GPS locked at a single location for the duration of my Cruise. Why?

[ximcix]

Hello guys.
I just completed my first cruise & I noticed that after about 2-3 hours from leaving Miami, my Google Maps location said I was at the Grand Bahama Shipyard in Freeport, Bahamas.
I knew that was incorrect but paid it no mind until the next day when we arrived at Nassau, Bahamas, but the GPS stated that we were at Freeport.
During this time I had my Samsung device on Airplane Mode, but WiFi, Bluetooth, Location & Sync enabled, and I was connected to the Ship's VOOM Surf & Stream data service.
The only time my location was updated was when I got off the ship in Nassau, Bahamas, and in Montego Bay Jamaica & disconnected from VOOM & far away from the ship. But as soon as I reconnected to the WiFi, my position moved back to Grand Bahama Shipyard in Freeport, Bahamas.

Might I also add that I opened the Maps app on my MacBook and it showed the same
My Cabin-mate tried the same on their iPhone and maps would not load
All devices were connected to the Ships VOOM WiFi service.

 

From my understanding, GPS doesn't really need a data service to give your location, as long as the device has an unobstructed view of 2 or more satellites. The data is used to download the map to display to the user.
I wanted to have my first cruise documented in my Maps Timeline.

Any Idea why this is so?

 

My Cruise Details:
Royal Caribbean Navigator of the Seas
Sunday March 10-15, 2019
Departed from: Port Of Miami, FL
Destinations: Nassau Bahamas > Montego Bay Jamaica, Miami Florida.

[ChickenOfTheC]

Cell phones typically use a form of GPS called Assisted GPS. That requires cell phone tower data for the your initial coarse location. There are no cell towers that accept data at sea.  You may also notice your cell phone clock will go wacky since it too gets it's time sync from cell towers. A reason why people recommend a wrist watch while cruising.

[Extra Kim]

47 minutes ago, ChickenOfTheC said:

  You may also notice your cell phone clock will go wacky since it too gets it's time sync from cell towers. A reason why people recommend a wrist watch while cruising.

Just turn off automatic updates.

[LTCSZ]

I would avoid using a cell phone for offshore for the reasons mentioned above...I use an I-Pad with the built in GPS chip and have never had any problems, especially if you try to connect through the ship's Wi-Fi service...Horribly slow and cludgy...Still looking for as good, inexpensive GPS program to go with the I-Pad, though...Most of the commercially availble programs for the I-Pad are quite expensive...Any recommendations would be welcome!

Edited March 24, 2019 by LTCSZ
Spelling, of course

[ximcix]

6 hours ago, ChickenOfTheC said:

Cell phones typically use a form of GPS called Assisted GPS. That requires cell phone tower data for the your initial coarse location. There are no cell towers that accept data at sea.  You may also notice your cell phone clock will go wacky since it too gets it's time sync from cell towers. A reason why people recommend a wrist watch while cruising.

Thanks for the info.
My phone's time was ok, even with the DST going forward an hour during the cruise.

I'm just hung up on why that specific location (Grand Bahama Shipyard) for 4.5 days. I imagine it would have placed me at random places on the globe.
Maybe Royal Caribbean has some type of communications tower there. 🤔

[ChickenOfTheC]

Without reliable location info,  Google maps may try to get your location by your IP address which is probably  registered to the shipyard. Guessing.

[Underwatr]

11 hours ago, ChickenOfTheC said:

Without reliable location info,  Google maps may try to get your location by your IP address which is probably  registered to the shipyard. Guessing.

I think this is pretty much it.

The cloud-based geolocation database correlates cell towers and WiFi hotspots with GPS-derived locations so when your device has a poor GPS fix it tries to look up locations of hotspots and cell towers it can see. This method sort of falls down when the hotspots and towers move around the earth. In the Caribbean my phone occasionally would think I was still tied up at the pier in New York.

If you begin seeing obviously erroneous position data the fix for this is to change how your device obtains its location. On my Android phone it's in Settings / Google / Location / Google Location Accuracy :

 

 

Turning this option off causes the phone to use only the GPS and not the locations of cell towers and hotspots to determine its location. 

[FionaMG]

Mine told me I was in Halifax Nova Scotia when, in fact, I was in the Southern Caribbean! I thought it might be something to do with the fact that that is where the ship had been before my cruise. 

[ximcix]

I get it.

Why this baffled me is because I can accurately track my location on flights at 10,000+ feet with no data.
From time to time I would compare my location on Google Maps with my location on the plane's InFlight Tracker.

[Heidi13]

If your device is a true GPS receiver it requires a minimum of 3 satellites, preferably 4. No idea how the cell tower positioning works,

 

To enhance the position quality, by seeing the max number of satellites, the ship's GPS aerials are at the highest points. So if using consumer GPS devices you need a good view of the sky.

[Hlitner]

I think there is some confusion by folks who think of their Smartphone as a true GPS device.  It is not!  There is no GPS antenna or GPS reception on normal Smartphones.  The so-called GPS function you get from a phone comes from the phones interaction with cell towers and/or WiFi.  But the only cell tower on a cruise ship is simply a conduit from a single satellite signal.  

 

Real GPS devices work fine on cruise ships.  We sometimes take our Garmin Nuvi (which is loaded with maps or both North America and Europe) on cruises and it works quite fine.  Like any true GPS device it will give us the ship's location within a few yards.  But this is not going to happen with your cell phone until you are within range of shore-based cells...and have a phone that is capable of locking onto those cells.

 

Hank

[Donray]

Hlitner you are incorrect.  Most smartphones have a true GPS receiver.  How do you think Goggle map has one down to within a few feet? 

 

The problem is with goggle map that does require one to receive data and not be in airplane mode. 

 

 

[Underwatr]

Hlitner, please go back and read my Post #7, with the settings available on my phone.

[Underwatr]

7 hours ago, Donray said:

The problem is with goggle map that does require one to receive data and not be in airplane mode. 

Google Maps has the option to download maps of a region so you can view maps and do basic navigation without a data connection. But the continent-level maps are built-in. I get fixes at will sitting in my cabin with the phone in airplane mode.

 

In 2012-13 I had a smartphone that couldn't get a nav fix without downloading satellite ephemeris data (which was an issue in Europe without roaming coverage) but that's a different issue.

[Extra Kim]

On 3/26/2019 at 7:11 PM, Donray said:

Hlitner you are incorrect.  Most smartphones have a true GPS receiver.  How do you think Goggle map has one down to within a few feet? 

 

The problem is with goggle map that does require one to receive data and not be in airplane mode. 

 

 

If you need a data connection to use your "GPS" you don't have a true GPS. 

[SRF]

IPhone - "Your iPhone includes a GPS chip just like the one found in stand-alone GPS devices. The iPhone uses the GPS chip in conjunction with cell phone towers and Wi-Fi networks—in a process termed "assisted GPS"—to quickly calculate the phone's position. You don't need to set up the GPS chip, but you can turn it off or enable it's functions on the iPhone."

 

 

"All models of iPhone since the 3G, as well as the iPad 3G and iPad 2 3G, include Assisted GPS (AGPS).

I’ve heard that this isn’t real GPS or that it’s somehow inferior to real GPS. AGPS is actually superior to “real” GPS. However, there are ways the iPhone is also inferior to a standalone navigational GPS like a Garmin or Tom Tom. I’m going to explain the differences between them.

 

Positioning

The iPhone includes a regular GPS receiver, just like your standalone GPS. The “assisted” part means the iPhone is able to get a quick lock based on other data sources, such as nearby cell phone towers or WiFi networks."

 

 

An incomplete list of phones with GPS - https://en.wikipedia.org/wiki/List_of_devices_with_assisted_GPS

[donaldsc]

On 3/26/2019 at 10:50 AM, Hlitner said:

I think there is some confusion by folks who think of their Smartphone as a true GPS device.  It is not!  There is no GPS antenna or GPS reception on normal Smartphones.  The so-called GPS function you get from a phone comes from the phones interaction with cell towers and/or WiFi.  But the only cell tower on a cruise ship is simply a conduit from a single satellite signal.  

 

Real GPS devices work fine on cruise ships.  We sometimes take our Garmin Nuvi (which is loaded with maps or both North America and Europe) on cruises and it works quite fine.  Like any true GPS device it will give us the ship's location within a few yards.  But this is not going to happen with your cell phone until you are within range of shore-based cells...and have a phone that is capable of locking onto those cells.

 

Hank

 

Is is not true.  All phones have true GPS devices that accurately locate your position and are capable of giving you a lat-long position without a connection to the internet as long as they can see the GPS satellites.  The problem is that you are confusing GPS location with a map location.  Unless you have one of the many excellent off-grid mapping programs, the phone will not be able to convert the lat-long location to a map location.

 

I have just put my phone in airplane mode and used my off-grid Sygic mapping program to find my current location.  I have also used another program that gives me my lat-long location even though I am in airplane mode.

 

DON

[Glaciers]

Try Maps.me