Microwaves are the electromagnetic waves that lie in the frequency band 300 MHz to 300 GHz. The wavelength range of the microwaves lies between 1 metre to 1 millimetre. In the electromagnetic spectrum, the microwaves are located between radio waves and infrared waves. Microwaves are advantageous as they consist of a large bandwidth that allows easy transmission of bulk data. Also, microwaves rarely get affected by the sky noise.
Examples of Microwaves
1. Ovens
One of the major applications of microwaves can be seen in the kitchen appliances such as a microwave oven. The magnetron present in the internal circuitry of the microwave oven emits microwaves. These emitted radiations get reflected on striking a metallic surface and get absorbed by the food particles. This property of microwaves is utilized to heat and cook food.
2. GPS
The operation and working of a GPS or a global positioning system are based on microwaves. A global positioning system consists of a network of satellites that communicates with the receivers present on the earth by constantly radiating microwaves. The receivers then make use of the ranging method to track down an unknown location. Microwaves travel at the speed of light. Hence, the velocity with which the wave travels is well known. Also, the time taken by transmitted radiations to reach the receiver can be noted easily with the help of timing devices. This is the reason why locating a particular place with the help of a GPS is precise and accurate.
3. Wi-Fi
Wi-Fi is the acronym for wireless fidelity. Typically, a Wi-Fi network works at 2.4GHz and 5GHz frequencies. Both the frequencies fall under the category of microwaves. For instance, the signals by laptop wifi are transmitted at 2.4 GHz, which falls in the frequency band of microwaves. Hence, Wi-Fi is a technology that makes use of microwaves for the transmission and reception of signals.
4. Bluetooth
Bluetooth is a wireless communication protocol that allows multiple devices to exchange information amongst each other simultaneously. It works at 2.4 GHz frequency. All the frequencies lying within the range of 300 MHz to 300 GHz comprise the microwaves. Hence, Bluetooth technology makes use of microwaves for its operation.
5. RADAR
RADAR or radio detection and ranging makes use of microwaves to locate an obstacle. Microwaves can easily propagate through space and the atmosphere. This property of the microwaves helps to determine the shape and locate the exact position of an obstacle. The microwaves emitted from a transmitting antenna are directed towards the target. On striking the target object, a part of the energy gets reflected, thereby providing information about the obstacle.
A microwave RADAR sensor
6. Communication Systems
Microwaves are used in a number of communication techniques such as satellite communication, cellular communication, point-to-point communication, spacecraft communication, wireless communication, optical communication, etc. This is because the high frequency and the ability to propagate at the speed of light enables the microwaves to transmit signal over long distances with minimal loss or distortion.
7. Medical Equipment
A number of medicinal applications make use of microwaves. For example, the heating ability of a microwave is used to dry human tissues for medical purposes, the high frequency of the microwaves can be utilized for the surface-based treatment of diseases, etc. Also, microwaves play a huge role in curing cancer, vision correction, vein therapy, and treatment of many other diseases.
8. Weapons and Military Equipment
Microwaves are used in the construction of directed energy microwave weapons used by the military. As the name suggests, these types of weapons make use of high-frequency microwaves. The high power possessed by such waves is focused or directed towards the target that demolishes the target. A cloud of high power microwaves is formed in the air that helps to destroy the enemy drones. The advantage of using microwaves in military equipment is that they do not get affected by bad weather.
Directed energy microwave weapons
9. Astronomical and Space Exploration
Microwaves play a very important role in space exploration. They are used in satellite-based telescopes to get a better view of the earth. The microwaves possess the ability to propagate through rain, fog, storm, clouds, and other peculiar weather conditions. This advantage of a microwave helps to elevate the experience of studying astronomy.
10. Commercial and Industrial Application
Microwaves are used in a number of industries such as the food industry, communication industry, medical industry, etc. Microwaves are high energy waves that can heat or melt an object with ease. This is the reason why one of the major uses of microwaves lies in industrial heating. Microwaves are also used in rotational spectroscopy.
A microwave industrial heating system