## 1 Introduction
\begin{table}
\begin{tabular}{c c c c c c c} \hline
**SVN** & **PRN** & **Common Name** & **Sat. ID** & **Manuf.** & **Launch Date** & **Status** \\ \hline C201 & C19 & MEO-1 & 2017-069A & CAST & 5 November 2017 & USABLE \\ C202 & C20 & MEO-2 & 2017-069B & CAST & 5 November 2017 & USABLE \\ C203 & C27 & MEO-7 & 2018-003A & SECM & 11 January 2018 & USABLE \\ C204 & C28 & MEO-8 & 2018-003B & SECM & 11 January 2018 & USABLE \\ C205 & C22 & MEO-4 & 2018-018A & CAST & 12 February 2018 & USABLE \\ C206 & C21 & MEO-3 & 2018-018B & CAST & 12 February 2018 & USABLE \\ C207 & C29 & MEO-9 & 2018-029A & SECM & 29 March 2018 & USABLE \\ C208 & C30 & MEO-10 & 2018-029B & SECM & 29 March 2018 & USABLE \\ C209 & C23 & MEO-5 & 2018-062A & CAST & 29 July 2018 & USABLE \\ C210 & C24 & MEO-6 & 2018-062B & CAST & 29 July 2018 & USABLE \\ C211 & C26 & MEO-12 & 2018-067A & SECM & 24 August 2018 & USABLE \\ C212 & C25 & MEO-11 & 2018-067B & SECM & 24 August 2018 & USABLE \\ C213 & C32 & MEO-13 & 2018-072A & CAST & 19 September 2018 & USABLE \\ C214 & C33 & MEO-14 & 2018-072B & CAST & 19 September 2018 & USABLE \\ C215 & C35 & MEO-16 & 2018-078A & SECM & 15 October 2018 & USABLE \\ C216 & C34 & MEO-15 & 2018-078B & SECM & 15 October 2018 & USABLE \\ C217 & C59 & GEO-1 & 2018-085A & CAST & 1 November 2018 & TESTING \\ C218 & C36 & MEO-17 & 2018-093A & CAST & 18 November 2018 & USABLE \\ C219 & C37 & MEO-18 & 2018-093B & CAST & 18 November 2018 & USABLE \\ \hline \end{tabular}
\end{table} 
Table 1: BDS-3 satellite information. [PERSON] et al. [22] analyzed the stability, periodicity, and prediction precision of BDS-3e clocks. The 10,000 s stability of C32 with PHM is \(2.6\times 10^{-14}\), which is comparable to Galileo PHM and GPS IIF RAFS. As for the BeiDou-3 full operational capability (FOC) satellites, [PERSON] et al. [23] gave the early results with 11 BDS-3 MEO satellites during DOY 142-145 of 2018, which showed the 10,000 s stability is \(2\)-\(5\times 10^{-14}\). [PERSON] et al. [24] used 26 d observation data from about 100 Multi-GNSS Experiment (MGEX) and the international GNSS Monitoring and Assessment Service (iGMAS) stations [25] during DOY 030-059 in 2019 to assess the stability of BDS-3 satellite clocks. The POD adopted the one-step method with the arc of three days. The averaged 10,000 s and 86,400 s stability for BDS-3 satellite clocks was \(2.43\times 10^{-14}\) and \(2.51\times 10^{-15}\), respectively. However, the ODTS noise was not given quantitatively. Comparable stability of the PHM and RAFS seemed to be derived. Besides, [PERSON] et al. [26] gave the Hadamard derivation (HDEV) results of BDS-3 clock stability directly. This study analyzes the performance of BDS-3 satellite clocks with the ODTS noise given quantitatively. First, methodology is introduced. The ODTS product from Xi'an Research Institute of Surveying and Mapping (XRS) [27] is introduced and compared to the Wuhan University product (WUM) and the IGS final product. Then, the ODTS noise is calculated by a few ground stations which are attached to the high-precision active hydrogen masers (AHM). Afterwards, the performance of BDS-3 satellite clocks is assessed in terms of frequency accuracy, frequency drift rate, and frequency stability. Finally, the conclusion is given.