GaN on SiC-based RF transistor targets secondary surveillance radar aviation applications

August 31, 2012 // By Paul Buckley
Microsemi Corporation has released the first in a family of RF transistors for high-power air traffic control (ATC), secondary surveillance radar (SSR) applications.

SSR is used to send a message to an aircraft equipped with a radar transponder and collect information that allows air traffic controllers to identify, track and measure the location of that particular airplane.

The 700 W peak 1011GN-700ELM operates at 1030 MHz and supports short- and long-pulsed extended length message (ELM). The transistor is based on gallium nitride (GaN) on silicon carbide (SiC) technologies, which are particularly well-suited for high-power electronics applications.

"We are aggressively driving the development of next-generation GaN on SiC power devices to address growing opportunities for higher performance aerospace and military applications," said David Hall, vice president of Microsemi's RF Integrated Systems product group. "With today's new product introduction, we now offer highly reliable GaN on SiC transistors at 250, 500 and 700 W for secondary surveillance radar search and tracking applications. We also have several additional GaN on SiC transistors in development that we will be rolling out later this year."

Microsemi's upcoming product lineup includes multiple high-pulsed power GaN on SiC transistors for both L, S and C-band radar systems. The company also offers a suite of GaN microwave power devices, which includes the following S-band radar models: 2729GN-150, 2729GN-270, 2731GN-110M, 2731GN-200M, 3135GN-100M, 3135GN-170M, 2735GN-35M and 2735GN-100M.

Several new products are in development for L-band avionics products covering 960 to 1215 MHz; L-band radar covering 1200 to 1400 MHz; and S-band radar, higher power devices covering 2.7 to 2.9 GHz.

The 1011GN-700ELM transistor delivers performance of 700 W of peak power with 21 decibel (dB) of power gain and 70 percent drain efficiency at 1030 MHz to improve reduce overall drain current and heat dissipation.

Systems benefits that are achieved with GaN on SiC high electron mobility transistor (HEMT) includes a single-ended design with simplified impedance matching, replacing lower power devices that require additional levels of combining. The technology claims to deliver the highest peak power and power gain for reduced system power