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NGS GPS Calendar

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(@jim-frame)
Posts: 7277
Topic starter
 

My go-to GPS calendar is (well, has been) the one hosted by NGS.?ÿ But it didn't get updated to 2019, so I need to find another.?ÿ Any recommendations?

 
Posted : February 12, 2019 4:11 pm
(@jitterboogie)
Posts: 4279
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Can you just increment each of the days and continue the GPS week starting from Dec into Jan and then sequentially? ( not being cheeky)

 
Posted : February 12, 2019 4:18 pm
(@jim-frame)
Posts: 7277
Topic starter
 

Can you just increment each of the days and continue the GPS week starting from Dec into Jan and then sequentially? ( not being cheeky)

I *could* roll my own calendar, but with so many out there I'd rather let someone else do the work.?ÿ I was just wondering what other folks use.

Here are a few that I've found:

AGI GPS Calendar

gnsscalendar.com Calendar

leapsecond.com Calendar

?ÿ

 
Posted : February 12, 2019 4:25 pm
(@a-harris)
Posts: 8761
 

I have been using?ÿ

https://www.timeanddate.com/

and create a customized calendar with month, date and day number of the year.

 
Posted : February 12, 2019 6:58 pm
(@jim-frame)
Posts: 7277
Topic starter
 

I just got email from Bill Stone at NGS, who notified me that the calendar update apparently got overlooked but has now been accomplished.?ÿ Many thanks to NGS for getting the job done!

 
Posted : February 14, 2019 5:58 pm
(@geeoddmike)
Posts: 1556
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FWIW,

The NGS also provides some nice source code (in C) dealing with times and dates in GPS. See: https://www.ngs.noaa.gov/gps-toolbox/bwr-02.htm ?ÿAlso FORTRAN 77. A little more involved than merely incrementing.

Code was written by Dr. Benjamin W. Remondi. Took a course under him in the early 90ƒ??s. He was an excellent and inspiring instructor. I note this code is much easier to follow as ƒ??in the dayƒ? code had to be terse in order to run on slow processors with limited memory.?ÿ

Lots of other GPS-related code available here:?ÿ https://www.ngs.noaa.gov/gps-toolbox/exist.htm

?ÿ

 
Posted : February 14, 2019 9:24 pm
Wendell
(@wendell)
Posts: 5783
Admin
 

Being that I was barely dipping my toes into GPS stuff at the end of my surveying career, I never had the opportunity to deal with this kind of stuff. So I'm not very familiar with it. However, this thread has me thinking -- is this something that is delivered via some kind of feed or regularly updated website somewhere? Would this be a useful feature to have here at RPLS Today? If so, I'd be interested in discussing how to gather the data and present it properly if it's something I could automate.

Thoughts?

 
Posted : February 15, 2019 12:43 am
(@bill93)
Posts: 9834
 

Educate me.?ÿ Why do you need day of year??ÿ

My receiver automatically puts DOY in the filename, and I increment GPS week on a paper calendar in order to be able to override the erroneous date from the old receiver when converting to RINEX.

 
Posted : February 15, 2019 5:48 am
(@geeoddmike)
Posts: 1556
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As to Bill93ƒ??s question:

After asking the question why one needs the day of year, you follow with the reason. Many GPS receivers label their files with the DOY. I prefer the 8.3 file name convention: four-character station ID, three-digit DOY, one digit session ID, then two-digit year and finally file type (O,N,M, etc). More verbose file names are harder to keep track and require renaming for my use and archiving.

If asked for data from 13 February, I would have to convert that to DOY to find the files. Easy enough to calculate this early in the year, but what about 13 September? Writing or using a program for this task is straightforward. Some even find it fun.

Sites like the NGS UFCORS (ƒ??User Friendly CORSƒ?) were developed to facility data retrieval by doing the conversions itself. Not every data source is as accommodating.

?ÿ

 
Posted : February 15, 2019 9:24 am
(@jim-frame)
Posts: 7277
Topic starter
 

My receiver automatically puts DOY in the filename

My Javad receivers use a combination of point number and time-of-day to determine the file name.?ÿ I use the calendar to determine the day-of-year so that I download the right CORS observation files and precise orbit files.

 
Posted : February 15, 2019 9:24 am
(@a-harris)
Posts: 8761
 

My receiver also put the day of the year in the file name.

Knowing the day of the year in the office lets me quickly look for the files to grab and transfer into my GNSS software.

 
Posted : February 15, 2019 9:35 am
(@jim-frame)
Posts: 7277
Topic starter
 

Amending what I wrote above, for the precise orbit files I need the GPS week number and the day of the week.?ÿ The calendar provides both.

 
Posted : February 15, 2019 2:18 pm
(@shelby-h-griggs-pls)
Posts: 908
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I believe the NGS crew was on extended holiday at the 1st of the year and I suppose got overlooked, I was going to contact them, BUT it looks like Jim got it taken care of.

SHG

 
Posted : February 18, 2019 7:47 pm