high quality active high precision gps antenna,multi LNA GPS/GLONASS/BEIDOU/GALILEO

Top quality GNSS antennas for optimal positioning performance
An important factor in ensuring best positioning performance of your GNSS receiver is the right GNSS antenna. These antennas have been carefully selected and verified to work together with GPS receivers under challenging conditions to deliver accurate positions.

Q:Should you use GPS with GLONASS?
A:Actually only gps should do its job in case satellite reception is perfect. 
The combination with another system will improve accuracy when the signal gets weaker.
Q:Does GPS work without an antenna?
A:GPS (Global Positioning System) systems work by receiving signals from satellites. 
That isn't possible without an antenna
Q:Where to put a GPS antenna?
A:In most cases, you can mount the GPS antenna near the top of the underside of your dash (behind or above the receiver).