Damian Anzaldo, Maxim Integrated
EDN (March 06, 2015)
This two-part article series reviews new developments in the Fourth Generation Long Term Evolution (4G-LTE) cellular standard. The articles explore LTE-Advanced (LTE-A) Release-12 (Rel-12) features and their impact on eNodeB radio frequency (RF) transmitters. The articles reveal how analog integration can overcome design challenges arising from the latest 4G developments. A Glossary of Technical Terms is appended to the end of each article to help with acronyms.
This article examines market forces driving global adoption of the LTE standard and trends in 4G radio access technology. Topics include carrier aggregation (CA), spatial multiplexing, and active antenna systems (AAS). Part 2 of this series explores the analog integration challenges in 4G base stations. Rel-12 features such as wideband downlink CA, downlink multiple-input multiple-out (MIMO) spatial multiplexing, and AAS with embedded RF, present new design challenges in next-generation eNodeB radios. A disruptive bits-to-RF solution can help engineers shape alternative radio transmitter architectures. The discussion focuses on novel RF digital-to-analog converter (RF-DAC) technology that yields a single-chip, wideband RF transmitter solution.