A 40-MHz Bandwidth Pulse-Modulated Polar Transmitter for Mobile Applications
Journal
2019 IEEE Topical Conference on RF/Microwave Power Amplifiers for Radio and Wireless Applications
Date Issued
2019
Author(s)
Abstract
This paper presents a new transmitter architecture for wideband mobile phone applications. By using a low-power high-speed low-resolution digital-to-analog converter (DAC), aliasing-free digital pulse-width modulation (AFDPWM), and pulse-modulated polar transmitter (PMPT) concurrently, high efficiency, wide bandwidth, and high linearity can all be achieved. For validation, a prototype transmitter was tested with a 40-MHz bandwidth orthogonal frequency-division multiplexing (OFDM) signal at a carrier frequency of 836.5 MHz. Using the proposed method, the prototype transmitter achieved an output power of 22.2 dBm and a drain efficiency of 35% with an adjacent channel leakage ratio (ACLR) of -31.5 dBc using a DAC resolution of just 4 bits at 4 GS/s. Moreover, AFDPWM provided sufficient linearity that no additional digital predistortion was required.
SDGs
Type
conference paper