Long-Distance WiFi Device

[ArmyChief]

Originally Posted by thatboatguy

As for the up to 2km range with an omni I say HA! Try 5 miles +!
George

George, 5 miles + with a omni may possible but, is that staying within the FCC legal realms of multi-point and a maximum EIRP of 1 watt? Then we would also have to consider that the other station has high power/gain system also. There are many factors that would have to be correct to achieve a functional link between you and the other station at 5 miles...

Doug

[colemj]

George,

For clarification, it was Dynamo1181 that made the panty-wad comment and Ronh732 that is the IT professional and discussed omni antenna range. Your post read like you were responding to a single person.

And Ronh732 is correct in that the wifirobin would be a waste of money seeing how easy it is to break WEP encryption without a special device and how few access points and home routers out there are still encoded with WEP.

Mark

[colemj]

Originally Posted by ArmyChief

There are many factors that would have to be correct to achieve a functional link between you and the other station at 5 miles..

Mostly just a good line of sight and proper installation. We regularly get 5 mile connections to small home routers using a device with an omni antenna operating within FCC limits.

Mark

[ArmyChief]

Mark,

Not disagreeing with you..just seems like a typical home router could receive your signal..but would have difficulty trasmitting back to you. Since most home routers are in a room, behind a wall...moreover..most home routers transmit powers ar in teh few hundred milliwatts.

[colemj]

Originally Posted by ArmyChief

Mark,

Not disagreeing with you..just seems like a typical home router could receive your signal..but would have difficulty trasmitting back to you. Since most home routers are in a room, behind a wall...moreover..most home routers transmit powers ar in teh few hundred milliwatts.

Yes, output power isn't everything - receive sensitivity is usually more important. That is why a system with excellent receive capabilities, but lower output will regularly outperform a highly amplified system.

Mark

[ArmyChief]

Mark,

O.k...I agree receive sensitivity is as, if not more importantn...but would you concur that a home router..behind a wall with only 100 mW's output and a great receive sensitivity (which would do nothing to for you when it's transmitting to you) ... would be unlikely to establish a fair if not good link for effective data transmission. I would contend that you would not even pick that unit up..in that circumstance.

[thatboatguy]

Good clarification Mark, I was hoping the shoe would fit where applicable.

And it is right that a lot of things have to line up right to get the 5 miles. A lot of noise on the band will kill it for instance. But then there is usually a better choice closer by in that case. My only objection was to a "professional" proclaiming "up to 2km", when in fact I regularly exceed that.

I've invested a lot of time working out by trial and error some very effective wifi gear for our boat. I'm just tired of engineer types telling me it can't work when most of the posts I've made here were utilizing this gear and some of them were made through 5 miles of air. It's hilarious to hear people then back-paddle and say "well yes, if you have the right gear". The right gear is what this thread is all about!

George

[colemj]

Originally Posted by ArmyChief

Mark,

O.k...I agree receive sensitivity is as, if not more importantn...but would you concur that a home router..behind a wall with only 100 mW's output and a great receive sensitivity (which would do nothing to for you when it's transmitting to you) ... would be unlikely to establish a fair if not good link for effective data transmission. I would contend that you would not even pick that unit up..in that circumstance.

Well, we certainly regularly pick up and use home routers at long distances. I can only assume that they are located inside the house.

[ArmyChief]

LOl..ok Mark..we'll agree it's possible and that people are doing it everyday. We'll just leave it "open" to the Hot Spots location, equipment type, antenna type, atmospheric conditions, sun spots, multipath distortions caused by water...etc...etc

Please take this as the jest it is meant.....

[simonmd]

Originally Posted by Dynamo1181

Anyone used or heard of the success of a person using the WifiRobin? Also, which antenna was used with the unit?
thx
A

Sent you a PM.

Open discussion of these devices may get the forum into trouble as they are 'technicaly' illegal, so best kept private.

[Viking Sailor]

At the WIFI frequencies the sensitivity of the receiver is determined by the thermal noise generated by the first RF amplifier. This thermal noise is a result of the design and implementation of the RF amplifier.

RF equipment designers know that in a two-way system increasing just the transmitters RF output will not improve the link. It takes a similar decrease in the receiver's noise floor to balance the link. So, to increase the range on a link where one station has a 100 mw transmitter and a receiver with a-100 dbm noise floor by increasing the second station output to 800 mw (+9 db) would also require the second receiver to have a -109 dbm noise floor to balance the link.

It is interesting to note that an antenna with gain increases both the effective radiated power and the effective received power. This increase in effective received power can move a received signal from below (unreadable) to above (readable) the noise floor. Thus, an antenna with 9 dbi of gain connected to an AP with a 100 mw transmitter and a -100 dbm receiver, would be the same as having a 400 mw transmitter and -106 dbm receiver connect to a 3 dbi antenna.

[callmecrazy]

Originally Posted by thatboatguy

Cool beans, I'll be interested to know how you like it. BTW I have had one very bad experience with that seller myself. I finally got a full refund but I should not have had to fight for it.

George

Well I've been using this for over a month now and I can say I'm very happy with it. I've only been in two different marinas though, no anchorages. Both marinas did not offer wifi, so I've been using unsecured networks from neighboring homes.... In both cases I now get a full signal where without it I'd either have no network available or a signal too weak to be usable. Full speed Internet with this thing bungied to the boom I'm happy.

It's already weathered several heavy downpours, but I took it down for irene. I was able to get a good signal even with it just propped up in a window at the old marina, but where I'm at now I need to point it in a better direction, so it sits on the boom.

I have no idea how far away these networks are, but its a 1.5w radio and directional, so it should be fine at anchor in a populated area...

I ended up buying from that seller despite his incorrect description. It was the best price and I'm cheap it shipped quickly and I had no problems.

For a $40 plug and play device that's powerful enough and weather proof, I don't think it can be beat

[DotDun]

Originally Posted by colemj

Mostly just a good line of sight and proper installation. We regularly get 5 mile connections to small home routers using a device with an omni antenna operating within FCC limits.

Mark

I'm curious how you're measuring the distance?

[colemj]

Originally Posted by DotDun

I'm curious how you're measuring the distance?

Most of the time when I estimate the distance, it is to the closest habitable piece of land from where we are anchored.

Mark

[thatboatguy]

Originally Posted by callmecrazy

For a $40 plug and play device that's powerful enough and weather proof, I don't think it can be beat

Hey David,

Thanks for the update but can you remind me what the device is again? heh heh I have been so deep into this engine rebuild, hurricane, and monsoon weather that I have neglected my wifi projects.

George

P.S. We might overtake you on our way south if you don't run fast!