Q: What is the importance of antenna in a wireless communication system?
A: Antenna works as transformer, it has two modes of operation as Transmitter and as a Receiver. In transmission mode, the antenna transform the electrical signal guided by the wire or (wave guide) into a propagating free space wave. In reception mode, it does the reverse process, it captures the electromagnetic wave and transform it to electrical signal.

Q: What's best high gain wifi antenna?
A: Some of the most powerful antennas are the 30 dbi grid, and then for even more dbi, the dish antennas are really good. I'm making a homemade wifi dish antenna from an old satellite dish, lots of fun.

Use a low loss cable to connect your antenna and keep it as short as possible. Wifi signals really degrade over cable. For example, if you have 20 feet of cable, you may lose half your antenna dbi just from the cable.
If you want to use backtrack, you will need a wifi card that supports monitor mode and packet injection. Look for something with an Atheros chip that is supported by madwifi, and has at least 200mw power.

The cantenna is a directional antenna, so it only works in the direction that it is pointed. Your router antenna is omni-directional antenna, and so it works in all directions. The two have completely different applications.

Q: How Do I Choose the Best Mobile Antenna?
A: A mobile antenna is a type of antenna that generally gives adequate signal even when one is on the road. There are several variables to consider when choosing the best mobile antenna. These variables include the places where you live, where you work, and where you visit regularly, along with your geographical location, and the available frequencies operating in the area. Knowing the various kinds of mobile antennas, and how they are mounted can also help you make your choice. Other things to consider are your budget and your technical skills in setting up the antenna.

When choosing a mobile antenna that matches your needs, it is usually advantageous to first determine what kind of environment your antenna will be dealing with. You can try looking around the area surrounding your home, your workplace, and the places you regularly visit. These are places where you will more than likely use your mobile antenna. It is often advisable to take note of the layout of the place and obstructions present in these places. By doing this, you can narrow down your search to a few specific types of antennas.

There are various kinds of mobile antennas. These include the portable ones, the hidden ones, and the mounted ones. If you prefer a hidden antenna, you can choose one that matches your needs. Mounted antennas can be mounted on top of your vehicle, on the glass, or in a movable base. Some mobile antennas work best when they are mounted and reach a considerable height, while others may work well when hidden.

Aside from portability and convenience, you also need to select the mobile antenna that can adapt well with your surroundings wherever you go. An antenna that can change bands and frequencies without requiring too much effort from you is often a good choice, especially when you are looking for a car antenna. A remote-controlled mobile antenna is another one you can select. This is frequently a better choice if you drive around a lot and if you do not have time to stop and re-adjust your antenna in order to change frequencies. A convenient mobile antenna that does not require a lot of maintenance while on the road is generally the best choice.

It is also necessary to choose an antenna that matches your budget requirements. Asking more experienced individuals about your specific antenna needs can often guide you in choosing the right antenna that is well within your budget. The installation of your chosen antenna may also require some skills in electronics and in handling different kinds of construction hardware. You can choose to do the installation or you can ask someone with technical skills to do the installation for a certain fee.