Delta-Differential One-Way Ranging (or Delta-DOR, Δ-DOR for short) is an interplanetary radio-tracking and navigation technique.[1]
How it is done
editRadio signals from the spacecraft are received by two widely separated deep-space ground stations on Earth and the difference in the times of signal arrival is precisely measured[2] (and used to calculate a bearing[citation needed]). This is corrected using information about the current delays due to Earth's atmosphere, obtained by simultaneously tracking (from each ground location[3]) radio signals from a quasar (within 10 degrees of the same direction[3]).[2]
NASA uses its Deep Space Network to pick up signals from the spacecraft that tell navigators where the spacecraft are located. This navigation service is called "tracking coverage" and it includes Doppler, ranging and delta differential one-way ranging, or "Delta DOR."[1] [4]
ESA has the ESA Deep Space Network, China has the Chinese Deep Space Network and India has the Indian Deep Space Network.
Missions that used it
editΔ-DOR navigation has been used by number of NASA planetary missions. Other space agencies have also used the technique, on missions such as:
ESA used a Δ-DOR system for Venus Express' orbit insertion in April 2006 and to Rosetta's Mars swingby in February 2007. The technique was also used in guiding the ExoMars Trace Gas Orbiter during its cruise phase in 2016.[3] [5] [6] [7] [8]
CNSA is using Δ-DOR technique for Chang'e series lunar spacecraft tracking [9] [10]
ISRO is using Δ-DOR for the Mars Orbiter Mission (MOM).[11]
ESA is using Δ-DOR for the ExoMars Trace Gas Orbiter (TGO).[2]
References
edit- ^ a b Golombek, M. P.; et al. (15 July 2004). "Delta Differential One-way Ranging" (PDF). DSMS Telecommunications Link Design Handbook.
- ^ a b c Quasar to guide ESA's Mars landing. July 2016
- ^ a b c "Delta DOR". ESA. 28 September 2007.
- ^ "Delta Differential One-way Ranging Design Handbook" (PDF). NASA Deep Space Network. July 15, 2004. Archived from the original (PDF) on February 18, 2013.
- ^ Maddè Roberto; Morley Trevor; Abelló Ricard; et al. (November 2006). "Delta-DOR A New Technique for ESA's Deep Space Navigation" (PDF). ESA Bulletin 2006.
- ^ "The European ΔDOR System" (PDF). Luciano Iess, Dipartimento di Ingegneria Meccanica e Aerospaziale Sapienza Universita’ di Roma, Italy.
- ^ "Recommendation for Space Data System Practices. DELTA-DIFFERENTIAL ONE WAY RANGING (DELTA-DOR) OPERATIONSю RECOMMENDED PRACTICE. CCSDS 506.0-M-1. MAGENTA BOOK" (PDF). Consultative Committee for Space Data Systems (CCSDS). April 2011. Archived from the original (PDF) on 2016-03-04.
- ^ "ExoMars/TGO Operations". European Space Agency (ESA).
- ^ "The XF type correlator for Delta-DOR in deep space navigation". Chinese Academy of Sciences. 1 September 2014. Archived from the original on 3 March 2016.
- ^ Huang, Yong; Chang, Shengqi; Li, Peijia; Hu, Xiaogong; Wang, Guangli; Liu, Qinghui; Zheng, Weimin; Fan, Min (1 September 2014). "Orbit determination of Chang'E-3 and positioning of the lander and the rover". Chinese Science Bulletin. 59 (29–30): 3858–3867. Bibcode:2014ChSBu..59.3858H. doi:10.1007/s11434-014-0542-9.
- ^ ISRO, Indian Space Research Organisation (2015). Rao, P. V. Manoranjan (ed.). From Fishing Hamlet to Red Planet: India's Space Journey (EPUB). Noida, Uttar Pradesh, India: Harper Collins Publishers India. ISBN 9789351776895.
External links
edit- Deep Space Network (DSN)
- ESA Deep Space Network (Estrack)
- Indian Deep Space Network (IDSN) Archived 2016-08-28 at the Wayback Machine