Date Added: Mar 2010
As expensive and inconvenient as wires may be, when it comes to transmitting data, they are generally quite reliable. Once working, they tend to stay working, offering the same steady performance level until someone cuts them, unplugs them or digs them up. However, modulated electromagnetic waves propagating in free-space (aka radio waves or Wi-Fi signals), are anything but steady. They interact with the environment through exotic physical mechanisms such as reflection, refraction, fast fading, slow fading, attenuation and ducting. Even with the best wireless protocols, the best chipsets, the best RF design, the best software and the smartest antennas, wireless performance is going to vary - and it may vary a lot.