No abstract

It was recently shown that concurrent dualband class-A and -B power amplifiers have a maximum theoretical concurrent-mode (two simultaneous stimuli) drain efficiency of 25% and 62%, respectively, lower than their singlemode counterparts (one stimulus). This paper presents analysis demonstrating that by using current-switching class-D architecture, the concurrent-mode efficiency degradation can be theoretically reduced to zero and a drain efficiency of 100% can be achieved. This theory is then used to design, fabricate, and test a concurrent dual-band current-switching class-D power amplifier operating at 960 MHz and 1.51 GHz. The fabricated PA has a measured concurrent-mode drain efficiency of 46%, which is only 9.6% lower than the low-band single-mode (one stimulus) drain efficiency (55.6%) and only 2.2% lower than the high-band single-mode drain efficiency (48.2%). The corresponding measured concurrent-mode output power is 29.7 dBm, showing only 0.3 dB reduction from the single-mode output power of 30 dBm.

No abstract

No abstract

No abstract