A question to the hive: In-car Navigations systems and how they differ from phone Nav Apps

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WeyounDS9

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Maybe someone can school me, if this assumption of mine is correct or not:

Barring an On-star kind of system, do in-car navigation systems just passively receive sattelite signals and then navigate your display based on an internal database?
Or do they also actively emit a signature and "ping" cell phone towers in any way?

In my experience phone Nav apps can stop workign as soon as u are away from cell towers if you drive through the boonies.
But my garmin still works.
I guess the same question apllies to a Garmin too?
Is it passive only or does it emit a signature?

I also remember an older Infiniti of m,ine needed a CD with new data every so often, so it does not seem to connect anywhere and update on its own like a phone app ( which is not a bad thing)
 
Both receive and calculate the location based on gps signals. Both rely on a map, which it places your “dot” upon. Your car and your garmin have the entire map stored in memory, which is why they need occasional updates. The phone relies on cel signal to pull down the current map for the area, or foe the planned route.

no transmission is done back to the gps constellation to do this.

some phone apps will transmit telematics, road hazards and other data back to collect and show traffic information such as backups.

gps is rather interesting. Each satellite is simply transmitting its time, on the same frequency. The gps receiver “sees” each satellite on different frequencies due to Doppler shift relative to its location, and the time delay it takes for each time announcement from each satellite to reach it. Sat-to-ground transmission delays are measurable in understandable numbers!
 
palmerwmd said:
M

In my experience phone Nav apps can stop workign as soon as u are away from cell towers if you drive through the boonies.
But my garmin still works.
I guess the same question apllies to a Garmin too?
Is it passive only or does it emit a signature?

I also remember an older Infiniti of m,ine needed a CD with new data every so often, so it does not seem to connect anywhere and update on its own like a phone app ( which is not a bad thing)
Click to expand...

So the phone apps are using current data.. you can also download offline data for use with no phone signal.
Most car navs well.... the "tomtom" based ones in my 22 forester have the speed limit wrong aprox 50% of the time and appear to be years old already..

What do you mean by "emits" a signal?
they both use gps for location..(passive reception) and use data either stored onboard or by getting data from phone towers.(uses phone signal)
Some car based ones will use siriusxm for traffic and weather data..
 
I think built in navigation is outdated, it generally doesn't receive map updates or live traffic info. With wireless Apple Carplay and Android Auto, you can use Waze that will route you based on traffic and alert you to accidents, speed traps and red light cameras.
 
Thanks to all that answered. :)

I am interested to see that my assumption is correct, that a in-car Nav will allow me to navigate solely by passive reception of signal without pinging cell phone powers or anything else.

This means it will still work in a general power outage that knocked out towers.

Also I like the idea that if I dont carry my phone i cannot be tracked via my Nav application.
One small victory against the surveillance state.
 
palmerwmd said:
Maybe someone can school me, if this assumption of mine is correct or not:

Barring an On-star kind of system, do in-car navigation systems just passively receive sattelite signals and then navigate your display based on an internal database?
Or do they also actively emit a signature and "ping" cell phone towers in any way?

In my experience phone Nav apps can stop workign as soon as u are away from cell towers if you drive through the boonies.
But my garmin still works.
I guess the same question apllies to a Garmin too?
Is it passive only or does it emit a signature?

I also remember an older Infiniti of m,ine needed a CD with new data every so often, so it does not seem to connect anywhere and update on its own like a phone app ( which is not a bad thing)
Click to expand...
Phone apps, like Apple Maps, Google Maps*, Waze, etc. uses cellular data to actively display the location based on GPS signals. So, when you lose cellular data reception, that map data goes "blank" on the screen

*Google Maps have the ability to download "Offline Maps" when you plan on going into areas of no cellular signal.

Garmins have the map data saved onto the device, so it needs a GPS signal only.

Car factory navigation has the map data saved onto the device, so it needs a GPS signal only.
 
The "Navigation System" on my 2018 Toyota is useless without a cell phone plugged into it. Not only that, but the phone must have the Scout app loaded into it in order to work. Then you have to plug the phone into the USB port on the dash. (It won't work wireless).

All the car basically does is put the screen of the phone up on the dash monitor. It's the absolute worse system I've ever seen, and never use it because it's such a PITA. Hard to believe a company with the size and reputation of Toyota, would actually market such a piece of crap. It's almost as if they designed it as an afterthought.

Who is going to go through all that nonsense every time they get into the car to go somewhere? This in contrast to the U-Connect system in my Jeep that boots up on the display exactly where I'm at every time it starts. No driver input required.

Plus it has pages at the touch that will tell you where the cheapest gas is, the best pizza in town, how to get there, and all of that other nonsense most will either never use, or else get into an accident trying to.
 
billt460 said:
The "Navigation System" on my 2018 Toyota is useless without a cell phone plugged into it. Not only that, but the phone must have the Scout app loaded into it in order to work. Then you have to plug the phone into the USB port on the dash. (It won't work wireless).

All the car basically does is put the screen of the phone up on the dash monitor. It's the absolute worse system I've ever seen, and never use it because it's such a PITA. Hard to believe a company with the size and reputation of Toyota, would actually market such a piece of crap. It's almost as if they designed it as an afterthought.

Who is going to go through all that nonsense every time they get into the car to go somewhere? This in contrast to the U-Connect system in my Jeep that boots up on the display exactly where I'm at every time it starts. No driver input required.

Plus it has pages at the touch that will tell you where the cheapest gas is, the best pizza in town, how to get there, and all of that other nonsense most will either never use, or else get into an accident trying to.
Click to expand...
Toyota has two/three different navigation systems - the one you have needs the Toyota Entune app on a smartphone. It uses Scout maps. The other uses Denso software/maps and is called “premium navigation” on the Toyota side. It’s standard fare on the Lexus side. The third one only applies with CarPlay or Android Auto using that mapping. They were very late to the game.

In-car navigation isn’t worth it - but unlike depending on Apple/Google Maps or Waze via CarPlay or Android Auto, the built-in system has a gyroscope or will use the vehicle speed sensor signal via the ABS ECU for dead reckoning and the car’s GPS antenna while it must see the open sky is much more sensitive than the one on your phone. Your phone’s mapping app does have the benefit of aGPS. In-car systems are expensive to update. Toyota/Lexus wants $180-250 + .5-1hr of labor if your system has any kind of DRM needing the service department to request a auth code and loading the system.

Some aftermarket decks have an external GPS antenna.
 
meep said:
Both receive and calculate the location based on gps signals. Both rely on a map, which it places your “dot” upon. Your car and your garmin have the entire map stored in memory, which is why they need occasional updates. The phone relies on cel signal to pull down the current map for the area, or foe the planned route.

no transmission is done back to the gps constellation to do this.

some phone apps will transmit telematics, road hazards and other data back to collect and show traffic information such as backups.

gps is rather interesting. Each satellite is simply transmitting its time, on the same frequency. The gps receiver “sees” each satellite on different frequencies due to Doppler shift relative to its location, and the time delay it takes for each time announcement from each satellite to reach it. Sat-to-ground transmission delays are measurable in understandable numbers!
Click to expand...

Also, some in car navs will use the vehicle speed and steering input to determine where you are going when there's no gps signal, like in a tunnel complex. Phone apps are usually lost, and the standalone sat navs kinda assume a constant speed and that you make the right turns..
 
When I had a Garmin I could download open source maps that were only weeks old, formatted in 2, 4, or 8 GB files. Just had to copy them to SD card with a special name then the Garmin would update itself, and without me paying Garmin, LOL.
 
I remember my first Gadmin portable nav units back in the days before smart phones. Man, they were a game-changer!

One other difference I’ve noticed, but never looked into. It seems that a smart phones can pickup gps signals faster, at least from what I’ve experienced. I believe this is because even with the GPS location turned off, cell towers can be used to roughly triangulate your position. It seems as if this helps determine which satellites to look for, whereas a dumb GPS may not know where to look. Is there any truth to this?

Back to my first Garmins: out of the box (or factory reset) and after I traveled by plane to somewhere far away it would take forever to find enough satellites to begin navigating. My earlier Garmins even had a screen showing which satellites it had locked onto.
 
palmerwmd said:
Thanks to all that answered. :)

I am interested to see that my assumption is correct, that a in-car Nav will allow me to navigate solely by passive reception of signal without pinging cell phone powers or anything else.

This means it will still work in a general power outage that knocked out towers.

Also I like the idea that if I dont carry my phone i cannot be tracked via my Nav application.
One small victory against the surveillance state.
Click to expand...
Until you get to where you are going, then they will track everything you do so unless you pay with cash and have no cell phone. It is getting harder t pay with cash.
 
tmorris1 said:
Until you get to where you are going, then they will track everything you do so unless you pay with cash and have no cell phone. It is getting harder t pay with cash.
Click to expand...
It's all about surviving by the inches, as they used to say in the Infantry when you use microcover like a curb.
Is it good cover? No, but it's something.

A multiple of prudent, even if imperfect steps, adds up. :)
 
tmorris1 said:
It is getting harder t pay with cash.
Click to expand...
Yes it is.

I believe this is also at the root of the enthusiasm our political class has for electric cars.
With an internal combustion engine I can drive coast to coast on cash only, in 3 days.

This level of mobility will disappear when we all drive only electric cars both due to the recharge issue.
On E cars it takes generally 45 minutes for a 80% charge that restores maybe some 160 miles of range vs 5 minutes for a full top off that restores 500 mile range) and.... charging station all run By electronic paymnet and/or tracking as your car "talks" to the charger.
IF you dont have to wait for a spot at the charger which will be a thing of the past when we all do it.

Reduced mobility for the Hoi Polloi and better tracking.. a win-win for the political class.
 
PS: you guys are really selling me on the in -car Navs as it turns out my semi-educated guesses are validated by the qualified input on this forum.
 
gathermewool said:
I remember my first Gadmin portable nav units back in the days before smart phones. Man, they were a game-changer!

One other difference I’ve noticed, but never looked into. It seems that a smart phones can pickup gps signals faster, at least from what I’ve experienced. I believe this is because even with the GPS location turned off, cell towers can be used to roughly triangulate your position. It seems as if this helps determine which satellites to look for, whereas a dumb GPS may not know where to look. Is there any truth to this?

Back to my first Garmins: out of the box (or factory reset) and after I traveled by plane to somewhere far away it would take forever to find enough satellites to begin navigating. My earlier Garmins even had a screen showing which satellites it had locked onto.
Click to expand...
Verizon and Sprint introduced aGPS first - more for revenue reasons(the BlackBerry Pearl/Bold/88xx series for CDMA as well as their Windows Mobile/Palm Treos came with a full GPS receiver in their Qualcomm modems but was crippled in software to force people to use VZ Navigator/Sprint Maps - ditto with the Motorola RAZR and LG Chocolate/EnV to force you to buy an app off GetItNow) - but the technical reasoning for quicker GPS fix was solid. Back then, even the SiRF(now Qualcomm) GPS receivers had slow fix. Now, aGPS augmented by wifi/Bluetooth LE and UWB allows for almost instant fix even indoors.

Garmin licensed their software to Mopar, Honda and JVCKenwood. The Kenwood Excelon DVD/digital media with Garmin navigation decks are really nice, but really expensive and kinda pointless since they also include CarPlay/Android Auto - but the Garmin UX is very intuitive. Pioneer is using some eGo navigation system that isn’t great.
 
palmerwmd said:
Also I like the idea that if I dont carry my phone i cannot be tracked via my Nav application.
One small victory against the surveillance state.
Click to expand...
Well - depending on how "modern" your car is, it will phone home.

Last time I got my car repaired, I got a loaner from the repair shop.
I was quite shocked to learn, that they could not only track my position from their computer,
they also know the speed, how hard I brake/accelerate, mileage, if I fill her up etc.
And all that was not with some special device, it's all build in from the factory.

I wouldn't be surprised if they could even shut the car off remotely.
 
Don't take this the wrong way, but your haphazard terminology makes me think you don't fully understand how GPS navigation works

Best brush up on it, never hurts to learn

Satellite Navigation - GPS - How It Works | Federal Aviation Administration

Satellite Navigation - GPS - How It Works
www.faa.gov www.faa.gov

As for your day to day usability questions, most of not all factory GPS systems are completely offline (if you will), relying on locally stored map data (be it CD, Hard Drive, flash storage, etc) and the ability for it's GPS antenna to see the sky

Same goes for your (these days rather old school) suction cupped Garmin/TomTom (I don't miss those days 😒)
It's offline locally stored maps, and GPS coordinates
Maybe some saved POI data, that's usually out of date 🤨

For these two navigation solutions, no cellular service is required, as long as you're coordinates are somewhere the map covers, and your antenna can see the sky well enough to get a lock, you'll get something
God knows how useful, efficient, accurate, or up to date it'll be, but it'll be something

For the older, maybe tech illiterate, or those in rural areas who need steadfast reliability, these are the safe and easy options, but kinda limited

You mentioned OnStar Navigation, that's a different beast
For people who couldn't be bothered/figure out how to work a GPS system, OnStar offers a boomer friendly navigate me to XYZ service
You'd tell the advisor an address, or ask for a POI, they'd generate a route, then transmit it (over cellular) to your GM vehicles DIC or radio, where it would give you turn by turn instructions on screen and in spoken work
I remember my grandmother making use of it in the '04 DeVille, '08 DTS, and '12 SRX
It worked, well enough I guess 🤷‍♂️
This system is dependant on an OnStar subscription, and decent cellular coverage

Newer cars (past 5 years or so) are bringing app integrated navigation solutions on board, most popular is Apple CarPlay and Android Auto
Which is really just recasting your smartphone on the dash, in a car friendly interface
Navigation is powered by Apple or Google Maps, A few other map apps are available
These services are at their best with a cellular signal, but Google Maps let's you download offline areas so you'll have basic mapping + turn by turn, even with no coverage

They've all come a long way in the past 5 years, but you may not get 100% perfection all of the time

Now I'm a city boy, and I know my way around my locale, so a temporary loss of cell service or turn by turn hand holding isn't a big deal
But I am aware there's large swaths of inhospitable land in this country that may not be the case
 
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