CSNO (2018a) Development of the BeiDou navigation satellite system (version 3.0). http://www.beidou.gov.cn/xt/gfxz/201812/P020190117356387956569.pdf. Accessed 9 Feb 2020 The skill description is somewhat misleading. The Press skill has the same functionality as the Hold skill (including the shield and energy storing), but only during a very brief window. The frequency resolution is chosen such that the frequency bin size is less than (2/3) × T coh, where T coh is the coherent integration time. In case of a 5 ms integration time, the frequency bin size should be less than or equal to 133.33 Hz. Tegedor, J.; Øvstedal, O. Triple carrier precise point positioning (PPP) using GPS L5. Surv. Rev. 2014, 46, 288–297. [ Google Scholar] [ CrossRef] Shamaei, K.; Kassas, Z.M. Receiver design and time of arrival estimation for opportunistic localization with 5G signals. IEEE Trans. Wirel. Commun. 2021, 20, 4716–4731. [ Google Scholar] [ CrossRef]

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Duan B, Hugentobler U, Selmke I (2018) The adjusted optical properties for Galileo/BeiDou-2/QZS-1 satellites and initial results on BeiDou-3e and QZS-2 satellites. Adv Space Res 63(5):1803–1812. https://doi.org/10.1016/j.asr.2018.11.007Banville, S.; Collins, P.; Zhang, W.; Langley, R.B. Global and Regional Ionospheric Corrections for Faster PPP Convergence. NAVIGATION J. Inst. Navig. 2014, 61, 10. [ Google Scholar] [ CrossRef] Bruyninx C, Kenyeres A, Takacs B (2002) EPN data and product analysis for improved velocity estimation: first results. IAG Symp Ser 125:47–53 Cheng M, Ries J (2017) The unexpected signal in GRACE estimates of C20. J Geod 97(8):897–914. https://doi.org/10.1007/s00190-016-0995-5 Sidorov, D.; Dach, R.; Prange, L.; Jäggi, A. Advancing the Orbit Model for Galileo Satellites during the Eclipse Seasons; EGU General Assembly: Vienna, Austria, 2018; Available online: https://boris.unibe.ch/116170/1/DS_EGU2018.pdf (accessed on 10 November 2020).

Series, M. Recommendation ITU-R M.1903-1, 2019. Available online: https://www.itu.int/dms_pubrec/itu-r/rec/m/R-REC-M.1903-1-201909-I!!PDF-E.pdf (accessed on 29 June 2023). Arnold D, Meindl M, Beutler G, Dach R, Schaer S, Lutz S, Prange L, Sośnica K, Mervart L, Jäggi A (2015) CODE’s new solar radiation pressure model for GNSS orbit determination. J Geod 89(8):775–791. https://doi.org/10.1007/s00190-015-0814-4 In case of BeiDou GEO satellites which transmit D2 navigation signal, there is no NH code modulation on top of the data bits. But, D2 signal has a data bit rate of 500 bps, meaning that each data bit will last for 2 ms. Therefore, the bit transition in case of BeiDou D2 signal may occur after every 2 ms unlike the GPS L1 C/A signal, where the bit transition may occur only after 20 ms. In view of this much frequent sign transition occurrences, a similar strategy like D1 signal acquisition technique is implemented for BeiDou D2 signal. The implementation strategy for D2 signal acquisition is described in the following. Step 1:The shield created by this skill lasts for a short duration even after the skill button is released, allowing the skill's DMG to trigger the effects of Geo Resonance.