The antenna on your wireless router works on the same principle as your radio or TV. It is just a susceptible to noise and its signal decreases with distance. Because the router antenna ordinary gets signals from anywhere, if all you need to do is receive a signal in only one general direction, you can use a nearby metallic surface that works like a directional antenna. This also has an effect of rejecting noise from interfering sources in other directions causing lower data rates.

But before you go through the effort of using a directional antenna. You might want to first try to avoid obstructed, direct line of sight paths with metallic objects like iron structural beams that are absorbing much of the signal. A lot of times your router antenna is sensitive to just to placement. Maybe the antenna needs to be higher up. There are wifi extenders that are just longer antennas. These sometime work better than using your shorter original antenna because of this placement effect.

You can try out a wireless router booster for as little as $5 by buying a cheap reflector shield that you place next to your antenna. This shield works because it is geometrically shaped like a parabola much like a radio telescope in that it focuses distant waves received to a single point, that being your original 802.11 antenna thus greatly increasing its signal by collecting more rf energy. And, when you transmit at the center of the parabola, it acts to aim the signal in one narrow direction instead of everywhere making it a stronger beam like a flashlight. If you find that this simple boosting technique works with your wireless router, you might want to invest in a directional antenna attachment that does an even better job and is sturdier.

So if you don’t want to do the simple reflector trick you can actually get a powered electronic device that truly boosts the signal. This type of wireless router booster connects to the antenna port and increases the signal as much a 3 times. These may violate FCC laws, but do work. You also have to be careful not to attach such boosters on wifi models with higher-powered ports since these boosters expect a certain low signal level and can burn out if you input too much power. Be aware that such blasting of your router’s signal may cause interference with things that also use the 2.4 GHZ frequency spectrum like cordless phones.

If you have a tough signal zapping situation where, lets say, you need to operate through 2 or 3 concrete walls, you might want to try a work around by getting a Ethernet power line extender. This sends radio frequency data between your computers using your electrical lines and may just to the job for you. Another thing you can try is a repeater. You can buy these devices that extend the range by retransmitting the 802.11 signals. This also causes longer response times because of receive then transmit process. You might be able to configure another wireless router that you already have into a wireless repeater.

Here is a video about building a Parabolic WiFi Booster: