偏差至少保持1天不变，但有时可能会显示出明显的日内变化，这可能是由于环境因素（尤其是环境温度）引起的。已经证明，接收器DCB和DPB可能的短期时间变化与环境温度波动直接相关。我们分析了偏差的可变性是否对温度敏感，并进一步确定了它如何影响实时运动（RTK）定位的性能。我们使用零基线和短基线收集的GPS，BDS-3，伽利略和QZSS观测值进行了数值测试，得出了两个主要发现。首先，我们发现，尽管与重叠频率相关的ISB非常稳定，但与非重叠频率相关的ISB在相当短的时间内会受到环境温度变化的影响而表现出显着的可变性。其次，通过对现有基准的偏差进行预校准和建模，与经典差分和系统间差分相比，这两种模型均假设时不变的接收器DCB，从而可以显着提高经验成功率和定位性能。