An all-digital synthesizable baseband for a delay-based LINC transmitter with reconfigurable resolution

作者：Yue Han^*; Shushan Qiao; Yong Hei

来源：Chinese Journal of Semiconductors, 2014, 35(11): 115001.

DOI：10.1088/1674-4926/35/11/115001

• Adaptive calibration
• All digital
• Limited resolution
• Linear amplification with non linear components
• Low Power
• Performance degradation
• Resolution improvement
• Synthesizable

The linear amplification with nonlinear component transmitter is a promising solution to high efficiency and high linearity amplification for non-constant envelope signals. An all-digital synthesizable baseband for a delay-based LINC transmitter is implemented. This paper proposes a standard-cell based synthesizable methodology which can be applied in the ASIC process efficiently without performance degradation compared to the manual layout. A scheme to overcome the limited resolution of conventional phase detectors is proposed. It employs alternative phase detector structures to provide reconfigurability for higher resolution after fabricating, resulting in an 11 ps resolution improvement. Due to the PVT variation, an adaptive calibration scheme focusing on the inherent imbalance between two delay lines is depicted, which reveals an effective EVM enhancement of 5.37 dB. This baseband chip is implemented in 0.13 μm CMOS technology, and the transmitter with the baseband has an EVM of -28.96 dB and an ACPR of -29.51 dB, meeting the design requirement.

• 出版日期2014