Both our iAIS and WLN10 wireless NMEA devices are supplied with a small 3dB wireless antenna, which is fine on most installations. However, on larger vessels or if you have to install the device in a cupboard or behind a bulk head, it is very easy to improve the Wi-Fi range of the device by swapping the 3dB antenna for a 5dB antenna .
A 5dB antenna only costs a few pounds and is available from many online retailers. Make sure it has a SMA RP connector (this is the standard connector for small Wi-Fi Antennas) and then just unscrew the 3dB antenna and screw on the 5dB antenna (don’t over tighten). This will typically increase your range by about 30-50%.