An X/Ku Dual-Band Switchless Frequency Reconfigurable GaAs Power Amplifier

This letter presents an
$X$
/
Ku
dual-band switchless power amplifier (PA) with frequency reconfigurable operation in a 0.25-
$\mu \text{m}$
GaAs pHEMT process. The proposed reconfigurable PA consists of one dual-band drive amplifier and two single-band amplifiers in parallel. The first stage drive amplifier works in dual-band mode of
$X$
-band and
Ku
-band, and the two single-band amplifiers work in
$X$
-band and
Ku
-band, respectively. An interstage coupled line is used to split the dual-band frequencies into high-band (
Ku
-band) and low-band (
$X$
-band), and the output-stage coupled line acts as a combiner. The operating frequency band of the proposed PA can be changed by turning off drain voltages of unused single-band amplifiers. Measurements results show that the proposed reconfigurable PA features a maximum power-added efficiency (PAE) of 44.4% and a power gain of 19.6 dB while delivering an output power of 29.6 dBm at 8.5–9.5 GHz of the low-band mode. At 15.5–16.5 GHz of the high-band mode, the PA achieves a maximum PAE of 38.4%, a power gain of 18.1 dB with an output power of 30.1 dBm. The chip area of the proposed reconfigurable PA is 2
$\times $
2 mm
²
including all RF and dc pads.