If you are interested in how a 5G EN-DC Option 3 connection is set-up between the mobile device and different components in the network the best but also the hardest way is to look up the procedures in a number of different 3GPP specifications. 3GPP TS 37.340 is a good starting point for EN-DC. Another … Continue reading 5G EN-DC Option 3 – Call Flows
One thing I’ve been wondering for some time now is how in 5G EN-DC, user data is split between the 4G and 5G base station in a way that takes changing RF conditions into account. It’s no good to just assign a certain data rate to the 4G and 5G side when a split bearer … Continue reading 5G EN-DC: Flow Control Between 4G and 5G
This is a follow up post to my original post on 5G EN-DC, the LTE/5G Dual Connectivity (DC) variant of 3GPP 5G. About a year has passed and a lot of progress has been made in 3GPP TS 37.340, which describes the interworking between the LTE eNB and the 5G NR gNB. One thing that … Continue reading 5G EN-DC: Let’s Talk About Signaling – SRB1/2, SRB-3, Split-SRB
In many countries, 5G networks will be launched initially in a configuration referred to ‘Non-Standalone Architecture – Option 3’. This means that the mobile device connects to a 4G cell that has a co-located 5G cell which it can then include in the data transfer. This is why ‘option 3’ is also referred to as … Continue reading 5G EN-DC: How Does The UE Signal Its 5G Capabilities?
If you go by 3GPP and common sense it can be expected that most operators having an LTE network today will launch 5G as what is referred to as 5G EN-DC (eUTRAN New Radio – Dual Connectivity), a.k.a. 5G NR ‘option 3’ in 3GPP circles. In other words, mobile devices will still camp on the … Continue reading What Comes After 5G EN-DC?
In many cases 5G will come to smartphones, tablets and other devices in the form of 4G-5G dual-connectivity, also referred to as EN-DC (E-UTRAN New Radio – Dual Connectivity). While the mobile is in Idle state it will camp on a 4G LTE cell. A 5G NR cell is only added by the network once … Continue reading LTE Core Network Enhancements for 5G EN-DC
In the first part of this series, I emphasized that in 3GPP Release 15, a major focus is to get a first incarnation of 5G into the field that complements 4G LTE. Instead of today’s approach where a device is either connected to GSM, or to UMTS or to LTE, i.e. only to one technology … Continue reading 5G – Part 3 – Dual Connectivity (EN-DC)
In part 1 of this series, I’ve taken a look at the process of purchasing an eSIM online for roaming purposes and then downloading it to a smartphone. In this part, I’ll have a look at some technical details such as the home network operator of the eSIM, location of the Internet connectivity, performance and … Continue reading Downloading an eSIM – in Practice – Part 2
Recently I’ve been looking a bit at the 5G NR Radio Resource Control (RRC) protocol in 3GPP TS 38.311 to get an idea how it is structured and how it compares to the LTE RRC protocol specified in 3GPP TS 36.331. As Ralf points out in the comments below (thanks very much!) some parts of … Continue reading 5G RRC Protocol And How It Compares to 4G RRC
Network operators in a lot of countries around the world are getting ready at the moment to launch first 5G networks in the 3.x GHz spectrum (i.e. 3GPP band n78). One of the particularly interesting things about this band is that its made for TDD operation and not FDD as most operators are used to. … Continue reading 5G NR in 3.x GHz – Up- and Downlink Configuration