Over the years, I’ve used LineageOS and its predecessor CyanogenMod on my personal devices such as the Samsung Galaxy S4 and, for the past few years, on the Samsung S5. But my S5 is aging so I was looking for a replacement. There is a LineageOS port for the Galaxy S6 but it seems to be quite experimental, I kept having power drain issues due to some system task starting to run wild after a few days. There’s also a version for the Galaxy S7 which is already kind of hard to get on the market but a version for the S8 is missing. The more surprised I was to see that there is a version for the relatively recent Galaxy S9.
The weekend is almost over and before I board the train back to Cologne, I thought I’ll do a quick post on my talk about the history of mobile networks and mobile data communication in the past 30 years at the Vintage Computer Festival Berlin this year.
While I’m typing this I’m sitting in the train from Cologne to Berlin, on my way to this year’s Vintage Computer Festival Berlin (VCFB). It’s beautiful sunny weather, unlike last year, when an autumn storm turned my train trip into a nightmare.
Like last year, I have brought a little exhibit with me again, this time about GEOS, a graphical user interface for the masses that was very popular in the second half of the 1980s. In addition, I’ve spent the last few weeks collecting my thoughts and pictures about the evolution of wireless networks and mobile data communication in the past decades. I will present the result in a 90 minute talk tomorrow, Saturday, 12 October. The talk will be recorded and perhaps also live streamed in case you are interested. I intend to hold the talk in German but there will surely opportunities in the future to record an English version as well.
Sometimes it is just a lot more convenient to do a map search on the PC rather than on the phone. Nevertheless I still want to have the result in Osmand (OpenStreetMap for Android) on my smartphone for later use, e.g. for car navigation. So my approach so far was to first search the location on the PC and once I knew where it is I would manually locate and bookmark it on the smartphone again. Far from ideal… However, I just found out a much simpler way to do this by accident:
After upgrading to VDSL vectoring with a 100 Mbit/s downlink and 40 Mbit/s uplink in Cologne recently, I soon figured out what to do with the additional uplink speed: Advanced synchronization with my network behind a fiber line in Paris. Equally soon I noticed that no longer is my access link the bottleneck but rather under-dimensioned backbone links. So I had to find a way to creatively route my traffic around the problem.
In 5G, Massive MIMO is considered as the holy grail to increase individual datarates, to improve cell capacity, to extend range, or any combination of these. mMIMO is not a single technique, however, there are a number of different flavors that can to a degree be mixed and matched to achieve different things.
I recently came across this paper of Huawei on 5G Spectrum matters and one paragraph in particular caught my attention:
“[…] inter-operator synchronisation and alignment of uplink/downlink transmissions (slot and frame synchronization) is […] necessary for efficient deployment of 5G NR networks in unpaired assignments.”
In other words this sentence says that network operators using adjacent spectrum have to synchronize their radio networks to avoid interference. So why is this necessary and what exactly does that mean?
Remember the days when you traveled in Europe and had to pay high prices for voice and data roaming as soon as you crossed a border or had to buy a local SIM card for reasonably priced mobile Internet access? It seems like those days are long gone but that’s actually not the case, free roaming in the EU only came into effect last year. And even worse, there are still places on mainland Europe apart from Switzerland that are not part of the EU, where one gets a bitter reminder of how things were in the past. An interesting example is Monaco.
Interested in the past, present and the future of microprocessors? If so, the video of Sophie Wilson talking about the ‘Future of Microprocessors’ at Juliacon is a must see! In case the name Sophie Wilson doesn’t ring any bells, have a look at what Wikipedia says about her.
Her presentation will not only tell you about the history of microprocessors but also why performance hasn’t really increased in the past years, the reasons behind this and why the price per transistor on a chip has started increasing again with further miniaturization instead of a further decreasing, which has fueled Moore’s law for the past decades. And most important she will give here educated opinion on where we will go from here.
The abbreviation EN-DC (eUTRAN New Radio – Dual Connectivity) indicates that in this type of 5G deployment, 4G LTE and 5G NR will be used simultaneously. However, it looks like that the combination of some frequency bands might prove to be a bit problematic due to self interference as laid out in this interesting whitepaper recently published by Keysight (see page 4).