The space segment of the Global Navigation Satellite System (GNSS) is equipped with highly stable atomic clocks. In order to use these clocks as references, their time offsets must be estimated from ground measurements as accurately as possible. This work presents a multi-frequency and multi-constellation method for estimating satellite and receiver clock corrections, starting from unambiguous, uncombined, and undifferenced carrier-phase measurements. A byproduct of the estimation process is phase biases (i.e., the hardware delays of the carrier-phase measurements occurring at receivers and satellites).

中文翻译：

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一种改进 GNSS 时钟校正和相位偏差长期估计的多频方法

全球导航卫星系统（GNSS）的空间部分配备了高度稳定的原子钟。为了使用这些时钟作为参考，它们的时间偏移必须尽可能准确地从地面测量中估算出来。这项工作提出了一种用于估计卫星和接收器时钟校正的多频率和多星座方法，从明确的、未组合的和无差异的载波相位测量开始。估计过程的一个副产品是相位偏差（即在接收器和卫星上发生的载波相位测量的硬件延迟）。