Stationary GPS unit shows movement...

Discussion in 'General GPS Discussion' started by rflegel, May 1, 2015.

  1. rflegel

    rflegel

    Joined:
    May 1, 2015
    Messages:
    1
    Likes Received:
    0
    Location:
    Olympic Peninsula, Washington State, USA
    I'm new to GPS and am using an older unit, a Magellan CrossoverGPS. While charging the battery at home with the GPS sitting on a table, the stationary GPS unit shows movement of 150' in about 1 ¼ hours.

    I am guessing this might be due to satellite movement, but am not sure. This seems like a lot of movement in such a short time.

    Is this consistent with what other users have noticed?

    Thanks!
     
    rflegel, May 1, 2015
    #1
    1. Advertisements

  2. rflegel

    Nuvi-Nebie Moderator

    Joined:
    Aug 16, 2015
    Messages:
    1,939
    Likes Received:
    159
    Location:
    UK
    All GPS satellites, apart from the one or two geostationary Egnos / WAAS satellites, are constantly moving across the sky, GPS works by measuring the varying distances from at least 3 satellites to the GPS receiver, the satellite's movement is not the problem, Theoretically your GPS should give you a single stationary point where ever the satellites are, however inaccuracies are introduced by the GPS's clock and also by the satellites not being in the best location (the further apart they are the better). The satellites carry very accurate atomic clocks, however your GPS does not, so it is quite normal for GPSs to get the time (and it's position) slightly wrong, this shows up as a moving location when the GPS is actually stationary. All GPSs, both new and old do this to some degree, although newer GPSs have the advantage of being more sensitive, being able to use not only GPS but also Egnos / WAAS and Glonass satellites etc. all of which cuts down errors. Some GPSs also perform averaging where many readings are taken over a long period and summed into a single more accurate stationary location
     
    Nuvi-Nebie, Aug 21, 2015
    #2
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.