| 摘要 |
<p>A branched power amplifier circuit includes two or more amplifier segments or branches, each with a corresponding lossy modulator. The branched power amplifier may be dynamically resized by enabling different ones of its branches to deliver peak efficiency at a number of different amplifier output power levels. Each amplifier branch operates in a saturated mode and selectively amplifies an RF input signal. The lossy modulators provide either supply voltage or supply current modulation to corresponding amplifier branches, thus imparting highly linear amplitude modulation to the overall output signal generated by branched power amplifier, despite its saturated mode operation. The branched power amplifier circuit may be configured such that particular combinations of segments have peak efficiencies matched to the needs of one or more air interface standards used in wireless mobile communication systems.</p> |
