Abstract: I welcome you to the fourth issue of the IEEE Communications Surveys and Tutorials in 2021. This issue includes 23 papers covering different aspects of communication networks. In particular, ...

Life expectancy at birth in the UK was 83.0 years for females and 79.1 years for males; this is an increase of 18 weeks from 82.7 years for females and 21 weeks from 78.7 years for males since 2019 to ...