CIVIL APPLICATIONS OF MICROWAVE

Daryl Pongcol

Outline

Major Civil Applications Communications Radar Radio Astronomy

Other Applications of Microwave Microwave Heating Wireless Power Transmission

Major Civil Applications

Major Civil Applications

Communications Most long-distance telephone calls were

carried via networks of microwave radio relay links run by carriers [PLDT, Bayantel, SMART, Globe]. The addition of FDM boosted the communication for up to 5400 telephone channels for distances of up to 70km away.

Microwave Radio is used in broadcasting and telecommunication transmission because, due to their short wavelength, wide bandwidth, highly directional antennas are smaller and therefore more practical.

Major Civil Applications

Communications IEEE Communication Protocols makes use of the

frequency bands under the microwave spectrum: IEEE 802.11 - set of standards for implementing

Wireless Local Area Network (WLAN) computer communication. [examples: bluetooth, wi-fi]

IEEE 802.16 - standards for Wireless Broadband Technologies. [examples: Wireless Modems, WiMAX]

IEEE 802.20 - standards for Mobile Broadband Wireless Access (MBWA) communication. [examples: cell phones]

Major Civil Applications

Communications Most satellite communications systems

operate in the C, X, Ka, or Ku bands of the microwave spectrum. These frequencies allow large bandwidth while avoiding the crowded UHF frequencies and staying below the atmospheric absorption of EHF frequencies.

Major Civil Applications

Radar Radar uses microwave radiation to detect the

range, speed, and other characteristics of remote objects. Development of radar was accelerated during World War II due to its great military utility. Now radar is widely used for applications such as air traffic control, weather forecasting, navigation of ships, and speed limit enforcement.

Major Civil Applications

Radio Astronomy Most radio astronomy uses microwaves.

Usually the naturally-occurring microwave radiation is observed, but active radar experiments have also been done with objects in the solar system, such as determining the distance to the Moon or mapping the invisible surface of Venus through cloud cover.

Other Applications

Other Applications

Microwave Heating To the average consumer, the term

"microwave" is more popular in the kitchen rather than in any of the sophisticated communication technologies outside the kitchen. A microwave oven:

 

Other Applications

Microwave Heating The principle:

This thing works by passing non-ionizing microwave radiation, usually at a frequency of 2.45 GHz through the food. Water, fat, and other substances in the food absorbs energy from the microwaves in a process called dielectric heating.

Other Applications

Wireless Power Transmission One good thing about Microwave Systems is its characteristic of

being a point-to-point communication medium. As what we've been hearing throughout this course, microwave systems transmit energies through microwave beams. In this way, the idea of power transmission over large distances has already been proposed. One example is the solar satellite power station, where it

has been proposed that electricity be generated in space by a large orbiting array of solar cells, and transmitted to a receiving station on earth by a microwave beam. We would thus be provided with a virtually inexhaustible source of electricity. Placing the solar arrays in space has the advantage of power delivery uninterrupted by darkness, clouds, or precipitation, which are problems encountered with earth-based solar arrays…

…MAO RA!

selemet!