Mixed-signal Active Load-pull System Breaks the 500 W Barrier
Maury Microwave, in conjunction with Anteverta-mw and NXP Semiconductors, has successfully characterized a NXP 8th generation LDMOS 320 W-rated base station transistor up to 500 W using the fully active MT2000 mixed-signal active load pull system (MSALP).
This base station transistor was measured at 2.14 GHz, in a pulsed-CW condition with pulse width of 50 µS, duty cycle of 10 percent, using a prematch transformer test fixture at 7 Ω. The power amplifier used to drive this DUT up to Pout=500 W and down to 1.5 Ω was a 500 W NXP Doherty amplifier demo board, an almost 1:1 relationship with the device output power. A maximum output power of 470 W and a maximum efficiency of 62 percent were measured at 3 dB gain compression.
The MT2000 mixed-signal fully active load pull system represents the next evolution in device characterization systems, capable of presenting impedances below 0.05 Ω (Γ=1, VSWR>999:1), unique in its capability of measuring up to 1000 impedance/power states per minute, and unique in its capability of up to 120 MHz of instantaneous wideband impedance control for industry-compliant and proprietary wideband modulated signals.