## 3 Mobile Communications Background
### The 3 GPP Releases for Mobile Communication Systems  
The Third Generation Partnership Project (3 GPP) was founded in December 1998 as a cooperative organization for telecommunication standards. The 3 GPP was founded by the  
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European Telecommunication Standards Institute (ETSI) and other standard development organizations (SDOs) from around the globe to develop new cellular network technology. The seven organizations involved and their countries are as follows:  
* ETSI--European Telecommunications Standards Institute (Europe),
* ATIS--Alliance for Telecommunications Industry Solutions (USA),
* TTC--Telecommunications Technology Committee (Japan),
* ARIB--Association of Radio Industries and Businesses (Japan),
* TTA--Telecommunications Technology Association (South Korea),
* TSDSI--The Telecommunications Standards Development Society of India (India),
* CCSA--The China Communications Standards Association (China).  
Cellular technology is continually evolving with 3 GPP, new features, and services that significantly improve mobile communication systems. The development of a global 3G mobile phone operating on 3G system specifications was the main goal of 3 GPP. GSM, GPRS, EDGE, UMTS, HSPA, LTE, LTE-Advanced, and LTE-Advanced Pro 5G standards development and maintenance were later added to the scope [50]. Various 3 GPP releases for earlier communication technologies up to the 5G standards, development, and maintenance are presented in Table 4.  
\begin{table}
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**3 GPP Release** & **Frozen Date** & **Main Feature** & **Data Rate** & \begin{tabular}{c} **Spectral** \\ **Efficiency** \\ \end{tabular} \\ \hline Release 99 & 1999 & 3G UMTS incorporating WCDMA & 2 Mbps & Low \\ \hline Release 4 & 2001 & UMTS all-IP Core Network & & Low \\ \hline Release 5 & 2002 & HSDPA, IMS & DL: 14 UL: 0.4 & Low \\ \hline Release 6 & 2004 & HSUPA, MBMS, Push-to-Talk over Cellular (PoC), & DL: 14 UL: 5.7 & Low \\ \hline Release 7 & 2007 & Enhancements in QoS and latency, VoIP, HSPA+, NFC integration, EDGE evolution & DL: 28 UL: 11 & Low \\ \hline Release 8 & 2008 & LTE, SAE, OFDMA, MIMO, Dual-Cell HSDPA technologies were introduced & Up to 300 and 75 & High \\ \hline Release 9 & 2009 & \begin{tabular}{c} LTE/ SAE improvements, Introduction of a Public \\ Warning System (PWS), IMS emergency sessions, \\ WiMAX/LTE technologies \\ \end{tabular} & DL: 100, UL: 50 & High \\ \hline Release 10 & 2011 & Introductions of LTE-Advanced, Backward compatibility with Release 8 (LTE), Multi-Cell HSDPA technologies & DL/500 Mbps & High \\ \hline Release 11 & 2012 & Enhancement to LTE-advance, Heterogeneous networks (HetNets) support & DL/500 Mbps & High \\ \hline Release 12 & 2015 & \begin{tabular}{c} More enhancement to LTE-Advanced, Carrier \\ aggregation (2 uplink carriers, 3 downlink carriers, \\ FDD/TDD carrier aggregation) \\ \end{tabular} & \begin{tabular}{c} 1 Gbps \\ DL/500 Mbps \\ UL \\ throughput \\ \end{tabular} & High \\ \hline Release 13 & 2016 & \
\begin{tabular}{c} Introduction of LTE-U/LTE-LAA, LTE-M, Elevation \\ beamforming/Full-dimension MIMO, and Indoor \\ positioning \\ \end{tabular} & DL/500 Mbps & High \\ \hline Release 14 & 2017 &
\begin{tabular}{c} The start of 5G standardization, Mission Critical Video, \\ and Data over LTE. \\ \end{tabular} & 10–20 Gbps & High \\ \hline \end{tabular}
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Table 4: 3 GPP Releases and important features.