A sector antenna is usually a directional microwave antenna whose radiation pattern has a sector-shaped output waveform. The term "Sector" is used in the geographical sense; a definite portion of a circle measured in degrees is considered to be sector. That is, any portion that touches the diameter of the circle is considered to be Sector.
The use of sector antennas is widely used for many purposes, including receiving radio signals. The most common and simple form of a sector antenna is its shape itself - a short antenna with two antennas on each side and a center antenna. In order to receive or emit radio waves, such antennas must be positioned in a way that will give them a clear view of both sides of the sky. The reception of signals from the earth and the moon is easy; however, it becomes a bit more complicated when the signals have to travel through clouds, rain or even snow. Clouds block up the sunlight and reduce the strength of the signal. Snow and rain interfere with the signal strength. This is why WiFi equipment operates best in sunny areas. And if a signal cannot be received from the moon, the only other option is to mount your Sector Antenna on the International Space Station or on a rotating satellite which would give you a better and stronger signal.
Sector antennas are used for a variety of purposes. As mentioned above, they are used to send and receive radio signals in a straight line. They are also used for radar detection in air, water or even on land. Usually, the antennas used for such purposes have a combined output of a high-frequency (high frequency) and low-frequency (low frequency) antenna. However, one aspect of using a Sector Antenna in aviation is the possibility of it receiving strong electromagnetic radiation from other aircraft. Some of the aircraft in the skies belong to the category of commercial airliners and are not bound by the set guidelines imposed by the Federal Aviation Administration. They can fly over certain parts of America and even in some Asian countries without following the set guidelines. Thus, a radar detecting antenna would need to be specially made for such flying purposes.
These antennas can be used to detect such radiation patterns. A low-frequency antenna can detect the radiation pattern, while a high-frequency antenna can pick it up. In most cases, a low-frequency antenna can be mounted on the outside of the aircraft while a high-frequency antenna can be mounted in a nose-up position. Thus, a sector antenna could detect low-frequency radiation and a high-frequency antenna could detect high-frequency radiation. However, both antennas would have a hard time penetrating clouds. The sensitivity of the particular Antenna depends on its frequency and the distance at which it has to operate from. A low-frequency Sector Antenna has the minimum range that it can work in. It works just fine in cloud cover or at minimum distances from nearby skyscrapers. However, if the Antenna has a higher bandwidth, it will be able to detect stronger radiation patterns. Hence, a good example of a high-frequency Sector antenna is the one that is placed on top of an aircraft.
It is very important to know how much coverage area the Antenna has before buying it. This is because there are many antennas with low-level of output power. Often, such Sector Antennas gives better performance when they are used for covering smaller areas. On the other hand, such low-powered Sector antennas are not good for covering large areas. If you need the best performance from your antenna, you should buy one that has a power output capacity that will suit the size and type of your installation.