How does GPS work if no satellites?

Quote from: jroa on February 16, 2014, 12:18:44 PM

I do have a dedicated GPS unit.  However, I use my phone most of the time for convenience; especially because it allows me to easily download Geochache information, where as my dedicated GPS does not. 

One of these days, I will need to do a side by side comparison between the dedicated unit and my phone.

I've done a bit of that hiking in places like Scotland - the iPhone is pretty good - bang on most of the time in terms of longitude and latitude, but sometimes seems confused over altitude (which is much less important when walking).

Off topic.. the iPhone is an amazing bit of kit.... accelerometers, compass, gps, gyro's.. i find it amazing... all the processing power, the apps.. the list goes on..

Sooo...is anyone going to tell me how GPS calculates altitude without using satellites?

Sooo...is anyone going to tell me how GPS calculates altitude without using satellites?

Well jroa seems to be the authority on that question but he seems to be busy playing the number game. It seems the flat earth forums most popular thread is one where you can display your ability to +1 to a number...if only they put the same effort into their theories 

You would be surprised about how many people screw that up. 

You would be surprised about how many people screw that up.

I'd be much more surprised if you told me how the GPS system provides altitude without the use of orbiting satellites.

How did Loran work with no satellites?

Pseudollites are stationed around the disk, and your position is triangulated from these beacons.

I picked satellites. Please do not expect answers to multiple questions in a thread. It makes them jump all over the place as people answer different parts..

Where are the pseudoliti stations in Balkans?

How did Loran work with no satellites?

Pseudollites are stationed around the disk, and your position is triangulated from these beacons.

I picked satellites. Please do not expect answers to multiple questions in a thread. It makes them jump all over the place as people answer different parts..

GPS does not use technology LORAN

GPS VERSUS LORAN-C FOR
VEHICULAR NAVIGATION IN URBAN
AND MOUNTAINOUS AREAS

From the limited test results presented here, it appears that GPS is now better than Loran-C in term of signal availability in a urban area The use of fast t-e-acquisition receiver technology is a significant factor, especially in areas of high buildings and forestry canopy. The use of an integrated GPS/Loran-C results only in an availability increase of a few percent. A more extensive study is however required to confirm these findings and ascertain the availability percentages presented herein

http://www.novatel.com/assets/Documents/Papers/File10.pdf

Please don't necro 5 year old threads. 

Please don't necro 5 year old threads.

please answer. I just look for answers

Why don't you ask Thork?  Oh, wait, he hasn't been here in 3 years. 

Why don't you ask Thork?  Oh, wait, he hasn't been here in 3 years. 

I ask you.

It says here that GPS not use technology LORAN

http://www.novatel.com/assets/Documents/Papers/File10.pdf


 satellites exist? GPS? explain this

Quote from: jroa on February 08, 2016, 02:06:29 AM

Why don't you ask Thork?  Oh, wait, he hasn't been here in 3 years. 

I ask you.

It says here that GPS not use technology LORAN

http://www.novatel.com/assets/Documents/Papers/File10.pdf


 satellites exist? GPS? explain this

There are more pseudolites mounted on cell phone towers now.

Quote from: Firmament on February 08, 2016, 02:11:38 AM

Quote from: jroa on February 08, 2016, 02:06:29 AM

Why don't you ask Thork?  Oh, wait, he hasn't been here in 3 years. 

I ask you.

It says here that GPS not use technology LORAN

http://www.novatel.com/assets/Documents/Papers/File10.pdf


 satellites exist? GPS? explain this

There are more pseudolites mounted on cell phone towers now.

Proof please.

Has anybody thought about figuring out what satellite dishes are pointed?

They are directional.

They need to be set up with a certain azimuth and elevation.

Wouldn't just using triangulation using different locations at the very least give an idea of the altitude and location of the signal source?

This site gives you the information you need to set up a sat dish.  I think it is safe to assume the information provided is accurate.  If it was not people could just set up the dish and not worry about LOS and just set up the antenna.

http://www.sadoun.com/Sat/Installation/Satellite-Heading-Calculator.htm

You can find other sources if you wish or find friends and family using a satellite service and ask them where their dish is pointed. You could also ask them what happens when they start moving the dish around to prove it is not an omnidirectional antenna.

Wow.  I did not realized the GPS uses satellite dishes.  Please tell us more of this fictional land that you made up. 

Wow.  I did not realized the GPS uses satellite dishes.  Please tell us more of this fictional land that you made up.

They do not which I assume you already suspect I know that. Satellite TV services claim they are sending you a signal from space.  If you can triangulate where the signal is coming from then a conclusion can be made that satellites exist.  If satellites exist then why would they feel the need to lie how GPS works?

I assumed you and others have the capability to infer what evidence this would give to the argument that GPS uses satellites. Am I wrong and you were unable to make the connection?

So, your whole spiel about satellite signals needing precisely aimed dish receivers was just BS? 

So, your whole spiel about satellite signals needing precisely aimed dish receivers was just BS? 

I have used Dish network when not living on a boat.  If I did not have the dish set up correctly I did not receive a signal.  Which means it was a directional antenna.

I have used satellite comms in the military and the same applied.  I had different azimuths and angles I needed to set the dish at.  I could not just set up the antenna any way I wanted.  The closer I set it to the correct azimuth and elevation the stronger the signal I got.

The difference between GPS and sat TV is the bandwidth used. 

The amount of data needed to be sent is different.

GPS satellites are not in geostaionary orbits.

For GPS to work it can not use a directional antenna since the signal needs to be received from other satellites and the satellites need to send signals to each other.

Basically the receiver does not need to be directional for PS to work.

Triangulating the position of a GPS sat would be relatively more difficult considering the equipment most people have access to.  Triangulating where a TV sat in geostationary orbit is poses less problems.  Since it remains in the same position over the Earth and just a matter of  figuring out where the antennas need to be pointed at different locations.  Draw lines from those antenna and see where they intersect.

So, your whole spiel about satellite signals needing precisely aimed dish receivers was just BS? 

Satellite tv proves satellites exists.  Hence satellites can be and are used for GPS (the specific GPS service we use today).

So if your GPS position is based off of pseudoliti or what ever you call them. Would there not have to be a station mounted on every ridge to give an accurate location. The GPS frequency is very weak and will not transmit through anything that you cannot see through. As well the elevation irregularities on you phone has to do with the fact that the gps signals that it is receiving are only the L1 frequency. While only the L1 frequency can give a good a altitude location it does have to log the data from the satellites for a considerable amount of time as well as be post processed by the data provided from the NGS CORS sites. Now to the comments about good gps handhelds, it really has more to do with software that is interpreting the data than actually with the hardware in the units. All of your standard handhelds, including your phone only operate on the L1 signal, and in all reality are the same. A major difference in performance does occur when you add the L2 Frequency and the soon coming L5 Frequency, but those two are only found on Survey Grade Gps Units.

Is there a cell phone tower on every ridge?  My cell phone can tell me exactly where I am, even with the GPS turned off. 

Is there a cell phone tower on every ridge?  My cell phone can tell me exactly where I am, even with the GPS turned off.

Try it out at sea.

Quote from: jroa on February 17, 2016, 02:20:49 PM

Is there a cell phone tower on every ridge?  My cell phone can tell me exactly where I am, even with the GPS turned off.

Try it out at sea.

You think I have never been to sea? 

Quote from: LuggerSailor on February 17, 2016, 02:57:55 PM

Quote from: jroa on February 17, 2016, 02:20:49 PM

Is there a cell phone tower on every ridge?  My cell phone can tell me exactly where I am, even with the GPS turned off.

Try it out at sea.

You think I have never been to sea?

No, I'm just saying that location services on your phone (when it's GPS is switched off) don't work when out of sight of the land-based cell phone masts.

The point I was making is that the gps signals are very weak and can't transmit through mountains. An anology that is used is that the strength of the gps frequency is as bright as a 60 watt light bulb in New York and seen in LA.

The point I was making is that the gps signals are very weak and can't transmit through mountains. An anology that is used is that the strength of the gps frequency is as bright as a 60 watt light bulb in New York and seen in LA.

In order for that 60 watt bulb to be detected in LA, the world would have to be pretty flat, wouldn't you say? 

Analogies not your strong suit I see. After reading  10 pages of thoughts on how GPS works. I was just trying to explain how it actually works and why a land based system would not at this time. Don't get me wrong I would love to see a enertial positioning system like you think GPS is we just are not there yet.

Analogies not your strong suit I see. After reading  10 pages of thoughts on how GPS works. I was just trying to explain how it actually works and why a land based system would not at this time. Don't get me wrong I would love to see a enertial positioning system like you think GPS is we just are not there yet.

It's an analogy if you say something that contradicts your own view of the shape of the Earth? 

I don't really understand your way of thinking, and I can see you don't actually want to have an intelligent conversation. But I have to ask this, in your world is a mile not 5280 feet? I know the distance from NY to LA would be slightly different on a flat earth as opposed to the real one we live, but not that significant of a difference to effect my anology.

I don't really understand

We know...