A Sub-GHz multimode digital polar transmitter for 802.11ah and NB-IoT applications. (February 2023)

• Record Type: Journal Article
• Authors: Li, Tong; Yin, Yun; Liu, Yangzi; Xu, Hongtao; Min, Hao
• Is Part Of: Microelectronics journal. Volume 132(2023)
• Publication Date: 2023-02
• Subjects: CMOS -- 802.11ah -- NB-IoT -- Polar digital transmitter (DTX) -- Efficiency-enhanced -- Switched-capacitor digital power amplifier (SC-DPA); Microelectronics -- Periodicals; Microélectronique -- Périodiques; Microelectronics; Electronic journals; Journals - contents and abstracts; Periodicals; 621.3805
• DOI: 10.1016/j.mejo.2022.105673
• Languages: English
• ISSNs: 0959-8324

Abstract

Abstract: This paper presents a sub-GHz multimode efficiency-enhanced digital polar transmitter for IoT applications. The Class-G technique and wideband matching network are introduced in the switched-capacitor digital power amplifier (DPA) to enhance the 6 dB back-off efficiency and achieve 550–950 MHz wide frequency coverage. The digital baseband processing module is flexibly reconfigurable to support both 802.11ah and NB-IoT protocols. Moreover, the canonic signed digit (CSD) coding and first-order hold (FOH) interpolation techniques are employed to reduce power consumption. Implemented in 55 nm CMOS technology, this digital transmitter (DTX) achieves 23.7dBm peak power, 44.6% peak PAE and 36.1% PAE at 6 dB power back-off at 800 MHz. The DTX obtains 16.7dBm average output power, 33.9% average PAE with −28.8 dB EVM for the 2 MHz 64QAM 802.11ah signal, and 18.6dBm average output power, 37.5% average PAE with −19.8 dB EVM for the 12-subcarrier 180 kHz NB-IoT signal.