Fujitsu Labs has developed a record breaking GaN high-electron mobility transistor (HEMT) amplifier for C-Ku Band radar.
"It features an output of 12.9W, more than twice the output of previous amplifiers when operating in the C-band, X-band, and Ku-band spectrums between 6GHz and 18GHz," said the lab.
Aircraft radar typically switches between the C-band, which is relatively unaffected by rain, according to Fujitsu, and the X- and Ku-bands which offer precision detection of solid objects.
"An amplifier featuring the ability to cover the entire range of the C- to Ku-bands on its own would allow for smaller systems that consume less power," said Fujitsu. "This has led to keen interest in multifunctional radars which integrate communications systems and multiple radars and into a single device."
To amplify large parts of the spectrum, multiple transistors are generally connected in parallel, however, as the circuit is physically long, line loss mean that it is difficult to extend coverage up to 18GHz.
Fujitsu has devised a band extension circuit that compensates line losses at high frequencies, and an integrated wideband power dividing and combining circuit.
The result is 6-18GHz operation at 18% efficiency.
Details of this technology will be presented at the IEEE MTT International Microwave Symposium (IMS 2010) in Anaheim this week.
