Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Is the iPhone 3G WAAS enabled?
- Thread starter Nerd.Alert.com
- Start date
- Sort by reaction score
Nothing in the GPS chip docs to indicate that capability.
Click on the PMB-2525 .pdf link at this page to see the chip brochure
Click on the PMB-2525 .pdf link at this page to see the chip brochure
It's been two years now. Anybody have any insight on this question by OP?
I am pondering purchasing a Humminbird sonar for fishing, and trying to decide to get a GPS or non-GPS unit. The Humminbirds use 50 channel WAAS GPS receiver. Supposedly it allows pinpoint location to within ten feet or so.
I know the iPhone GPS has been very accurate for me. I have Navionics loaded on my iPhone which I use as a GPS when out fishing on the lakes. It would be redundant to get the same functionality on the Humminbird that I have with my iPhone. Hence the decision.
So main question, is the iPhone WAAS GPS or not?
I didn't realize anyone other than pilots even cared about WAAS. We need it in order to use GPS in a precision approach to land, but I don't know if it is worth paying extra for it in any ground-based application. It does use battery faster than GPS without, so the odds are Apple didn't add it into the iPhone. They count on their WiFi assist and cell tower triangulation to do their differential GPS. So if you want the added accuracy of WAAS you will probably have to pay the extra for it on your sonar. If your sonar is tied to the boat's electrical system the extra battery drain issue goes away, too.
Thanks for your response jzuena. I'm leaning now towards getting the gps sonar. At the very least I will have it mounted so it is visible when motoring to fishing locations. There may be times when I don't want to constantly whip out my iPhone for use as a gps (i.e. rain, waves). Hate to see it go overboard when blindsided by a wave. Also, better not to have too many things tied into one device. Cause if the battery on the iPhone dies, then I am SOL when needed a phone. The detractions of having a multi-use device! I will have the GPS/Sonar hooked to onboard battery so that is not an issue.
WAAS use in handheld devices
As someone who does software and algorithmic development for the WAAS system, I have to say that WAAS would be an interesting thing to add to smart phones such as the IPhone and I currently do not know of any phone that currently uses it.
The claim about lower battery life because you would have to listen for a while seems like a somewhat valid concern, but overall I would call it pretty much bogus. The WAAS system uses the same delivery method as GPS satelittes and sends a specially signal that marks it as being different from the GPS system. This signal provides only 250 BITS (thats 250 ones and zeroes, every second to WAAS enabled recievers. This basically would be an encoded message that tells you how the satellites in space need correct and ALSO provides a safety margin. So it does make GPS somewhat more accurate.
GPS receivers normally take a few seconds to get data from all the satellites on their positions. We often call this the almanac, smart phones found out that rather then spending more battery life on leaving the GPS receiver on for an extended period it was far quicker if this was sent across the cellphone network (which has MUCH higher bandwidth) to speed up the process. This same method could be provided for WAAS as well, but it would take up slightly more bandwidth to do so. Keep in mind the amount of data this would be is about the same as a word in a text message.
The case against WAAS in this situation is pretty grim however, as the networks would have to be able to provide this information across their network as well as the GPS data they already provide. This may not mean much to us, but the networks are very stingy about more data that is provided across their already stressed networks at times, and any additional code that might have to be added to the already complex (to them) GPS solutions.
In short, I don't see it being used anytime soon.
As someone who does software and algorithmic development for the WAAS system, I have to say that WAAS would be an interesting thing to add to smart phones such as the IPhone and I currently do not know of any phone that currently uses it.
The claim about lower battery life because you would have to listen for a while seems like a somewhat valid concern, but overall I would call it pretty much bogus. The WAAS system uses the same delivery method as GPS satelittes and sends a specially signal that marks it as being different from the GPS system. This signal provides only 250 BITS (thats 250 ones and zeroes, every second to WAAS enabled recievers. This basically would be an encoded message that tells you how the satellites in space need correct and ALSO provides a safety margin. So it does make GPS somewhat more accurate.
GPS receivers normally take a few seconds to get data from all the satellites on their positions. We often call this the almanac, smart phones found out that rather then spending more battery life on leaving the GPS receiver on for an extended period it was far quicker if this was sent across the cellphone network (which has MUCH higher bandwidth) to speed up the process. This same method could be provided for WAAS as well, but it would take up slightly more bandwidth to do so. Keep in mind the amount of data this would be is about the same as a word in a text message.
The case against WAAS in this situation is pretty grim however, as the networks would have to be able to provide this information across their network as well as the GPS data they already provide. This may not mean much to us, but the networks are very stingy about more data that is provided across their already stressed networks at times, and any additional code that might have to be added to the already complex (to them) GPS solutions.
In short, I don't see it being used anytime soon.