A multi-mode multi-band power amplifier for quad-band GSM, dual-band TD-SCDMA, and TDD LTE band 39 cellular applications

A novel multi-band multi-mode (MMMB) power amplifier (PA) structure for GSM/TD-SCDMA/LTE cellular applications, is presented. For good harmonic suppression and high integration density performance, a Class-E PA and linear PA cores are employed with only two output paths for low band (LB) and high band (HB), respectively. The selections of modes (2G/2.5G/3G/4G) and working condition of each PA core are controlled by a commercial CMOS controller. The selection of output paths are controlled by a low-loss radio frequency switch (RFSW) within a directional coupler for good linearity and efficiency. To demonstrate the feasibility of the concept, the PA was tested under a series of discrete frequency points and generated an output power of 33.5 dBm with a PAE of better than 35% and 33.1 dBm with a PAE of better than 31% for low band and high band, respectively. When applied GMSK/EDGE, QPSK TD-SCDMA and 10MHz QPSK TD-LTE input signals, good ACPR performance are obtained with output power of 27.2, 26.5 and 25 dBm respectively.