Can I use an extension cable with universal dongle?

I am planning to buy a universal dongle (most probably D-Link) for mobile broadband access so that I can use it with any service providers. But I am not sure if I can use an extension cable in a universal dongle. I think by using an extension cable I can have a better coverage in areas where network coverage is poor. If this is possible, is there any limit on the length of cable to be used?

buy a wifi enabled dongle. then you can put it anywhere, attached to a battery pack.

Originally Posted by panchabhut

buy a wifi enabled dongle. then you can put it anywhere, attached to a battery pack.

That is true and it can cover 10 meters or so I think. I am particularly interested in Huawei E8221, heard that it works well as a WiFi 3G dongle. It is factory unlocked and I can use any SIM with it. I think this is the model which I am looking for. But the sad part is that it is not available in most of the retail outlets. They have D-Link WiFi dongles, but not Huawei. I don't think why Huawei is not popular here.

I think as a last resort I need to got online for purchasing this model. Amazon got a good deal on this. They charge something near Rs.1600/- without a USB adapter. eBay charges more than Rs.1800/- for this.

I bought my E8221 from Amazon @ 1499 in Lightning deal. keep looking. its often available at that price. Also instead of directly buying, first load money in gift card and then buy using gift card. Gift cards are regularly available @ 5% discount. So effective cost would be even less.