Load-Modulated Balanced Amplifier Design for Handset Applications

In this letter, a load-modulated balanced amplifier (LMBA) design for handset applications is proposed. The proposed LMBA is demonstrated experimentally with GaAs-HBTs. A PAE of 40.7% and an NR ACLR of −37.7 dBc at an average output power of 31.7 dBm are measured at 3.75 GHz under 5G NR 100 MHz, DFT-s-OFDM, QPSK operation. Moreover, the proposed LMBA maintains more than 32.9% efficiency with an NR ACLR of below −37.7 dBc from 3.35 to 4.95 GHz, corresponding to 5G NR Band n77 and n79.