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betabeta

macrumors 6502a
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Jun 28, 2013
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GPS with A-GPS, GLONASS. With A-GPS line of sight is dropped from 3 to only 2 satellites, time to first fix is much better, generally has faster location acquisition with higher accuracy. Also better location acquisition indoors, takes less processing power and better battery usage.

Bluetooth 4.2, A2DP, LE. Uses less power, Up to two and half times faster, more secure, Apples iBeacons can’t be tracked, also has IP connectivity for sensors, light bulbs and other sensors.

I really like this, especially the GPS.

This really sounds like a great upgrade, going forward I think the watch will be more interesting like the early iPhone upgrades. I’m not really interested in what they added to phone, it’s pretty much peaked at the the 6plus for me and the new iPhone features are not really making it more useful to me.

But The :apple:watch is the device to watch:D
 
Isn't it the same gps as the series 2?

It is, The series 3 has an identical Heart Rate sensor as well. That is mainly the reason im not updating to the Series 3, Way too many similarities to my SS Series 2. The built in barometer in the Series 3 is a big deal and a fantastic addition but i'll be taking a 300$ loss if i was to sell my Series 2 SS and getting the 650$+ Series 3 SS, i dont think that the barometer all by itself justifies me doing so anyways, ill be getting the Series 4 next year. i'm not sure where the OP got his information that the series 3 has different GPS Components than the Series 2.
 
GPS with A-GPS, GLONASS. With A-GPS line of sight is dropped from 3 to only 2 satellites, time to first fix is much better, generally has faster location acquisition with higher accuracy. Also better location acquisition indoors, takes less processing power and better battery usage.
Please explain. I'm curious how you think A-GPS works as the above doesn't quite make sense with my understanding (which could be wrong or out of date).

Also, as above, could you please reference where the S3 improvement info came from?
 
It is, The series 3 has an identical Heart Rate sensor as well. That is mainly the reason im not updating to the Series 3, Way too many similarities to my SS Series 2. The built in barometer in the Series 3 is a big deal and a fantastic addition but i'll be taking a 300$ loss if i was to sell my Series 2 SS and getting the 650$+ Series 3 SS, i dont think that the barometer all by itself justifies me doing so anyways, ill be getting the Series 4 next year. i'm not sure where the OP got his information that the series 3 has different GPS Components than the Series 2.

A lot of ways, I think the Series 2 Apple Watch was a significant improvement over the first generation, but I question how much improvement the Series 3 is over the Series 2. Mainly LTE is the biggest selling point with the Series 3.
 
A lot of ways, I think the Series 2 Apple Watch was a significant improvement over the first generation, but I question how much improvement the Series 3 is over the Series 2. Mainly LTE is the biggest selling point with the Series 3.

Its an excellent update regardless and i personally dont even care about the LTE Feature, the built in barometer is a big deal i just cant justify selling my SS Series 2 for peanuts and then spend another 350-400$ on top of it to buy the SS Series 3, there just isn't much of a difference. Same design. Same HR sensor too which was disappointing to say the least.
 
Its an excellent update regardless and i personally dont even care about the LTE Feature, the built in barometer is a big deal i just cant justify selling my SS Series 2 for peanuts and then spend another 350-400$ on top of it to buy the SS Series 3, there just isn't much of a difference. Same design. Same HR sensor too which was disappointing to say the least.

When I see a redesign, more watch faces, a larger watch display, that would be worth upgrading to in my opinion.
 
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Please explain. I'm curious how you think A-GPS works as the above doesn't quite make sense with my understanding (which could be wrong or out of date).

Also, as above, could you please reference where the S3 improvement info came from?

A-GPS is Assisted GPS. Basically it uses cell phone towers and triangulation to "assist" the GPS signal. Thats why you can get a pretty good location in buildings on the iPhone, where GPS otherwise would completely fail. It was only "added" because of the addition of cellular.
 
Please explain. I'm curious how you think A-GPS works as the above doesn't quite make sense with my understanding (which could be wrong or out of date).

Also, as above, could you please reference where the S3 improvement info came from?

A-GPS assists/helps by collecting data from nearby cell towers,
GPS needs to connect to satellite for orbit and clock data before it knows its location which can take 20 seconds or much longer before it can acquire a signal...this depends on your location, areas in cities with tall buildings can take longer, out in the open is much faster.

With assisted GPS, this process is much faster, as it uses cell towers to get the information about the location of satellites saving time and thus processing power and of course battery. iPhones use A-GPS.

I found this information a while ago, should be known for sure next week of course. the Apple site does not mention A-GPS, but it doesn’t mention a few things that series 3 has, mostly technical acronyms people wouldn’t care about. Of course something could have changed, but the reason it wasn’t in series 2 is the lack of cellular of course, it would have been useless.

Series 3 is shaping up to be a really impressive upgrade, these minor improvements don’t mean anything to most people but work together to make things work more efficient.
 
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A-GPS is Assisted GPS. Basically it uses cell phone towers and triangulation to "assist" the GPS signal.


No. Triangulation went away when phones got GPS chips. https://en.wikipedia.org/wiki/Assisted_GPS

Thats why you can get a pretty good location in buildings on the iPhone, where GPS otherwise would completely fail. It was only "added" because of the addition of cellular.

Getting location inside buildings occurs with the supplement of wifi location mapping. See https://en.wikipedia.org/wiki/Wi-Fi_positioning_system


A-GPS assists/helps by collecting data from nearby cell towers,
GPS needs to connect to satellite for orbit and clock data before it knows its location which can take 20 seconds or much longer before it can acquire a signal...this depends on your location, areas in cities with tall buildings can take longer, out in the open is much faster.

With assisted GPS, this process is much faster, as it uses cell towers to get the information about the location of satellites saving time and thus processing power and of course battery. iPhones use A-GPS.

Pretty close. A-GPS essentially aids in time to first fix by having the cell towers transmitting the satellite ephemeris to the device. This is the table that says which satellite is where. Otherwise a device may have to collect the ephemeris as it is transmitted (more slowly) by the satellites themselves.

Many current sports watches work with their connected devices to preload the current ephemeris. I suspect that is done with the AW2. It's typically taken the same few seconds to acquire a GPS fix as my FR235 which uses a cached ephemeris that is updated via its connection to your phone.

So while technically the additional of cellular capability does provide the possibility of assisted GPS ephemeris loading, I don't expect it'll make a discernible difference vs. the AW2 in acquisition or accuracy.
 
So while technically the additional of cellular capability does provide the possibility of assisted GPS ephemeris loading, I don't expect it'll make a discernible difference vs. the AW2 in acquisition or accuracy.

Well it will make a difference when you leave the iPhone at home, which is kinda the point of having LTE in the Watch in the first place, isn't it?
 
Well it will make a difference when you leave the iPhone at home, which is kinda the point of having LTE in the Watch in the first place, isn't it?

How do you know it will make a difference?

When I run with my AW2, by the time I start the GPS I am far away from my phone. It gets a fix in a few seconds. I've also stopped and restarted an activity while a couple miles away. Same short first time to fix.

With my FR235 the ephemeris preload cache is good for several days. I'd expect the Apple Watch to be similar. Do you plan to be away from your phone that long?

In comparison I've owned an FR610 which doesn't preload an ephemeris. If it'd been off for several days it could take a couple minutes or more to get a first fix. Later times, if within a couple days, were quick as the ephemeris data was still good -- and it'd get the fresh updates from the satellites during the run.

I guess what I'm saying is I have experience with the different setups and don't see that there will be much difference in AW2 vs AW3 for GPS first fix outside of some rare exception circumstance.
 
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Don't forget the move to a dual-core processor. I haven't used a S2 model so don't know how the speed was, but I suspect this will be a big deal especially with 3rd party apps.
 
Yes, a speed increase is a reason I've ordered. I think the # of cores is the same though.
 
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Don't forget the move to a dual-core processor. I haven't used a S2 model so don't know how the speed was, but I suspect this will be a big deal especially with 3rd party apps.

The series 2 also has a dual core processor.
 
How do you know it will make a difference?

When I run with my AW2, by the time I start the GPS I am far away from my phone. It gets a fix in a few seconds. I've also stopped and restarted an activity while a couple miles away. Same short first time to fix.

With my FR235 the ephemeris preload cache is good for several days. I'd expect the Apple Watch to be similar. Do you plan to be away from your phone that long?

In comparison I've owned an FR610 which doesn't preload an ephemeris. If it'd been off for several days it could take a couple minutes or more to get a first fix. Later times, if within a couple days, were quick as the ephemeris data was still good -- and it'd get the fresh updates from the satellites during the run.

I guess what I'm saying is I have experience with the different setups and don't see that there will be much difference in AW2 vs AW3 for GPS first fix outside of some rare exception circumstance.

I don't know it'll make a difference, I just assumed it was logical that the LTE on the Watch will help with the A- part of A-GPS when the iPhone is not around.
 
Ah, weird that they noted that like it was new in the keynote. Is the '70%' faster relative to the S2?

Yeah the dual core processor in the series 3 is faster for sure but the series 2 also has a dual core processor.
 
I don't know it'll make a difference, I just assumed it was logical that the LTE on the Watch will help with the A- part of A-GPS when the iPhone is not around.
If the watch weren't caching the ephemeris it definitely would help with time to first fix. While I can't point to anything that definitively says the AW2 does that, its behavior in comparison to Garmin sports watches with and without ephemeris caching leads me to believe it does so.
 
No. Triangulation went away when phones got GPS chips. https://en.wikipedia.org/wiki/Assisted_GPS



Getting location inside buildings occurs with the supplement of wifi location mapping. See https://en.wikipedia.org/wiki/Wi-Fi_positioning_system




Pretty close. A-GPS essentially aids in time to first fix by having the cell towers transmitting the satellite ephemeris to the device. This is the table that says which satellite is where. Otherwise a device may have to collect the ephemeris as it is transmitted (more slowly) by the satellites themselves.

Many current sports watches work with their connected devices to preload the current ephemeris. I suspect that is done with the AW2. It's typically taken the same few seconds to acquire a GPS fix as my FR235 which uses a cached ephemeris that is updated via its connection to your phone.

So while technically the additional of cellular capability does provide the possibility of assisted GPS ephemeris loading, I don't expect it'll make a discernible difference vs. the AW2 in acquisition or accuracy.

I bet you are fun at parties.
 
Please explain. I'm curious how you think A-GPS works as the above doesn't quite make sense with my understanding (which could be wrong or out of date).

Also, as above, could you please reference where the S3 improvement info came from?
A-GPS means Assisted GPS which means the cell tower locations of the LTE signal are known in advance on a map, and can be used to confirm position via triangulation before the GPS signal lock is established. Phones have been doing it since the iPhone 4 days.
If not known in advance then the phone builds a map over time based on GPS locations when it is fired up and distance based calculation. There was a big scandal about the iPhone 4 storing this cell tower map in iTunes backups (the outrage crowd was in full force even back then).

It is the reason you get a 1-block circle of approximate position in the Maps app for a few seconds before the exact location fires up. It is also how the original iPhone could get a location without GPS. The cell tower triangulation is just not that exact due to signal reflections and interference.
 
A-GPS means Assisted GPS which means the cell tower locations of the LTE signal are known in advance on a map, and can be used to confirm position via triangulation before the GPS signal lock is established.
Reference please? That is contrary to everything I've seen over several years of being interested in the topic. I'd love to know more about the topic.
http://www.gpsworld.com/wp-content/uploads/2012/09/gpsworld_Innovation_0302.pdf


It is the reason you get a 1-block circle of approximate position in the Maps app for a few seconds before the exact location fires up. It is also how the original iPhone could get a location without GPS.

I suspect you may be conflating aGPS with Wifi-positioning a la Skyhook Wireless's products and/or using the nearest cell tower location as a first approximation. https://en.wikipedia.org/wiki/Skyhook_Wireless
http://www.poi-factory.com/node/33259
https://en.wikipedia.org/wiki/Mobile_phone_tracking


In any event, it really doesn't matter. My AW2 gets a solid position fix in a matter of seconds, based on viewing the starting points of many runs. At the time of starting the GPS my phone has been in a metal locker, about 150 away, through several concrete walls. No connection to the watch. Any improvement brought by the cellular capability of the AW3 will be minor IMHO outside of exceptional circumstances..
 
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It is, The series 3 has an identical Heart Rate sensor as well. That is mainly the reason im not updating to the Series 3, Way too many similarities to my SS Series 2. The built in barometer in the Series 3 is a big deal and a fantastic addition but i'll be taking a 300$ loss if i was to sell my Series 2 SS and getting the 650$+ Series 3 SS, i dont think that the barometer all by itself justifies me doing so anyways, ill be getting the Series 4 next year. i'm not sure where the OP got his information that the series 3 has different GPS Components than the Series 2.

Apparently, the Series 2 has a built-in barometer as well...just not activated.
 
Apparently, the Series 2 has a built-in barometer as well...just not activated.

Yeah that has been known for many months, doubt it will be activated as that will nullify one of the main selling points of the Series 3 which is the barometer which measures elevation parameters, Floors climbed which are vital for a complete fitness tracking profile. If you carry your phone with you all times during the day then the lack of a barometer in the series 2 is not that big of a deal as the iPhone measures it instead, however I walk up and down stairs multiple times during the day and I don’t have the iPhone on me at all times and the Apple Watch simply doesn’t count these climbed floors as it has no built in barometer
 
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