A 3.4-3.6 GHz power amplifier in an InGaP/GaAs HBT
A 3.4-3.6GHz Power amplifier in InGaP-GaAs HBT

This paper presents a 3.4-3.6GHz power amplifier (PA) designed and implemented in InGaP/GaAs HBT technology. By optimizing the off-chip output matching network and designing an extra input-matching circuit on PCB, several problems are resolved, such as resonant frequency point migration, worse matching and lower gain caused by parasitics inside and outside of the chip. Under Vcc=4.3V and Vbias=3.3V, a P1dB of 27.1dBm has been measured at 3.4GHz with a PAE of 25.8%, the 2nd and 3rd harmonics are -64dBc and -51dBc, respectively. Besides, this PA shows a linear gain more than 28dB with S11<-12.4dB and S22<-7.4dB in 3.4-3.6GHz band.