JSSC 2008第10期Digital CircuitsGaAsPower AmplifierNeural Network Accelerator

250 W HVHBT Doherty With 57% WCDMA Efﬁciency Linearized to 55 dBc for 2c11 6.5 dB PAR

采用HVHBT GaAs技术的250W对称Doherty放大器，实现57%效率和55dBc线性化ACPR。

250W饱和功率，57%效率，55dBc ACPR，28V偏置

HVHBTDoherty放大器高效率线性化WCDMA

▸创新点1：高压HBT（HVHBT）GaAs技术，采用28V集电极偏置，显著提升功率放大器的饱和功率至250W，同时保持高效率（>57%）和高线性度（55 dBc ACPR）。

▸创新点2：对称Doherty放大器设计，通过两路对称结构实现高效功率分配与合成，在50W平均输出功率下达到57%的集电极效率，显著提升系统性能。

▸创新点3：低损耗分支线合路器，用于450W峰值功率系统的功率合成，确保高效率（44% PAE）和高增益（25 dB），同时保持优异的线性度（55 dBc ACPR）。

▸创新点4：两级HVHBT功率放大器系统，结合250W Doherty放大器和100W AB类放大器，实现400W连续波输出功率下60%的PAE，并在6dB回退时保持45%的PAE。

Abstract

A two-way symmetrical Doherty ampliﬁer exhibiting 250 W saturated power has been developed using high-voltage HBT (HVHBT) GaAs technology biased at 28 V on the collector. Greater than 57% collector efﬁciency at 50 W (47 dBm) average output power has been demonstrated while achieving 55 dBc linearized ACPR at 5 MHz offset using a two-carrier-side-by-side WCDMA input signal with 6.5 dB PAR measured at 0.01% probability on the CCDF. In addition, a two-stage HVHBT lineup exhibiting 450 W (56.5 dBm) peak power has been demonstrated. The output stage consists of a pair of 250 W two-way symmetrical Doherty ampli- ﬁers power combined using a low-loss branchline combiner and driven by a single-ended 100 W class AB high-efﬁciency ampliﬁer. The lineup demonstrated 44% PAE at 100 W (50 dBm) average output power with 25 dB lineup gain while achieving 55 dBc linearized ACPR at 5 MHz offset using a two-carrier-side-by-side WCDMA input signal with 6.5 dB PAR measured at 0.01% prob- ability on the CCDF. The lineup exhibits 400 W (56 dBm) /80/49/100/66 at 60% PAE CW, with 45% PAE at 6 dB backoff.