Life without the internet: It's almost unimaginable - even the weather forecast is impossible without it. A weekend perhaps, but not a whole holiday offline. And if you use the signs of the times to switch from the office to the boat office, you can't do without the internet. Wi-Fi is available free of charge in almost every harbour, as well as in many cafés and via hotspots, some of which are chargeable. So you'd think it would be easy to get online on holiday without putting too much strain on your mobile data volume. Unfortunately, the picture is often different on the boat: the harbour network is difficult to receive at the berth, the connection is often interrupted and it is slow. It's not just online junkies who get frustrated.
Here we show you the most common ways to improve the situation. The first thing you should realise is that, in principle, WLAN works in the same way as radiotelephony. The only difference for the user is that data rather than voice is transmitted. However, as the transmission power and the antennas are much smaller, the WLAN connection does not work over miles, but only a few hundred metres at best.
WLAN antenna and device should have line of sight
For high transmission rates, WLAN must operate at very high frequencies. 2.4 GHz or 5.8 GHz are common. The radio waves behave very similarly to light: the connection is only established if both stations can see each other clearly.
A detour for technology freaks: VHF marine radio operates at 156 MHz (that's 0.156 GHz) and still goes well through buildings and a little "round the corner". Data is also transmitted here for the DSC functions, but at the speed of an untrained person at a mechanical typewriter. This would therefore not be an alternative for the Internet.
Line of sight is the first starting point for improving Wi-Fi reception on the boat: Go upstairs with your tablet or notebook. The connection is almost always better in the cockpit than in the bunk. The aim is to be able to see the harbour's Wi-Fi base station (the so-called access point). This is either located on the harbour master's building, or there are several of them distributed on the bridges.
As with light, there are also shadows and reflections with radio (WLAN). The only difference is that it is not so easy to see where the good areas are. Changing your sitting or lying position often causes you to move your device between bright and dark areas, i.e. between good and poor reception. Simply turning round when the connection is poor can help. Or it can also go wrong so that there is no network at all, in which case you just have to go back. But it's worth a try.
Where the good spots with a good network are on board depends, as with light, on the position of the sun in relation to the ship. Here, of course, we are referring to the radio sun, i.e. the WLAN access point. The conditions therefore change from harbour to harbour, from berth to berth, sometimes even if you put your boat in the same box the other way round.
Rain can disrupt the WLAN connection
Plastic superstructures and tarpaulins are not normally a major radio obstacle - as long as they are dry. In the rain, it helps to open the side in the direction of the access point, if this is practicable with the wind direction.
Larger harbours have more than one access point: You can see this by the fact that the harbour network appears several times in the Wi-Fi list on your mobile phone. Which of these provides the best reception can vary greatly depending on where you are. Whether switching between the different access points of the same provider works automatically depends on many settings, both in your device and in the harbour network, and is rather unlikely. So if you log into the WLAN at the harbour master's office immediately after logging in, you will probably no longer have a good network back on your boat. Don't get annoyed, but first check whether you can find another access point with good signal strength.
Up to this point, the reception improvements did not require any investment or hardware modifications, but this has now been exhausted. And they were all unusable with a permanently installed computer or plotter with WLAN. The next optimisation step is an external antenna for the wireless network.
Antenna with or without your own WLAN stick?
There are basically two different types: There are pure antennas that are connected to the computer via a high-frequency cable and otherwise use the computer's WLAN hardware. And there are devices that look almost identical and contain their own WLAN stick in addition to the antenna. These are connected to the computer via a data cable and the latter does not need to have WLAN functionality itself. It is therefore important to read the description carefully when choosing the right variant.
The prerequisite for using the pure antenna is that your device has a WLAN antenna socket. This is almost always the case with permanently installed on-board computers, rarely with plotters and almost never with notebooks. You don't even need to look for it on mobile phones or tablets.
The outdoor versions for remote houses are quite inexpensive. They have a rainproof housing, achieve good results thanks to their directional effect and are available from around 25 euros. On a boat, however, they are at best suitable for optimising reception at a fixed mooring, as their mounts are not designed for constant repositioning, and a flying installation is not practical due to the directional effect and bulky cables.
Omnidirectional antennas do not need to be aligned
WLAN antennas for marine use generally have equally good reception all round, so there is no need for alignment. The technical term for this is "omnidirectional antenna". They are also waterproof from all directions and optimised for mounting on the boat. Prices start at around 90 euros. The term "gain" is always used in connection with antennas, expressed in the unit "dbi". The higher this value, the better the connection, but the larger the size and the higher the price.
The biggest problem with pure antennas is the cable to the WLAN hardware in the computer. This is because the high frequency results in large losses. To ensure that the improvement from the external antenna is not eaten up by just three metres of connecting cable, high-quality versions with professionally processed plugs are required. The technology used in marine radio is unsuitable for WLAN. For the shortest connection cable alone, you would have to reckon with an additional 50 euros, with ten metres the 100 euros are quickly reached. Even longer cables make no sense because of the losses.
A pure antenna is practically only an option if you only need to use a short cable to get out of an area with poor reception, such as the steel hull. And only for a single computer that already has WLAN hardware with an antenna socket.
WLAN stick with antenna for occasional use
To improve the network connection for a notebook from time to time or to try out the potential of larger solutions, you can purchase a USB WLAN stick with an external antenna. You will need to invest from around 30 euros for this, but sometimes the antenna supplied is sufficient for adequate reception. Of course, this is not waterproof or even suitable for outdoor installation. And with frequent assembly and disassembly, the filigree antenna cable does not have a very long life expectancy either. However, it is a good starting point and a good basis if you want to realise WLAN antenna construction ideas from the Internet.
The high-frequency cable problem of the pure antenna can be elegantly avoided technically if a WLAN stick or network router is integrated directly into the antenna base. This is also sometimes marketed as a WLAN antenna, so please take another look: High-frequency plugs are round, data plugs tend to be rectangular (see picture gallery above).
Antennas with a modem are available with a USB or Ethernet connection from around 180 euros. The former is easy to connect and, above all, you don't need to worry about a power supply. If you work with iOS or Linux as your operating system, you need to make sure that the appropriate drivers are available. However, USB has another cable problem: from five metres upwards, you need special active extensions, more than 30 metres are only possible with very expensive adapters.
With the Ethernet connection, the cable length only becomes a problem on cruise ships. More effort is now required for the power supply. Either a separate cable to the antenna, or a switch that feeds power into the network cable. The advantage of the Ethernet version is that it directly supplies a network to which any computer can be connected regardless of the operating system, without any driver installation. An example of such a WLAN modem with an Ethernet connection is the Scout Rocket shown in the picture gallery above. It mechanically represents the base under the WLAN antenna, so to speak.
A router is required for multiple devices
All of the solutions described so far allow exactly one computer to access the harbour Wi-Fi. However, the aim is to improve the connection for all devices on board, and there's not much left to do: the Wi-Fi modem from the last variant is not plugged directly into the computer, but instead feeds a Wi-Fi router below deck. This creates an on-board wireless network, so to speak, which all your smartphones, tablets, e-book readers, computers and plotters can log into.
Publicly accessible wireless networks usually require you to log in before you can surf. Cleverly configure your router-modem combination so that the WLAN modem connects to the harbour network as a client. Everything on board will then look like the same device to the harbour, i.e. you only have to register your ship once in the shore WLAN and not every single device on board. Whoever wants to access the Internet first in the harbour will automatically be shown the login page. Once this has been confirmed, all further accesses from your on-board network will lead directly to the network.
The WLAN antenna with modem and the router required on board will cost you around 300 euros. As the configuration of the two components is not easy, it is advisable to buy the whole thing as a package from a dealer who you can contact directly if you have any problems. If you use chargeable hotspots with this system, remember to secure access to your on-board WLAN. Otherwise a few unwanted fellow surfers can easily find their way in.
Mobile router requires a SIM card
Depending on the season and the harbour facilities, the Internet may be slow despite perfect radio contact. This is usually because the harbour's connection to the network is being used to capacity by numerous users. Your last chance is then to make the ship's WLAN independent of the shore WLAN. However, the days of free Internet are over: a mobile router establishes the Internet connection via the UMTS or LTE network, which of course requires a SIM card with a suitable contract.
The system with the simple router can be expanded in this way, but it becomes inconvenient as you have to configure two devices when switching between WLAN and mobile radio. It is also cheaper to purchase a complete solution such as the Webboat from Glomex or the Scout Sea-Hub plus. Both cost between approx. 550 and 600 euros, and they support automatic switching between harbour WLAN and mobile network.
This article first appeared in boote 9/2020
