Role of Radar in Microwaves

IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES

Merrill Skolnik, Life Fellow, IEEE

Falak Shah 09bec082 Nisarg Shah 09bec084 Guided by Dr. Dhaval Pujara

Flow of contents

• Central Idea• Early Developments• What happened during world War II• Applications• Microwaves In Modern Radar• Possible Future Directions For Radar

Central Idea :Interdependence

Microwaves Radar

1880-Hertz Experiment

• Maxwell theoretically proved EM waves exist

• 1880, Heinrich Hertz- first radar scientist experimentally proved

• 450 MHz microwaves fed to dipole

• Followed by JC Bose 60-120 GHz

1939-Varian brothers Klystron

• Predecessor of magnetron by Varian brothers of Stanford University

• Most important high power radar application device also frequency controllable.

1940-Magnetron

• 1930 radar concept given theoretically

• Need of high power stransmitter

• High frequency radar (3 GHz) for detecting smaller objects

• Limitation of high power overcome by magnetron

• Frequency depends on dimensions of cavity

What happened during World War-II

• 1940-setup of MIT radiation lab for research on application of magnetron for radar.

• 4000 personnel aged 20-30 gathered & gained expertise on 100 different radar equipments

• Allies gained upper hand over axis powers• Radar was evolved much faster when placed

into civilian hands than controlled by military • Today, TWT which is variant of klystron widely

used

Other applicationsWeather Radar at Oklahoma Ground penetrating Radar

-Seahawk Navigation

Other ApplicationsSpeed measurement Sea Ice Mapping

Microwaves In Modern Radar

• Digital signal processing• Differentiate between more than one target• Transmitters The klystron is a good choice for high-power

applications, with the TWT (Travelling Wave Tube) as a candidate when wide bandwidth is needed.

Phased Array Radar

• Phase array antenna is used in advance radars now a days.

• This can form various directional patterns and provide varying directivity.

• An advantage of a phased array is its ability to perform multiple functions such as surveillance and weapon control with a single system.

TWT

Possible Future Directions For Radar

• Developing Jammer Technologies• Radar Sea Echo• Phased array with fixed beams (Ubiquitous)• Millimetre wave radar

THANK YOU