Welcome, Guest. Please login or register.

Login with username, password and session length
Forums Search:  


Author Topic: WAAS -- any reason not to have engaged?  (Read 1889 times)

LeslieG

  • Newbie
  • *
  • Posts: 1
  • Karma: 0
    • View Profile
WAAS -- any reason not to have engaged?
« on: September 15, 2009, 01:43:02 PM »
I live in New York, so assume WAAS should add to the accuracy. Is there a reason to disengage WAAS ever?

leszekp

  • Mapper
  • ***
  • Posts: 103
  • Karma: 8
    • View Profile
Re: WAAS -- any reason not to have engaged?
« Reply #1 on: September 15, 2009, 09:34:04 PM »
Theoretically, there's one set of circumstances where having WAAS turned on might degrade accuracy. If you have a 12-channel unit, and there are 12 or more GPS satellites visible, having WAAS enabled would "crowd out" one of the available slots for GPS satellites. If the missing satellite was in a key area for the best geometry, you could in theory get slightly more accurate positions by turning WAAS off to free up that one satellite spot.

In practice, though, this is so incredibly unlikely to happen that for accuracy, you're always better off having WAAS turned on. It will also reduce battery life slightly, but not by very much.