Talk:Dilution of precision (navigation)
![]() | This article is rated Start-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects: | |||||||||||||||||||||||||||
|
Untitled
editwhat the main the PDOP = 3.40, HDOP = 1.70, VDOP = 2.90
"Football field" ?
editDo you mean American or Soccer? Do you mean width or length?
American: 110m x 49m, Soccer 45m-90m x 90m-120m.
- All of these linear measurements are within the same order of magnitudes (approx >10m and < 1000m) and as a cultural reference to rough size of "bigness" any would do. (However the offending reference to "Football field" appears to have been removed.) --BrianFennell (talk) 20:21, 19 April 2009 (UTC)
Optimal DOP value
editThe table shows 0; I had understood it to be 1, so I looked at the lone reference, in hopes of learning more. The reference indicates 1 as optimal, but perhaps it's wrong. Are there any more references for this? 129.74.64.45 (talk) 01:42, 9 September 2008 (UTC)
Optimal value was set to 1 and now <1. Should not be still 1 as ideal? It's unclear what the range [0,1[ means... 2A01:E35:8BAB:7050:5039:E67F:8B81:CCBD (talk) 14:41, 20 October 2015 (UTC)
- By definition DOP continues to decrease as more rows are added to the design matrix. Early literature (from 1980s GPS) confused this because at the time the challenge was to select the best geometry given a limited number of channels. So as the number of satellites observed increases, the various DOP measures will continue to decrease. As the number of satellites tends to infinity, the corresponding matrix inverse will tend to zero.
- A DOP (H,V, G, etc) lower than 1 means the geometry is strong enough that the computer position error is expected to be better than a single range error. Kpgokeef (talk) 21:55, 9 February 2023 (UTC)
c in matrix calculation
editIf (x - xi)/Ri is meant to be a component of a unit vector (with length of 1 unit) it would seem then the time difference has already been converted to spacial distance for Ri. If so, why does c (speed of light) appear in the matrix math? I could see if Ri/c was meant to be meters/(meters/second) giving seconds in the final column (making it a time component), but having c standing out there all on it's own seems inconsistent. (Or am I missing something more basic or more esoteric here?)
Also it would be helpful is a more authortative document was referenced - GPS is a standard, and there must be a standard document for it defining (among other things) GDOP, HDOP, VDOP and PDOP as defined for use in GPS calculations. --BrianFennell (talk) 20:21, 19 April 2009 (UTC)
Excellent points. I just ran a GDOP calculation using c in the last column and the inverse is not usable due to the singularity of A'A. Using 1 instead of c in the final column is the method defined in Per Enge's book on GPS. -- Steven Waslander —Preceding unsigned comment added by 129.97.68.181 (talk) 15:48, 20 May 2009 (UTC)
Possible Articles to cite
editGPS GDOP metric - 2000 IEE Proceedings -
Dilution of Precision-Based Lunar Navigation Assessment for Dynamic Position Fixing
B.W. Parkinson (Ed) Global Positioning System: Theory and Applications, Vols I and II 1996, AIAA Press.
Matrix Inversion - Ask Dr Math
Underlining of math expression
editIn section "Computation of DOP values", the first math expression is underlined. Does this have some meaning, that I am not aware of, or is it there by mistake?
Rendering of italic math style z
editHave you noticed that the z letters (that are written in math style, and rendered) have lost their diagonal line? Now they look like the approximation symbol. I don't know if this could be fixed somehow, but it sure will confuse some people.
External links modified
editHello fellow Wikipedians,
I have just added archive links to one external link on Dilution of precision (GPS). Please take a moment to review my edit. If necessary, add {{cbignore}}
after the link to keep me from modifying it. Alternatively, you can add {{nobots|deny=InternetArchiveBot}}
to keep me off the page altogether. I made the following changes:
- Added archive https://web.archive.org/20081201060630/http://www.gmat.unsw.edu.au:80/snap/gps/gps_survey/chap1/142.htm to http://www.gmat.unsw.edu.au/snap/gps/gps_survey/chap1/142.htm
When you have finished reviewing my changes, please set the checked parameter below to true to let others know.
This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}}
(last update: 5 June 2024).
- If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
- If you found an error with any archives or the URLs themselves, you can fix them with this tool.
Cheers.—cyberbot IITalk to my owner:Online 01:27, 9 January 2016 (UTC)
External links modified (January 2018)
editHello fellow Wikipedians,
I have just modified 2 external links on Dilution of precision (navigation). Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
- Added archive https://web.archive.org/web/20140222000521/http://www.crowtracker.com/hdop-gps-position-errors/ to http://www.crowtracker.com/hdop-gps-position-errors/
- Added archive https://web.archive.org/web/20160310132600/http://edu-observatory.org/gps/gps_accuracy.html to http://www.edu-observatory.org/gps/gps_accuracy.html
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}}
(last update: 5 June 2024).
- If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
- If you found an error with any archives or the URLs themselves, you can fix them with this tool.
Cheers.—InternetArchiveBot (Report bug) 09:40, 23 January 2018 (UTC)
Duplication
editThere's significant overlap between the present article and section Error analysis for the Global Positioning System#Dillution of precision. fgnievinski (talk) 20:54, 13 April 2021 (UTC)
- I agree. Perhaps we could merge the content into this page, and replace that section with a summary and link to this page? TimSmit (talk) 01:13, 30 April 2021 (UTC)
- Redirected that section; no unique, relevant, referenced content to merge. Klbrain (talk) 10:07, 22 October 2022 (UTC)
- Maybe it would be better to make this article less GPS-specific, since the concept of DOP applies to many other systems. 92.180.50.162 (talk) 14:29, 25 July 2024 (UTC)
Interpretation
editThe section "Interpretation" is very specific to GPS, maybe specific to particular implementations of GPS. 92.180.50.162 (talk) 14:28, 25 July 2024 (UTC)