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Release 10 (completed late 2010) marks the start of the LTE evolution and is often referred
to as LTE-Advanced. Then during late 2015, release 13 would bring even more features
encompassing new scenarios and improved specifications. This release is called LTE-Advanced
Pro and sometimes commercially dubbed 4.5G and seen as an intermediate technology between
4G, defined by the first releases of LTE and the upcoming new 5G air interface.
1.2 What is it meant by 5G?
Simply put 5G
2 – the fifth generation of mobile broadband technology – is a set of 3GPP
LTE releases created to define a new radio access network (RAN). This new work started
in late 2016 and it is been very recently released in late Q2 2018 under the name Release 15
or 5G NR (New Radio). Additional features, improvements and amendments are already
underway in Release 16 (5G phase 2). This work is expected to be done by the end of 2019.
The main focus for 5G has been to improve further the radio access network, aiming for
reliably supporting even more connected devices, with even higher bit rates and with even
lower latency.
So 5G is not a totally different technology but a continuation of the work started by 3GPP
with the release of LTE. As often illustrated by the 3GPP’s LTE logos (Fig. 1), 5G is the next
step after LTE Advanced Pro.
Commercial 5G networks are expected to be launched during 2019 and 2020.
2 SYSTEM ARCHITECTURE
The LTE system consists of an Access part and a Core part. The Access consists of an E-UTRAN
(Evolved Universal Terrestrial Radio Access Network) and the Core is formed by the EPC
(Evolved Packet Core). Altogether they form the so called EPS (Evolved Packet System).
Below on Fig. 2 a high-level representation of an EPS is depicted. Next a quick overview
of each block is given in order to aid understanding of the main functions.
2.1 E-UTRAN
Here is where all radio access to the network is handled. E-UTRAN or simply RAN (Radio
Access Network) is consisted of an eNodeB (E-UTRAN Node B, or just eNB) which for simplicity can here be seen as the “base station”. The UE or User Equipment, is the LTE mobile
device (for ex., a smartphone, a modem or a sensor) that connects to the eNB.
The eNodeB is a comprehensive logical implementation part of the RAN, responsible
for many important functions such as roaming decision of an UE between base stations,
scheduling, radio-resource handling, retransmission protocols, coding and various multiantenna schemes.
2. Not to be confused with 5GHz ISM frequency band.
Figure 1. 3GPP logos.
Release 10 (completed late 2010) marks the start of the LTE evolution and is often referred
to as LTE-Advanced. Then during late 2015, release 13 would bring even more features
encompassing new scenarios and improved specifications. This release is called LTE-Advanced
Pro and sometimes commercially dubbed 4.5G and seen as an intermediate technology between
4G, defined by the first releases of LTE and the upcoming new 5G air interface.
1.2 What is it meant by 5G?
Simply put 5G
2 – the fifth generation of mobile broadband technology – is a set of 3GPP
LTE releases created to define a new radio access network (RAN). This new work started
in late 2016 and it is been very recently released in late Q2 2018 under the name Release 15
or 5G NR (New Radio). Additional features, improvements and amendments are already
underway in Release 16 (5G phase 2). This work is expected to be done by the end of 2019.
The main focus for 5G has been to improve further the radio access network, aiming for
reliably supporting even more connected devices, with even higher bit rates and with even
lower latency.
So 5G is not a totally different technology but a continuation of the work started by 3GPP
with the release of LTE. As often illustrated by the 3GPP’s LTE logos (Fig. 1), 5G is the next
step after LTE Advanced Pro.
Commercial 5G networks are expected to be launched during 2019 and 2020.
2 SYSTEM ARCHITECTURE
The LTE system consists of an Access part and a Core part. The Access consists of an E-UTRAN
(Evolved Universal Terrestrial Radio Access Network) and the Core is formed by the EPC
(Evolved Packet Core). Altogether they form the so called EPS (Evolved Packet System).
Below on Fig. 2 a high-level representation of an EPS is depicted. Next a quick overview
of each block is given in order to aid understanding of the main functions.
2.1 E-UTRAN
Here is where all radio access to the network is handled. E-UTRAN or simply RAN (Radio
Access Network) is consisted of an eNodeB (E-UTRAN Node B, or just eNB) which for simplicity can here be seen as the “base station”. The UE or User Equipment, is the LTE mobile
device (for ex., a smartphone, a modem or a sensor) that connects to the eNB.
The eNodeB is a comprehensive logical implementation part of the RAN, responsible
for many important functions such as roaming decision of an UE between base stations,
scheduling, radio-resource handling, retransmission protocols, coding and various multiantenna schemes.
2. Not to be confused with 5GHz ISM frequency band.
Figure 1. 3GPP logos.