A concurrent dual-band/multi-carrier transmitter architecture for power and efficiency enhancement

This paper has demonstrated a novel a dual-band (DB)/multi-carrier (MC) transmitters (Tx) architecture to enhance output power and power-efficiency. Theoretical analysis revealed that crest factor (CF) of two modulated RF signals can be reduced by widening frequency-spacing of the signals. Then, the proposed Tx was comprised of concurrent DB/single-carrier (SC) power amplifiers (PAs) while a conventional Tx was comprised of single-band (SB)/MC PAs. The proposed Tx was able to achieve higher output power and power-efficiency than the conventional Tx because the PAs in the proposed Tx amplified the wider frequency-spacing signals with lower CF compared to that in the conventional Tx. The measurement results demonstrated that the proposed Tx achieved higher output power than the conventional Tx by 2.2 dB with 2-carrier WCDMA down-link signals at dual-band of 500 MHz and 800 MHz while using the same PA. The measured power-efficiency of the proposed Tx was 1.24 times as high as that of the conventional Tx.