Abstract: A low voltage, switch mode PHEMT power amplifier with a 0.1 ?m gate length and a low loss, lumped element, output matching circuit is disclosed that provides high performance over a frequency range of 1.4 GHz-2.5 GHz. The amplifier makes use of monolithic circuit technology for the first stage and output transistor, and uses a printed circuit board with surface mount components for the output matching network. The power output of the power amplifier is stable over a range of 60 degrees centigrade, has high power efficiencies of 44-53% with greater than 2 watts output power over the frequency range of 1.4 GHz and 2.5 GHz. In addition, through drain voltage control, the output power can be varied over a wide range between about 0.8 to 2.5 watts while still maintaining a high efficiency in the range of 50±3%.

Abstract: A homodyne radar system includes an oscillator, an antenna, a low noise amplifier, a mixing subsystem and a directional coupler. The oscillator is configured to generate a transmit signal and a local oscillator signal. The antenna is configured to transmit the transmit signal and to receive a receive signal. The low noise amplifier is configured to amplify the receive signal. The mixing subsystem is configured to receive and mix the transmit signal and the receive signal to produce an output signal. The directional coupler is coupled to the antenna, the oscillator, the low noise amplifier and the mixing subsystem. The directional coupler is connected and configured to provide a low-loss transmission path from the antenna to the low noise amplifier and a high loss transmission path from the oscillator to the antenna.

Abstract: A low voltage, switch mode PHEMT power amplifier with a 0.1 ?m gate length and a low loss, lumped element, output matching circuit is disclosed that provides high performance over a frequency range of 1.4 GHz-2.5 GHz. The amplifier makes use of monolithic circuit technology for the first stage and output transistor, and uses a printed circuit board with surface mount components for the output matching network. The power output of the power amplifier is stable over a range of 60 degrees centigrade, has high power efficiencies of 44-53% with greater than 2 watts output power over the frequency range of 1.4 GHz and 2.5 GHz. In addition, through drain voltage control, the output power can be varied over a wide range between about 0.8 to 2.5 watts while still maintaining a high efficiency in the range of 50±3%.

Abstract: A homodyne radar system includes an oscillator, an antenna, a low noise amplifier, a mixing subsystem and a directional coupler. The oscillator is configured to generate a transmit signal and a local oscillator signal. The antenna is configured to transmit the transmit signal and to receive a receive signal. The low noise amplifier is configured to amplify the receive signal. The mixing subsystem is configured to receive and mix the transmit signal and the receive signal to produce an output signal. The directional coupler is coupled to the antenna, the oscillator, the low noise amplifier and the mixing subsystem. The directional coupler is connected and configured to provide a low-loss transmission path from the antenna to the low noise amplifier and a high loss transmission path from the oscillator to the antenna.