The distinction between "active" and "passive" antennas is rather arbitrary once you include antennas integral to the module..
All GPS modules will have some kind of low-noise amplifier (LNA) in there. When you are talking about external antennas connected by a (potentially) long piece of cable, it becomes advantageous to put an amplifier at the antenna end of that cable - to minimise the impact of losses in the cable. If you had the same amount of gain in an amplifier at the other end of the cable, it is now amplifying proportionately more noise and less of the wanted signal than if it had been placed at the other end.
When you are talking about an antenna integral to the module, the amplifier is adjacent to the antenna regardless of whether you consider it to be part of the antenna or not.
For the same antenna (size, construction), best is to have it integral to the module, almost as good is to have it as an external passive antenna (ie. LNA placed with the antenna, cable to the GPS receiver), much worse is to have the antenna external but passive (LNA separated from the antenna).
The main reason for having an external antenna is so that you can put it in a more favourable location - at least facing upwards. For some classes of product this is a big deal (if there's no convenient location on the product itself to fit the GPS module such that the antenna is guaranteed to face upwards). Dashcams in cars is one such example - there's not much choice of where to install it as the camera needs to be looking out of the windscreen, and so at best the GPS also has a view out of the windscreen covering less than half of the sky; worst case the windscreen has a metallic coating which suppresses the GPS signal. So in this case having a socket for an external antenna lets the user install one somewhere more useful.
You can also fit an external antenna if it is better (typically bigger) than the built-in one, and of course in that case you want an active one to gain the maximum benefit, but usually that means you should have bought a better one in the first place.
All GPS modules will have some kind of low-noise amplifier (LNA) in there. When you are talking about external antennas connected by a (potentially) long piece of cable, it becomes advantageous to put an amplifier at the antenna end of that cable - to minimise the impact of losses in the cable. If you had the same amount of gain in an amplifier at the other end of the cable, it is now amplifying proportionately more noise and less of the wanted signal than if it had been placed at the other end.
When you are talking about an antenna integral to the module, the amplifier is adjacent to the antenna regardless of whether you consider it to be part of the antenna or not.
For the same antenna (size, construction), best is to have it integral to the module, almost as good is to have it as an external passive antenna (ie. LNA placed with the antenna, cable to the GPS receiver), much worse is to have the antenna external but passive (LNA separated from the antenna).
The main reason for having an external antenna is so that you can put it in a more favourable location - at least facing upwards. For some classes of product this is a big deal (if there's no convenient location on the product itself to fit the GPS module such that the antenna is guaranteed to face upwards). Dashcams in cars is one such example - there's not much choice of where to install it as the camera needs to be looking out of the windscreen, and so at best the GPS also has a view out of the windscreen covering less than half of the sky; worst case the windscreen has a metallic coating which suppresses the GPS signal. So in this case having a socket for an external antenna lets the user install one somewhere more useful.
You can also fit an external antenna if it is better (typically bigger) than the built-in one, and of course in that case you want an active one to gain the maximum benefit, but usually that means you should have bought a better one in the first place.
Statistics: Posted by arg001 — Thu Jan 16, 2025 10:13 pm