15km High Speed Wifi Link to a stationary boat. ADVICE!

[Adamu]

Hi All,

I have a client who requires a 25mb/s wireless ethernet data link (point to point) between two points.

DETAILS:
Base station: Elevation of 35m, fixed to ground.
Boat: Elevation of 5m, Constant rotation of 90deg, Constant List of 10deg. (2 point mooring in sheltered waters, boat length 4m) FIXED LOCATION.
Distance: 15km

The main data throughput is from the boat to the base station feeding two live HD video streams to the internet. (20 mb/s total)
Data transfer from Base station to boat is minimal. (1mb/s) (Command and Control)

There is a clear line of sight between both points but entire distance is over ocean with wave conditions averaging 1m wave height with a maximum of 2m.
Average wind speeds of 20 knots, maximum 50 knots. Salt water environment.

Location is Australia. I am happy to use (semi legal) 'boosters' to increase output, as this practice is common and the area has minimal population.
I expect some interference in the 2.4ghz range and possible marine radar interference but I think 5ghz range will be relatively clear.


I have spent some time investigating options and I have come up with two main ones that I hope may be viable:

OPTION A:
Boat Antenna: 15dBi Omnidirectional
Base Station Antenna: 36" Dish Antenna (31 dBi)
Link: TrangoLINK-45 or similar


OPTION B:
Boat Antenna: 36" Dish Antenna (31 dBi) on a track-it-tv.com tracking mounting
Base Station Antenna: 36" Dish Antenna (31 dBi)
Link: TrangoLINK-45 or similar


I am looking for advice and/or sales pitches for equipment that will be capable of this link.
Any advice would be greatly appreciated as I realize this is pushing the limits of this technology.
I suppose the next question is also how far can you send 20mb/s to a swinging/rolling vessel from a ground station?


Many Thanks,

Adamu

[jeremiason]

I have been using Radio Labs Marine Wifi 8db gain Antenna for about 6 years... They recently developed a large 12 db gain omni directional antenna that may fit your needs...

Marine Wifi Antenna || Long Range - RadioLabs

[evm1024]

I've got a few Antenna on headlands and can get out 42 nm to ships. Ship antenna height is 60', headlands are 230'. I use an antenna/ biamp combination to give an ERP of 4 watts which is legal where I am.

I use the biamps for the receive gain rather than the transmit power. Typically I use 15 dB omni for the ships and 15 dB (or more) sector antenna for the shore side. I want the power going offshore. And the shore station not hearing the transmitters landward.

I use lmr-600 or lmr-900.

Some thoughts:

Don't use a parabola unless you have a spectrum analyzer or other tool to help aim it. My experience is that dishes are very hard to aim and that the beam center is not at the visual center.

Power is not a prescription for distance (unless we are talking antenna height and 100s of watts). Go for the best S/N ratio you can get. THis is why I use sector antennas for area coverage and yagi for fixed hops on the backbone.

Be aware that birds will sit, **** and nest on horizontal antenna sections. Then the antenna will rotate.

Build it so that it is east to maintain. Salt, rain and other weather will work against you.

Lastly, getting bandwidth is difficult. as the S/N ratio goes down the radios I use will drop the bandwidth to compensate.

THe best distance I've ever gotten is 105 nm. I had 2 headlands associate once. The 2 radios has each others mac addresses so I presume that they were at least for a short while exchange tcp/ip packets for routing. Gotta love UFH ducting.

Good luck

Regards

[JesperWe]

When using highly directional antennas on the land side, make sure that they have SOLID mounts. A directional antenna doing even very small swings in the wind will have adverse affects on bandwidths, since the radio DSP will need to rebuild its channel model very often.

Obviously a highly directional antenna is not a good idea on the boat side of things.

[Lake-Effect]

Option C:
first hop - boat to nearest shore - a tall building, or small tower or pole, with clear RF path to base station. Assuming boat to shore point is under a km, you have many reliable options for boat to shore
second hop - shore point to base station. Directional antennae and appropriate radios for 15 km

Yes there's cost and hassle for the added midpoint, but maybe that cost could be defrayed by reselling internet access to others at the remote location?

[Adamu]

Thanks Guys for your input here, this problem just has way to many options and not enough tested solutions!

I can rule out jeremiason omni antenna because it is USB and not a point to point system so I have serious doubts as to it been able to sustain 20m/bits data rate.

Lake Effects hopping idea also is not an option due to geography, 15km is the closest point to land.

evm1024, seems to have the right idea and is talking more like i am thinking and where my research has lead me.

I have decided to not go the tracking option for this first install because I want this design to be very simple and very reliable with minimal maintenance. 15km links shouldn't require tracking.

So lets talk antennas!
Which would be the best omni antenna and booster combo to have on the boat? (5ghz)
What would be the best sector antenna for the land side? Or should I just stick to the one already supplied in the TrangoLink setup (Panel, 24dBI, 9deg beam width)??

Should I have boosters on both ends? Or just the boat side? Remember the data is going from boat to shore.

I would love to hear more about your setups evm, and whats speeds you can get over these distances? Just remember my boat antenna can't be any higher then about 8m.

Thanks for your helps folks, I feel I am finally narrowing the options.

Adamu

[hellosailor]

"Remember the data is going from boat to shore."
Nope. Even if you're just streaming one way, the system is sending both ways, to acknowledge packets, or have them resent, etc. You want a system that runs with the same power/sensitivity both ways.

[F51]

HS: you are correct, it is bi-directional, but the acks and re-transmit requests are much smaller packets than the streaming video. These types of links can work very well highly asymmetrical.

[SunDevil]

Antenna, Wireless Accessories, Wireless Antennas

Industrial Wireless Network Soutions - B&B Electronics

Not associated with this company either, and I'm sure there are others out there.

I'm not an expert by any means. I do get TV from 50km away using an antenna. And I have done some wifi stuff. My first ISP had a big antenna on the mountain and gave people square shaped antennas to receive data from 20km. So, it is possible.

The tips I can give you is to have as short of runs of the antenna cable as possible before converting it back into ethernet, and have powerful antennas on both ends. It does very little if you only put a huge antenna on one side. I would try the omni-directional one first, but be sure they have a return policy. It would be nice if the omni one works, since it has fewer things that can go wrong. Also look into lightning protection, and factor in the loss of signal amplification.

You will have to contact these companies or the antenna manufacturers to tell you what would work the best in your situation. Make sure it is over engineered by 25% to account for rain or interference.

[hellosailor]

F51-
Asymmetrical has nothing to do with it. If the stream from the land to the boat is not powerful enough, those ack/naks etc. will not be received and the datastream will remain corrupted. And, if they are not received on the boat, the land tower is going to drop more packets and slow down the bandwidth even further as it tries again and again to send those packets.
So the question is whether the land tower is sending a powerful enough signal to be received on the boat, as well as whether it is sensitive enough to receive the signal coming into it. Generally speaking, any radio transmission pair will be limited by the weaker side of the pair. If one site is weaker, slower, less sensitive, it is going to impact both directions.
How much power and sensitivity either side needs is a whole other question, but it should be "How much is needed for this path?" not just for one end or the other.
Can you get away with less for the tower, and simply eat the overhead caused by the boat not receiving half or three quarters of those signals from the tower? Possibly. I'd have to expect this is like any other ethernet/IP connection, where the user may never notice a lot of noise and failures until somebody tweaks it--and then they notice how much faster it gets.

[SoonerSailor]

On the land side, go with the highest gain antenna you can reasonably install. This probably means a good size parabolic dish. Since antenna gain works both ways, transmit and receive, it can make up for the boat end to a point.

Look at the available WiFi path calculators and play with the numbers to get a feel for what you might need to do.

[spillemw]

I guess the bandwidth is not going to be your biggest headache, but the QoS is. Video is real-time and packet loss will immediately be "translated" into artefacts on screen or even the image dropping. If the image has to go one way only, meaning from boat to shore, then latency is not going to be an issue, so I wonder if a sattelite link would not be a better idea (internet over sattelite i mean). Another possibility may be to use 4G (LTE) if that is available in the area (although 8 nm out, you may indeed not have coverage).
With regards to antennas, you may want to have a look at this website :
RFS - General Information
They are basically a Alcatel-Lucent reseller. ALU has a very comprehensive set of RF equipment (albeit not cheap).

[evm1024]

For antennas, amps, cables and such I tend to use Ethernet Cable | WiFi Amplifier | Adapter | Wireless | Coaxial | L-com

For amps you can get an outdoor version that has power over the coax. THis allows you to mount the amp next to the antenna. Less loss in the transmit signal and a better signal to noise ratio on the receive signal as that you are not amplifying the noise generated in a long cable run and the weak receive signal from the antenna is boosted before having to run back to the radio card.

In regards to data and remote vs base powers. Don't skimp on the remote side. This is TCP/IP over wireless. There is a lot going on. You could look at a wireless connection as offering a group of services. 802.11 has 9 services and only 3 are used to deliver data. The rest are management services. All of these services are transported by the transmission of a frame of data and the return of an ACK. This is an atomic operation (atomic means that if any part of the operation fails, the whole operation is a failure and is discarded) We really do not need to go to the frame level or even to the packet level. You need good 2-way communications with as few retransmissions as you can manage to achieve.

Regards

[Adamu]

Hi Folks!

So after much deliberation and advice from pros - this looks like what i will be using:

Land based
Ubiquiti RocketM5 27dB radio mounted on 30dB dish.


Boat based
Ubiquiti RocketM5 27dB radio mounted on the Ubiquiti AM5G-16-120 sector antenna
Price each set $ 279.00 ex GST


This should give around 40mb/s data rate over 15km.

Anyone disagree?

Thanks,

Adamu

[EulerTourist]

How did you go with getting this going? Any Pix?