Phased Array Radar: Pros, Cons & Makers

Introduction : We have seen massive curved mechanical dish rotating on pedestal and sweeping the sky with radio beam. While effective, this mechanical dish is limited by physics. It can only look in one direction at a time and its sweep speed is restricted by how fast a heavy motor can spin it.

Phased Array Radar (PAR) has eliminated motors and replaced single dish with grid of hundreds or thousands of microscopic antennas. Moreover PAR steers radar beam entirely using electronics.

Now-a-days, Active Electronically Scanned Array (AESA) phased array technology is the absolute standard for modern fighter jets, naval destroyers, ballistic missile defense and satellite tracking.

How Phased Array Radar Works ?

A phased array radar consists of a flat panel populated by hundreds or thousands of individual radiating antenna elements. Behind each antenna is a Transmit/Receive (T/R) module that can independently control timing (i.e. phase) and power (i.e. amplitude) of radio wave it emits. When all the antennas fire at the exact same time, the wave moves straight forward.

Because this steering is entirely electronic, a phased array can move its radar beam from one side of the sky to the other at the speed of light.

Key benefits of Phased Array Radar (PAR)

Following are some of the advantages of PAR radar.

1. A mechanical radar takes several seconds to complete a 360 degree sweep. A phased array can shift its beam from one target to another in microseconds.
2. Because the beam can move so fast, a phased array can effectively do multiple things at once. Hence it can be used for Multi-Target Tracking and Multi-Functionality applications.
3. Mechanical radars have a single point of failure such as motor or central transmitter. In AESA radar, as there are thousands of independent modules, there is a chance that radar does not stop working when some modules are burnt out.
4. As they are flat, phased array panels can be seamlessly integrated into the angled fuselage of a stealth fighter or the superstructure of a naval destroyer. This eliminates radar cross section (RCS) of spinning dish, making the craft much harder for the enemy to detect.

Limitations/Challenges

While vastly superior to mechanical radar, AESA systems present following challenges.

1. AESA radar generates immense amount of heat. Hence it requires highly complex, heavy and expensive liquid cooling systems.
2. AESA radars are incredibly expensive.
3. To generate the raw RF power needed to see targets hundreds of miles away, AESA radars draw massive amounts of electricity.
4. Controlling thousands of independent antennas requires supercomputer level digital processing. Moreover advanced level of software and AI are needed to keep beam focused. Hence this leads to software and calibration complexity.

Key manufacturers of Phased Array Radars

Summary:

Phased Array Radars (AESA) replace traditional mechanical dishes with flat, electronically steered panels, offering instantaneous multi-target tracking, high reliability and low observable stealth capabilities. The PAR radar market is dominated by prime defense contractors like RTX, Lockheed Martin, and Northrop Grumman, who rely on critical RF components from innovators like ADI and Qorvo.