I have been testing one of these units for about a month. I get some GPS data fixes without any(!!) GPS antenna with the unit inside a two story house. If I put my finger over the SMA connector I loose the signal almost immediately. This is impressive performance. The unit is putting out GPS strings at all times, but the data fix is missing and unreliable under these conditions. We have to assume that any fix derived under similar conditions is a function of the overhead satellite configuration at the time. The fact that it gets a fix is amazing. The unit appears to put out about one string each second for the five or six string message types that it generates.
A normal GPS antenna is generally a patch or spiral unit of some kind. They may have some internal amplifier circuitry and use some power from the AO-26 or similar such units; just in case you were wanting to try a simple piece of wire. After all GPS is around 1.5 ghz and a 1/4 wave is only a few inches.