## 4 Artificial Intelligence (AI)-Enabled 6G Networks  
The disruptive emergence of highly distributed smart city mobile applications [33; 34; 35] such as the IoV, IoMTs, IoD, IoRT, IIoT, 3D virtual reality, and their stringent requirements in terms of the QoS and the need for the service providers to satisfy SLAs, have been a driving force for 6G. In addition, many of those applications are AI-Big data-driven, making it challenging if not impossible for 5G to satisfy those requirements. Therefore, 6G must provide battery-free device capabilities, very high data rates, a very high energy efficiency, massive low-latency control, very broad frequency bands, and ubiquitous \begin{table}
\begin{tabular}{l c c c c c c} \hline
**FeaturesNetwork** & **1G** & **2G** & **3G** & **4G** & **5G** & **6G** \\ \hline
**Start** & 1970 & 1980 & 1998 & 2000 & 2010 & 2020 \\
**Deployment** & 1984 & 1999 & 2001 & 2010 & 2019 & 2030 \({}^{\star}\) \\
**Technology** & AMPS, NMT, TACS & GSM, GPRS, EDGE & WCDMA, UMTS & LTE, WiMAX & MIMO, mm & mm & communications, VLC \\
**Frequency** & 30 kHz & 1.8 GHz & 1.6-2 GHz & 2-8 GHz & 3-30 GHz & 95 GHz-3 THz \\
**Multiplexing** & FDMA & TDMA/CDMA & CDMA & OFDMA & OFDM & OFDM \\
**Switching** & Circuit & Circuit, packet & Packet & All packet & All packet & All packet \\
**Core network** & PSTN & PSTN & Packet & Internet & Internet & Internet \\  & & & & & & \\  & & International roaming & & Mobile web & Machine & Tactile and haptic \\
**Primary services (in** & & voice calls, conference & Video & access, IP & vision, & internet, connected \\
**addition to previous** & Voice calls, SMS, MMS, WAP, WWW, and emails & conferencing & telephony, 3D & connected cars, autonomous \\  & & & GPS & videos, HD & smart homes, & systems, \\  & & & mobile TV & AR & holographic society \\
**Peak data rate** & NA & 50 Kkps (CPRS) & 21 Mbps (EDGE) & 21 Mbps & 100 Mb/s & 20 Gb/s & \(\geq\)1 Tb/s \\
**Mobility support** & NA & NA & NA & 350 km/h & 500 km/h & \(\geq\)1000 km/h \\
**Latency** & NA & 300 ms & 100 ms & 10 ms & 1 ms & 10–100 \(\upmu\)s \\
**Network energy** & & & & & & \\
**efficiency (compared** & NA & 0.01x & 0.1x & 1x & \(\geq\)10x & \(\geq\)100x \\
**to 4G)** & NA & NA & 0.6x & 1x & 3x & \(\geq\)15x \\
**Area traffic capacity** & NA & NA & 1 Kbps/m\({}^{2}\) & 0.1 Mbps/m\({}^{2}\) & 10 Mbps/m\({}^{2}\) & 1 Gbps/m\({}^{2}\) \\
**Connection density** & NA & NA & \(10^{4}\) & \(10^{5}\) & \(10^{6}\) & \(10^{7}\) \\ \hline  & \multicolumn{4}{c}{\({}^{\star}\)\(\rightarrow\) Expected; AMPS \(\rightarrow\) Advanced Mobile Phone System; NMT \(\rightarrow\) Nordic Mobile Telephone; TACS \(\rightarrow\) Total Access Communication System; GSM \(\rightarrow\) Global System for Mobile; GPRS \(\rightarrow\) General Packet Radio Service; EDGE \(\rightarrow\) Enhanced Data rates for GSM Evolution; WCDMA \(\rightarrow\) Wideband Code Division Multiple Access; UMTS \(\rightarrow\) Universal Mobile Telecommunications Service; LTE \(\rightarrow\) Long-Term Evolution; WiMAX \(\rightarrow\) Worldwide Interoperability for Microwave Access; MIMO \(\rightarrow\) Multiple Input Multiple Output; THz \(\rightarrow\) Terahertz; VLC \(\rightarrow\) Visible Light Communication; FDMA \(\rightarrow\) Frequency Division Multiple Access; TDMA \(\rightarrow\) Time Division Multiple Access; CDMA \(\rightarrow\) Code Division Multiple Access; OFDMA \(\rightarrow\) Orthogonal Frequency Division Multiplexing; PSTN \(\rightarrow\) Public Switched Telephone Network; SMS \(\rightarrow\) Short Message Service; MMS \(\rightarrow\) Multimedia Message Service; WAP \(\rightarrow\) Wireless Application Protocol; WWW \(\rightarrow\) World Wide Web; GPS \(\rightarrow\) Global Positioning System; HD \(\rightarrow\) High Definition; AR \(\rightarrow\) Augmented Reality; NA \(\rightarrow\) Not Applicable. \\ \end{tabular}
\end{table} 
Table 2: Characteristics of the wireless communication technology from 1G to 6G. broadband-global network coverage beyond what 5G LTE can offer.