forumchatter

I am looking for a utility that will show me a very good picture of the satellites overhead, their signal strength, etc.

I also would like this program to show me what satellites are WAAS satellites and whether or not I have a WAAS fix. Also if it could show me my estimated accuracy in a radius that would be great.

I use TomTom and iGuidance and also have the GPSInfo utility, but all of these aren't as detailed as I would like and none of them show WAAS and your estimated positional accuracy.

Free is always good but if a paid program is that much better then that's fine too..

Thanks

rlichtefeld

Originally Posted by forumchatter

I am looking for a utility that will show me a very good picture of the satellites overhead, their signal strength, etc. I also would like this program to show me what satellites are WAAS satellites and whether or not I have a WAAS fix. Also if it could show me my estimated accuracy in a radius that would be great. I use TomTom and iGuidance and also have the GPSInfo utility, but all of these aren't as detailed as I would like and none of them show WAAS and your estimated positional accuracy. Free is always good but if a paid program is that much better then that's fine too.. Thanks

Here's a free one:
http://www.usglobalsat.com/category.asp?catid=30
Download the GPSInfo program

Rob

forumchatter

yeah I have that one, I want something better with a more readable display and also something that shows if you have WAAS on or not, and if it could give you an estimated accuracy that would be good...

JakeRich

VisualGPSce may be what you are looking for. It shows satellites, strength and DOP. If you want a graphic representation of the fix, you'll need the laptop version VisualGPS. Not enough space on a PDA to do graphics of error circles. BTW, WAAS isn't GPS satellite related. The WAAS correction signal comes from geosynchronous satellites, not from the GPS satellites. The software in the receiver then creates a dummy GPS satellite from the geosynchronous data, if it does it at all.

forumchatter

okay well what number does the software assign to the WAAS satellite? when I look in the GPSInfo program for my Globalsat BC-337 CF SirfIII gps it shows the satellite numbers but I don't know which one(s) are the WAAS ones, and I have no way of telling if I am using a WAAS corrected fix or not..

I remember in the Garmin all-in-ones it would tell you if you were navigating under a WAAS corrected fix..

JakeRich

The following PRNs have been allocated to the WAAS system:
Geostationary/PRN/NMEA Satellite ID

AOR-W (moving)/122/35@
Anik/138/51*
POR/134/47@
PanAm /135/48*

Usually, if the software says you have a 3D fix, that's non-WAAS. 3D Enhanced is what some software uses to report a WAAS fix. It varies from package to package. If I might ask, why is this important to you? WAAS doesn't do much, really, for general navigation. Read GPS201 for my discussion of just that subject and why WAAS is normally not that important.

How WAAS works.

forumchatter

I ask because I use my pda for flying navigation as well and vertical accuracy via WAAS is very important for flying.

Those PRNs you listed, where do you see them? I dont' see any numbers that big, but I do see numbers in the 0-30+ range on each satellite signal strength bar... I'm assuming the numbers I am seeing are the NMEA Satellite ID numbers?

so is it safe to say if I see satellite 35,51,47, or 48 that has a lock then I am definately using a WAAS corrected fix? Do I only need one of those 4 listed satellites to get WAAS?

JakeRich

For aviation purposes you must have an FAA certified receiver. See this reference. It says, in part,

Quote:

To use GPS for navigation, the equipment must be certified in accordance with TSO-C129 and the installation must be done in accordance with AC 20-138 or AC 20-130A. TSO-C115a does not meet the requirements of TSO-C129.

To answer your question, the second set of digits, minus the special symbol, would be the satellite signal. It is NOT sufficient to be receiving and using the satellite data because one of the satellite signals says, basically, "Don't use me, my data is invalid." Whether or not you have a WAAS fix will be displayed by the approved software certified for flight purposes.

forumchatter

actually you only need an approved gps for IFR flying based on GPS approaches. I am only flying VFR so don't need an approved system, my use of it would only be for situation awareness, but the altitude info is definately still very important so that's why I want WAAS..