Nautical WiFi challenge

[JonH]

The marina I sail from has WiFi but picking up a workable signal on my Dell laptop (with built-in WiFi) is a waste of time. This is not surprising because the main ISP aerial is 70m away, there are metal masts obstructing the signal and the internal aerial on the laptop is probably crowed out by the rest of the laptop electronics.

The marina WiFi ISP recommends an external WiFi receiver but boat owners nearby report they have to hang this device up externally and trial a wire down below.

I have an alternative plan but I need to pick the brains of some experts here.

I want to buy some type of WiFi extender that will run off the boats 12v supply. This will be placed in a tupperware box and hoisted about 15ft up one of the mast support wires.

What I need is a WiFi receiver/transmitter that will log into the ISP as though is was my laptop and then re-transmit a WiFi transmission down to my laptop through the cabin roof. Does such a device exist?

p.s. I want to avoid a wired Ethernet solution because this would entail running power and Cat5 cables part way up the mast, then I would need run the ethernet cable through to the chart table requiring drilling holes in bulkheads and 2nd watertight deck plug.

[marky]

I'm no expert, but you can buy linear amplifiers (like they use on cb's) which do it both ways (suck and blow)
But i dont know if that sort of thing would do the frequency required

[Stuart]

One way to do it would be to use a wrt54G mounted in a weatherproof casing (look at the top article on http://www.dd-wrt.org for an example). You can then set that up (using the instructions at http://forum.bsr-clan.de/viewtopic.php?p=32519 ) to rebroadcast the Wifi signal to another router inside the boat.

[JonH]

Originally Posted by Stuart C

You can then set that up (using the instructions at http://forum.bsr-clan.de/viewtopic.php?p=32519 ) to rebroadcast the Wifi signal to another router inside the boat.

Thanks Stuart, I followed this link but the discussion does not match my objective exactly.

The thread at bsr-clan.de covers this:
Master AP[DHCP SERVER] (on the net)=====wifi=======Client---wired-----AP[DHCP SERVER]=====wifi====other clients

Whereas this is what I want to achieve:

[Main Marina AP]<== wifi ==>[Combined Client/AP up mast]<== wifi ==>
[Dell laptop in cabin with internal WiFi card]

Maybe my only option is:

[Main Marina AP]<=== wifi ===>[Client WRT54 upmast]
<-- short ethernet link --->[Router/AP WRT54 also upmast]
<=== wifi ===>[Dell laptop in cabin with internal WiFi card]