A four-band TD-LTE transmitter with wide dynamic range and LPF bandwidth calibration

摘要

In this work, a four-band (Band 34 and Band 38-40) TD-LTE (Time Division-Long Term Evolution) transmitter (TX) is presented and fabricated in a 0.13μm CMOS technology. The TX adopted a direct up-conversion structure and integrated a fine digital variable gain amplifier (VGA), segmented R-2R ladder DACs, high linearity up-conversion mixers and wide dynamic range programmable gain amplifies (PGA). An optimized automatic bandwidth calibration circuits compensate a targeted 30% process variation. A 1.78% error vector magnitude (EVM) is achieved, with the adjacent channel power leakage (ACPL) ratio below -50dBc at 10MHz bandwidth, 16QAM modulation. The dynamic range of this TX exceeds 90dB with a fine step of 0.5dB, and the third harmonic distortion (HD3) achieves -54dBc. The TX dissipates 150mW at maximum output power.