High performance S-band transistors for radar and communications

Recent technological improvements have led to increased performance in prototype silicon bipolar transistors for S-band operation. These transistors may find application in both long and short pulse radars and CW communications links. Over 30 watts long pulse has been obtained with greater than 10 dB gain and 43 percent collector efficiency in the 3.1 to 3.5 GHz radar band and over 50 watts has been obtained at 2.7 GHz with short pulse operation. More than 10 watts has been obtained under CW conditions at 4 GHz with greater than 8 dB gain and 40 percent efficiency. The pulse device has significantly greater performance than the best reported GaAs devices in this band.