{http://www.hyperlinktech.com/web/copyrighted_images/hg2417p.jpg panel}

Panel [Antenna] are similar to cell tower antenna. They typically have coverage of 60-180 degrees.

Gain typically range from ? to 20dbi

They are usually very expensive, but you can [HomeBrew] one fairly easily.

There are [HomeBrew] details you can follow (http://www.saunalahti.fi/~elepal/antenna1.html on the net).