Scalable Resource Optimized LUT-Based All-Digital Transmitter

Abstract

In this paper, we present a low-resource look-up table (LUT) based solution for all-digital transmitters (ADTs) that addresses both the wide bandwidth and high carrier frequency flexibility. Traditional ADTs use real-time delta-sigma modulation (DSM) to convert a multiple-bit signal into a single-bit one, enabling the use of fast and inexpensive one-bit digital-to-analog converters (DACs) in the transmission chain. However, real-time DSM requires significant computational power to provide wide bandwidths and high carrier frequency agility. Our LUT-based solution achieves carrier frequency agility from 0.1 GHz to 7.62 GHz and delivers wide bandwidths of up to 150 MHz. We also introduce a new technique called “Half LUT Implementation” that allows us to halve the size of the LUT without sacrificing performance. The focus on simplifying and reducing resources in the transmitter is intended to reduce energy consumption and enable ADTs to be used in massive multiple-input/multiple-output (Massive-MIMO) applications.