Need Automotive WiFi Repeater for Automatic Roaming - to extend range of laptop with no antenna connector
Posted on 2006-05-18
I am about to embark on a tornado chasing adventure in the US heartland. I have a Dell laptop with internal WiFi only. I need to be able to detect and operate with WiFi AP's by using a good external antenna, but without physically attaching the antenna cable to the laptop.
Thus I want ithe ability to use a black box to repeat communications between my laptop's internal card and ANY network I run across - i.e. a repeater, but with special characteristics. From a functional standpoint, the solution would be invisible to the laptop - it would see the same network universe as it sees now but with better coverage - and would then be able to connect to one I choose. Being required to configure the digital 802.11 repeater before I could even see a network would probably not be acceptable.
There are three reasons for not wanting the physical connection:
1) There is no antenna connector on the laptop - I would have to use one of my PCMCIA slots with another adapter
card to even be able to do this.
2) Microwave connectors of the size for this applicaiton are very fragile, and I have already broken one in cell phone use.
3) The fewer physical connections to the laptop, the better. It needs to be able to quickly go from car to, let's say, truck stop restaurant and back without disconnecting and connecting a myriad of cables. Note that a repeater in such a situation would also give me extended coverage from anywhere near my car, such as a restaurant.
Approaches I have thought about that might be acceptable if certain conditions are met:
1) Get a commercial digital WiFi repeater and configure it for the roaming capability. I know there are repeaters, or AP's or routers that can be configured as repeaters. I DON'T KNOW if they have to be configured to a network before they can repeat it.
2) Use an "open" WiFi router such as the 54G and hack it to do this. I don't really have time for much hacking (although I have written considerable low level network code in the past), but if someone knows of an existing hack that would do the job.
3)Make a digital repeater from a second computer, with two WiFi cards and appropriate software or configuraiton. I have seen discussion of bridging using XP, but don't know if it will meet my roaming requirements. This has cost considerations and still might not meet my roaming requirements.
4)Use a two-way RF amplifier with a gain antenna on the roof and a little antenna in the car. An iin-car two-way amplifier (from Wilson) might relay the raw RF signals between the in-car environment and a high gain rooftop antenna. However, I don't know if they cover the 2.4 GHz band, and they also have problems with weak signal areas. These things do exist for cell/PCS phones, which is how I found them. Technically, the weak signal area problem is because two-way amplifiers are inherently limited by the near proximity of the amplifier antenna and the device inside the car - they tend to be more appropriate for situations where the signal is at least moderately strong outside the vehicle but weak inside - attenuated by the lousy antenna on the phone or WiFi card and the metal parts of the car body. In general, a digital repeater (options 1-3) would have probably significantly better range than the 2-way RF amp approach.
5) ??? Any other ideas?