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None of the smartphones today have dedicated GPS chips in them, they only have a GPS capability that stems from byproduct features of the modem chips. Because of that, the GPS capability is very limited and poor, for example, you only receive one basic L1 signal, whereas if there was a GPS chip — it would also receive L2E as differential signal, or SBAS - a correction signal, thus drastically improving accuracy.

Question is would they ever do it, or would it be too big of a hit on the battery, some of the chips require pretty high voltage for some reason like 3V.

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closed as too broad by brhans, Maple, Dmitry Grigoryev, Finbarr, Lior Bilia Sep 14 '18 at 12:43

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    \$\begingroup\$ byproduct features of the modem chips - huh? \$\endgroup\$ – Eugene Sh. Sep 12 '18 at 20:25
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    \$\begingroup\$ @EugeneSh. Phone modem has super basic GPS feature added to it, no dedicated GPS chips \$\endgroup\$ – Jack Shephard Sep 12 '18 at 20:28
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    \$\begingroup\$ iPhone is not the only smartphone around. gsa.europa.eu/newsroom/news/… \$\endgroup\$ – Eugene Sh. Sep 12 '18 at 20:31
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    \$\begingroup\$ This is using a dedicated chip, which you claim it doesn't. As for iPhone, it is using one from the same family - BCM47734 as you can see here. \$\endgroup\$ – Eugene Sh. Sep 12 '18 at 20:36
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    \$\begingroup\$ If a GPS receiver functionality is embedded into some bigger chip (like modem) , it doesn't mean that it has less functionality than a "dedicated GPS". Every reputable LTE modem does have a GPS receiver embedded: "Additionally, XMM 7560 includes an integrated 4 mode GNSS with GPS, Galileo, GLONASS, and BeiDou positioning systems for worldwide satellite navigation support.", see intel.com/content/www/us/en/wireless-products/… \$\endgroup\$ – Ale..chenski Sep 12 '18 at 22:05
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None of the smartphones today have dedicated GPS chips in them, they only have a GPS capability that stems from byproduct features of the modem chips.

That's not true. GPS functionality in phones is done either with a dedicated chip, or with a dedicated GPS receiver within a System-On-Chip (which is effectively the same as having a dedicated chip).

Because of that, the GPS capability is very limited and poor

Huh, that would be news to me. In fact, I find GPS performance of phones astonishing, especially considering the fact that you can't just reserve the same size of antenna as in e.g. nautic navigation systems.

you only receive one basic L1 signal, whereas if there was a GPS chip — it would also receive L2E as differential signal, or SBAS - a correction signal, thus drastically improving accuracy.

As far as I can see, embedded GPS chips basically support all features of civilian GPS. Your claim has no backing.

My phone's GPS functionality has excellent differential GPS capabilities, for example.

Question is would they ever do it, or would it be too big of a hit on the battery, some of the chips require pretty high voltage for some reason like 3V.

Since they do, the answer is clear: Using the GPS circuitry / antenna does cost some battery, but every phone has GPS and thus it does work.

3V isn't per se a high voltage, even inside a smart phone – it's significantly below battery voltage, so easy and low-loss generatable from the battery.

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  • \$\begingroup\$ It really is amazing that GPS receivers can pick up signals lower than 140dBm \$\endgroup\$ – laptop2d Sep 13 '18 at 0:54
  • \$\begingroup\$ That, too, but that's just the beauty of high spreading factors/high processing gain in general :) \$\endgroup\$ – Marcus Müller Sep 13 '18 at 2:42

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