[LEAPSECS] Recording GPS leap-second

[Richard B. Langley]

Having the sampled live RF for playback into an arbitrary GPS receiver  
is a good idea. See my latest GPS World Innovation column for a cost- 
effective approach using a USRP:
http://www.nxtbook.com/nxtbooks/questex/gps0512/

Also, many GPS simulators already have the capability of simulating  
the leap second for testing receivers ahead of the actual event.

There are many monitoring network GPS (and GPS/GLONASS/whatever)  
receivers of different makes/models/vintages operating continuously,  
some with data rates as high as 1 Hz or more, that can be checked  
after the fact for correct operation through the leap second.

A u-blox GPS receiver handled the leap second correctly, as evidenced  
by the NMEA 0183 GPZDA message, during the leap second event of 31  
December 2005:
http://www.mail-archive.com/leapsecs@rom.usno.navy.mil/msg00903.html

-- Richard Langley

On 7-May-12, at 4:23 PM, Poul-Henning Kamp wrote:


> In message <20120507191612.0E6AD73084 at walton.maths.tcd.ie>, David  

> Malone writes

> :

>>> Are anybody are working on making a spectrum recording of GPS  

>>> signals

>>> around the leapsecond, for use as test-stimuli for testing leap- 

>>> second

>>> handling ?

>>

>>> I suspect that a USRP should be able to do the job ?

>>

>> If you have the right front end, I guess it would be possible. Would

>> you just capture a slice around the L1 and L2 frequencies, or try

>> to capture a big chunk of the band? (I guess a few MHz around L1

>> would probably be enough to be useful.) I have access to a spectrum

>> analyser that works in the band, but its memory is probably too

>

> My idea would be at least two hours of L1, suitable to playback

> later on...

>

> -- 

> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20

> phk at FreeBSD.ORG         | TCP/IP since RFC 956

> FreeBSD committer       | BSD since 4.3-tahoe

> Never attribute to malice what can adequately be explained by  

> incompetence.

> _______________________________________________

> LEAPSECS mailing list

> LEAPSECS at leapsecond.com

> http://six.pairlist.net/mailman/listinfo/leapsecs


-----------------------------------------------------------------------------

| Richard B. Langley                            E-mail:  

lang at unb.ca         |

| Geodetic Research Laboratory                  Web: http://www.unb.ca/GGE/ 

  |

| Dept. of Geodesy and Geomatics Engineering    Phone:    +1 506  

453-5142   |

| University of New Brunswick                   Fax:      +1 506  

453-4943   |

| Fredericton, N.B., Canada  E3B  

5A3                                        |

|        Fredericton?  Where's that?  See: http:// 

www.fredericton.ca/       |
-----------------------------------------------------------------------------