In search of accurate GPS module

Hi there,
I am currently working on a project which has requirement of a accurate GPS module. I will be fine if there is error of ±2 meter (in practical life). Please recommend some GPS module. Also what is the practical error in those cheap GPS modules ?

thanks

Kaizen_Inventor:
Also what is the practical error in those cheap GPS modules ?

Depends a great deal on how good a view the GPS has of the sky and the horizon, and you did not say where this GPS will be used.

Outdoors, with a good unobstructed view of the horizon, you might sometimes get +-2m accuracy but most often its +/-5m or more. You have no real way of telling how accurate the fix actually is unless you know specifically where the GPS is located.

If you look you will find a forum specifically for GPS;

Networking, Protocols, and Devices - I2C, SPI, XBee, GPS, etc.

thanks for quick reply

I am actually going to put the GPS module inside my vehicle for a project. Also, I need to collect data fast so hence it must also have high update rate. I did some research and found that some module have 10 hertz of update rate, What does that mean ?. Also I think it would be OK if I get accuracy between 5m.

“Hz” is another way of saying “s-1”, so 10 Hz means ten updates per second.

I am actually going to put the GPS module inside my vehicle for a project.

Depending what your unspecified vehicle is made of, that could be a problem

Well you want three things at the same time. High accuracy, speed and cheap price.

With GPS you can have very high accuracy if you have a lot of time and you know how to process the data to remove errors.

Because you are moving you will not get more accurate. That is why car build in systems use the information of the steering and the map to tell you where you are. They do not really know, but they assume you are not inside a building driving at 60mph and they know you are steering right now so, you are likely already at that next corner.

Survey GPS equipment with very high accuracy cost a lot of money and they do not move during the measurments.

The accuracy of your location is in relation to the whole planet. Do you really need that or can you compensate by using other sensors? I have not heard of somebody getting lost because GPS is not accurate enough. :slight_smile: We simply use other sensors for the rest of the way.

Kaizen_Inventor:
thanks for quick reply

, I need to collect data fast so hence it must also have high update rate.

So how are you going to filter it? GPS positions vary each reading - so while you are collecting a lot of data the position from one reading to another could be +/- 5m or so - depending on the unit and the view of the sky - so you could have some very high speeds between to successive readings while you are standing still