Personal Wi-Fi

[mub]

I saw a chap flying a kite from his mored boat a while back.
He had an +18dBi omni on a wifi repeater with battery pack hoisted may be 150ft in the air. Claims he got really good signal.

-- Personally at the doc I have a DSL modem on a land phone line and WAP. My marina cable internet is very poor.

Of course I have no boat in there at the moment so i have opened it for all to use.

Mub

[Son of a Sailor]

thanks for all the recommendations guys. i do appreciate it!

[D&D]

Originally Posted by hellosailor

I'd also vote for the MiFi type solution. It is a WiFi router that connects up to the cellular system, usually at a competitive rate. Anything else is probably going to get too complicated, unless you already have a cell phone with the option to be used as a "hot spot" with WiFi sharing enabled. And of course, that ties up your cell phone, making an inexpensive MiFi device a better way to go for more than occassional use.

We agree with hellosailor.

We use a 'mifi' here and it works a treat...up to 5 computers can access the net and it works wherever there's a mobile/cell phone signal which is pretty much anywhere along the OZ coast. Our little unit is battery powered, but the battery life isn't brilliant so we tend to have it plugged into AC (through an inverter and powered by SunPower solar panels) so the battery life becomes irrelevant.

Stepping away from the coast we rely upon Fleet Broadband and Inmarsat, but that's very expensive so it's used only for weather and emails.

[Jimbo485]

Onboard we set up our own wifi network with a router. To connect that to the outside world, we use a bullet antenna up the mast to grab a signal from somewhere - sometimes paid but usually free. There seem to be many dirt dwellers who simply set up their own wifi network without a password and after a while you recognise the unprotected network names on the station list (Netgear, D-Link etc). The ICW was particularly great for this.

The bullet can sometimes reach up to a couple of miles but can be relied on for no more than about 800 m. Recently we picked up the wifi signal from Tangalooma while we were coming in the channel at Caloundra, which is probably about 10 miles, but that was unusual. If there are no unprotected wifi networks around, sometimes we go to a selected bar, buy a drink, pull out the iPAD, get the password from the staff and then connect with the bullet when back on the boat.

In some countries they are more careful about passwords, so we suck it up and pay for the wifi connection through the bullet or buy a dongle and use the mobile phone network. In Australia, they often provide free wifi in the public parks, so you can anchor nearby and the bullet picks up the signal.

Onboard there is the boat's fixed PC that controls everything plus a laptop and an iPAD connected through the boat's wifi network. Sometimes we will give out our password to our nautical neighbours so that they can get connected as well. When there are 2 or 3 boats connected through our system, 2 or 3 of us on our boat using the various devices and we are piggy backing off some house, I wonder if the dirt dwellers wonder why their download speed drops so much.

[noelex 77]

Originally Posted by D&D

Our little unit is battery powered, but the battery life isn't brilliant so we tend to have it plugged into AC (through an inverter and powered by SunPower solar panels) so the battery life becomes irrelevant.
.

Typical battery life is about 6hrs.
They can be powered from 12v, with a 12v to USB (5v) adaptor. Usually one of the smaller units (1w) is fine. This will be much more efficient than using an inverter for these small demands

[SailingChance]

What have people found to be the most successful while sailing around different islands in the Caribbean?

Kelley

[Jimbo485]

Originally Posted by SailingChance

What have people found to be the most successful while sailing around different islands in the Caribbean?

Kelley

With the exception of the French islands, a bullet was the best.

Check out Bob at Island Time for the details.

[Hud3]

If you're in the U.S., there's an app called FoxFi that I use on my Droid 4G LTE to create a WiFi hotspot. It connects to the Internet through my Verizon Wireless account. I connect to it with my laptop just like I would with any WiFi network. Others nearby can see it with their WiFi network adapters, but can't use it without the password. No USB dongle needed.

[knottygurl]

Samsung galaxy phone has a hotspot built in for web access, turn it onn and connect with laptop or tablet, password protection your only limited by your data package.

[Auspicious]

Originally Posted by Jimbo485

There seem to be many dirt dwellers who simply set up their own wifi network without a password and after a while you recognise the unprotected network names on the station list (Netgear, D-Link etc).

Too bad that is illegal in most countries. It's just plain rude everywhere.

[Point08]

For once...a topic I can respond to with some useful input! I work with wireless point to point devices on an almost daily bases for security cameras and network access to remote locations on the college campus I work at. It's one of the reasons I haven't yet been able to do my live-aboard dream....my main marketable skill just isn't in demand/I wouldn't be able to get a work permit.

Depending on exactly what you're looking for, solutions for a WiFi setup are situational. One thing to remember is that you can only control your end of the transmission. This means that just because you can see an AP, that doesn't mean you can connect to it. Seeing a periodic beacon and being able to receive a critical mass of the packets sent are two drastically different things.

That being said, without getting to the definitions and complex math, the higher the dBi of an antenna, the more it can "see". It may be an oversimplification of how it works, but in general it's true. An antenna will have a radiation pattern, meaning the angle and direction that the signal that the antenna sends is the strongest when viewed at the receiver. I was going to attach graphs of radiation patterns, but they can be tough to read. Basicly, you have two main types of antennas. Omnidirectional, and directional (or Unidirectional if you prefer, although they're not truly unidirectional).

Omnidirectional is generally thought of as a single line, straight up and down type of antenna. These are frequently called "rubber duck" antennas. For your purpose of connecting to the shore, these antennas aren't as useful. This is because they put out a 360 degree circle of coverage around you. Think of their pattern like a doughnut, with the antenna in the hole in the middle. Most access points in people's homes and businesses will be using this kind of antenna. A typical gain for this type of antenna is around 8 to 12 dBi.

Directional antennas can come in several flavors. The two main ones I use are flat panel antennas and parabolic "dish" antennas. These antennas are typically much higher gain, as they focus a large area onto a smaller point, thus scooping up much more signal from a single direction. As opposed to the "doughnut" from above, think of these more like a laser beam shape...although that is overstating the tightness of their pattern. The down side to this type of antenna is that due to how tight the "beam" from this antenna is...as your boat rocks, they could point at their intended target, and then away. This is especially true if you mount them higher up on the mast. You can find dish antennas with a 24 dBi gain for less then $100, and flat panel antennas with maybe an 18 dBi gain for the same price.

I guess the best way to describe the antenna reception is that the higher the gain, the farther away it can "scoop" signals from. The issue you will run into though, is that you will also "scoop" more noise if you're trying to receive a signal from a transmitter that isn't pushing out enough power, as is frequently the case with a home wireless access point. "Noise" is the crap signal that shares the same or a similar frequency to what you're trying to receive. Basically it's anything that isn't what you want to receive, meaning it could be another access point you aren't trying to connect to. If your signal to noise ratio is too far out of wack, you won't be able to talk to the access point as you won't be able to effectively separate the "good signal" you want from the "background" noise on a consistent basis.

So, for transmission. The main thing I can tell you is to put your transmitting device as close to your antenna as possible. Coaxil cable is one of the biggest signal eating components in a system, both transmit and receive. The next thing I can tell you, is power. More is better. But there are hugely diminishing returns. Every 3 dBi of signal is a doubling of the power. So, a 1 mW transmitter is putting out 0 dBi, 2 mW is putting out 3 dBi, 4 mW putting out 6 dBi, etc....up to the FCC legal maximum of 1 Watt which is 30 dBi, I know there are many geographical areas not covered by the FCC, but mine is. There are rules about antenna gain/power combinations as well...

So....I don't know if that helped answer any WiFi questions you have, or just created more. Typically, I will use the following:

Ubiquiti Bullet M2HP (or M5HP depending on frequencies desired)
Any 24 dBi parabolic grid type antenna, they can be found on amazon and due to the grid design have minimal wind resistance.

Or, if I'm looking for an all in one package for a shorter haul, I use a Ubiquiti Nano Station M. They have a lower gain and lower transmission power, but they're compact and cheap.

[Lake-Effect]

Originally Posted by Auspicious

Too bad that [wifi stealing] is illegal in most countries. It's just plain rude everywhere.

Well.... technically, yes it is. So are littering, speeding, bumper-tailing, parking in a no-stopping zone, using a cell-phone in a hospital...

I confess that I've briefly jumped onto unlocked wifi to get mail or to look something up. Such use is usually undetectable, and is not going to exceed someone's bandwidth quota. That's my excuse...

The good news is that more and more places, including marinas, are making free or cheap wifi available, and cellphone data plans are becoming more reasonable.

[noelex 77]

Originally Posted by Point08

Ubiquiti Bullet M2HP (or M5HP depending on frequencies desired)
Any 24 dBi parabolic grid type antenna, they can be found on amazon and due to the grid design have minimal wind resistance.
.

Welcome to the forum Point08 and thanks for such a helpful first post.

Boats at anchor or on a moring swing about considerably. What sort of variation could you expect to remain connected a parabolic antenna ?. It would be nice to have an option for those situations when the omnidirectional will just not quite connect.

[D&D]

Originally Posted by Lake-Effect

The good news is that more and more places, including marinas, are making free or cheap wifi available, and cellphone data plans are becoming more reasonable.

Hear! Hear!

...and we echo noelex 77's greetings and thanks to Point08!

[Point08]

Originally Posted by noelex 77

Welcome to the forum Point08 and thanks for such a helpful first post.

Boats at anchor or on a moring swing about considerably. What sort of variation could you expect to remain connected a parabolic antenna ?. It would be nice to have an option for those situations when the omnidirectional will just not quite connect.

Unfortunately those are the situations that an omni is your best bet, but depending on how much motion you're talking about, a sector antenna could fill your need.

They typically have an azimuth of 90 to 120 degrees, although they still have a tight vertical profile. Think of their pattern like a UFO. Wide at the middle like a disc (90 to 120 degrees), thin at the edges and a little bit fatter in the middle, So if you kept it near the deck to minimize the rocking, it could cover a wider swath of the horizon. You can probably get away with a 10 degree elevation change with that type of antenna, where with the grid type antenna you might get a 3 to 5 degree change if you're lucky. Sector antennas are typical for cell towers.

The biggest problem is that the more area you want an antenna to cover, the lower the gain will be. Think of the end point that you're trying to transmit to as something that moves around, and if you want to be able to have a quality signal 90% of the time, you need to make sure that the antenna you use would have that point in it's radiation pattern 90% of the time. My honest opinion would be to keep a selection of a few different antennas available, and don't mount them up too high due to the amplified motion of the mast. I forget the formula, but there is an optimal mounting height for antennas base on distance and angle to target...I don't know what effect water would have on that, because it typically eats up 2.4Ghz signals, it's a bit outside of my current knowledge.

<edit> I forgot to add, thanks for the welcome. And I was glad to see that you pointed out the danger inherent in using "open" WiFi access points. It is fairly easy to set up a man in the middle attack on a network designed to lure a would-be thief, and most folks wouldn't know it was even happening.</edit>