In-line GPS amplifier

I was having trouble with my GPS nav system in my car loosing the sat signal during rainy,cloudy and stormy conditions. So I designed this inline GPS amp using a device from Maxim. **broken link removed**

Below is the circuit, pcb layout and network analyzer response. Works very well. The SOT caps on the input were selected to improve the noise figure of the device.

ya oughta put that in the projects section. thats a cool little circuit to be able to do wut it duz :lol:

TheOne thats a very interesting project. I am looking for a project like this for my own GPS.

I would like to know if you still have the schematics files of your desing and I want to know if you can share them with me.

I can see tha the circuit has like an array of LC filters conforming the antenna, and I wonder if it was hard to tune the antenna with the those varicaps. Wich procedure did you use to achieve this?

I suppose I will need a field meter (I really don't know if thats de correct name in english), and that it won't work at fist time without calibrating it in a lab.

Thanks
Sebastián

This circuit will be very difficult to align without a RF network analyzer (RF tracking gen and spectrum analyzer combined)

Wich software did you use to make the circuit and the PCB? can you send me those files?

On a practical level, there are self-amplifying GPS antennas. I've got one that's maybe 1.5" x1.5"x0.5", magnetic so it sticks to my car roof, and has a tough thin wire that can be slammed in the door seal indefinitely. That thing will aquire in a few seconds and only a tunnel can interfere with it.

Oznog said:

On a practical level, there are self-amplifying GPS antennas. I've got one that's maybe 1.5" x1.5"x0.5", magnetic so it sticks to my car roof, and has a tough thin wire that can be slammed in the door seal indefinitely. That thing will aquire in a few seconds and only a tunnel can interfere with it.

Click to expand...

I understand as a self amplifying antenna as an antenna module with a built in amplifier, thus it is not a pasive component. And that is what I am trying to do. I think that an amplifier is a must have in my case, ´cause what I am building is a reradiating antenna.

Of course that the practical way maybe is to go and buy one....but I don´t like the easy way 8) And here in Argentina is very expensive.

The problem is that I don´t hace experience and the knowlegde needed to build the right PCB. That´s the reason I am asking for help. Then I will need some help to tune it up.

Bye
Sebastian