Note : wifi signals are very weak and anything that can cause losses must be avoided. The lengths of USB cable or coaxial cable antennas and connections are the main sources of losses.
Types of antennas :
High performance – Bullet family The best solution to avoid coaxial cable between antenna and radio is to plug directly the antenna in the radio. And to avoid USB cable the best thing is to use ethernet protocole. Ethernet cable allows transmission over lengths up to 100m without loss and also serves as power supply cable (POE, Power Over Ethernet) Badboy, TheWirie, WL510 Rogue are made up of the same components. The wifi receivers are all Bulbi from Ubiquiti, the differences are in terms of accessories, design and price. The original is the Ubiquiti Bullet M2. For the antenna, an omnidirectionnal of 8dbi seems to be the best compromise. Warning: if you choose to purchase a Bullet rather than Badboy or other, it will have to be configured. It is not very complicated but for a neophyte in computer network, we advise against it. All these solutions are of very good quality and can under certain conditions allow you to connect to a wifi hotspot up to 10 miles and more. In practice, the truly exploitable connections are up to 2.5 miles.
Update 04/2018 : Best Performance / Quality / Price: Ubiquiti now offers a bullet dual band 2.4Ghz/5Ghz Bullet Dual Band B-DB-AC . It is sold for 80€ and in stock at Eurodk. He doesn’t appear on ubiquiti’s website yet. With a small dual band antenna, it is surely a very good solution for the yachtsman.
Antenna USB – Les moins chères : Cheapest: These antennas directly connect in USB. AlfaNetwork has been producing the AWUS036 for years. At 30 € they are of excellent value for money. Inevitably it is more constraining to the length of the cable, it is not waterproof, the range will be less but it works very well. Now you have AWUS036ACH with wifi 5Ghz. With our hotspot it could be work perfectly.
Directional – Economical and very efficient solution : Ubiquiti, in addition to the famous bullet, offers radio with integrated antennas. This is the Nanostation Loco M2. For 65 € these are excellent antennas, ready to be fixed on a tube.
The Nanostation M2 120 €: Model a little more powerful in emission. Almost the same as the previous reception.
The Nanostations are directional antennas. They receive and emit 60 ° vertically and 60 ° horizontally. This goes well on an anchorage that does not swing too much.
12v power supply – All these antennas can be powered
Directly with the 12v of the boat thru the ethernet cable. It takes either a small fitting like this or stripping the network cable just connect the blue pair to the positive and the brown pair to the negative.
If you want to protect your antenna as much as possible from electrical interference, a small regulated power supply converting the 11v ~ 14v from boat into stable 24v.