Author: Martin

The spectrum situation for mobile services in the US has always been different from much of the rest of the world. More often than not, US network operators have to cobble together 5 and 10 MHz chunks of spectrum for their customers while in the rest of the world, aggregating 20 MHz channels is the norm rather than the exception. For 5G, the US again took a different path with mixed results so far. However, it now seems to be partly changed to match the rest of the world.

Continue reading The US Will Get 3.5 GHz Spectrum for 5G – But Not Much

Back in February I wrote a post on how to download and install apps from the Google Play store to an Android device without a Google account. At the time  I was using ‘Yalp’, which is ‘Play’ spelled backwards. Unfortunately, the app became a bit unreliable over the months so I was very happy when I found an incredibly good replacement recently after reading about ‘Google alternatives’ on Kuketz-Blog (in German).

Continue reading Aurora – Android Without the Play Store

Open source implementations of pretty much all GSM network and UE components have been available for quite some time now and there are people that do use the software for private and commercial purposes. For many years now, for example, the Chaos Communication Congress has a dedicated private GSM network and, in recent years, a UMTS setup was added. And now, and I am very happy about this, the first successful attempt to also set-up a private LTE network has taken place at this years cccamp#19.

Continue reading The State of Open Source LTE

‘Because We Can’ is the motto when it comes to technology and Chaos events so when cccamp19 came around there were no less than three backup microwave links available to the land based temporary fiber cable to the next POP that rodents find quite attractive. In the first post on the topic I’ve described the first two that bridged a distance over 10 km and offered a bandwidth of 10 Gbit/s. For this post I’ve collected some technical details about the microwave link they had all the way to Berlin which was 57 km away!

Continue reading State of Microwave Backhaul – Part 2

Unfortunately I could not come to cccamp#19 so I missed a lot of fun. Fortunately, people shared a lot of technical details online so I was able to pull together a number of interesting details about the different microwave backhaul links that were put in place for the event as a backup to the cross country fiber that was somewhat unreliable at the previous camp due to the rodent population.

The last time I had a closer look in 2012, a wireless backhaul link speed of around 500 Mbit/s was state of the art. Things have progressed nicely in the last 5 years, we are now at 10 Gbit/s, symmetrical, of course.

Continue reading State of Microwave Backhaul – Part 1

I like ‘Conversations’, my XMPP based messenger app on my smartphone and the list of people I interact with has grown steadily over the years. In some cases I would prefer, however, to use a messenger on my notebook with the same account as on my mobile. So far, I didn’t have a solution that I liked. There is of course Gajim, but unfortunately the current version doesn’t like the old libraries still used in Ubuntu 16.04. Updating to a newer OS version just for Gaijim was out of the question, however. But now I’ve found ‘Converse.js‘ a great web browser based solution that exactly fits my needs.

Continue reading Discovering Converse.js: A cool XMPP Web Client

When I was in the US recently, I noticed that AT&T now broadcasts 2 Mobile Country Codes / Mobile Network codes from their LTE base stations in the places in Illinois and Ohio I checked. One is their own, MCC/MNC 310/410, and the other is MCC/MNC 313/100. A quick search revealed that this is the code assigned to Firstnet, a network for emergency services and first responders such as police, fire departments, ambulances and other public functions that require high priority access in congestion situations. Wikipedia has an article about Firstnet here. Up to now I always thought that the US wanted to establish a separate network but it looks like I was either wrong or that they have changed their mind over the years.

Continue reading Firstnet – Some Technical Details

For various reasons that you can probably imagine, I usually don’t like to connect Android devices to Google accounts. Unfortunately, Google requires a login for the Play store. In most cases that is not a problem because I use the F-Droid store for most of my apps. However, some apps I (unfortunately) need on some devices are not available there because they are closed source. One way around this is to install ‘Yalp’ from the F-Droid store which can access the Play store without an account. Unfortunately this approach is a bit slow and unreliable so I had to look for an alternative.

Continue reading Installing Android Apps Without A Google Account

As indicated in the previous part on this topic I wanted to take a look at a second LTE network north of Chicago to see how networks are deployed and operated on this side of the Atlantic. I found this network to be a bit faster for me with data rates between 15 and 20 Mbit/s. Still comparatively slow but I’m hampered by the same issue as in the other network, i.e., my top of the line European smartphone does not indicate a single carrier aggregation combination for US bands. I really have to follow this up, as the spectrum landscape is so fractured in the US and networks are loaded quite a bit, so carrier aggregation is no longer only a ‘nice thing to have’.

Continue reading A Look At LTE Deployment North of Chicago – Part 2

A few weeks ago, two US network operators have launched 5G in the Chicago area, just when I happened to be there for a week. While I don’t have a 5G device that supports US deployments yet, I expected that, perhaps as a side effect, there would also be a significant LTE deployment. However, I was rather underwhelmed about the data rates I got. While I staid in Evanston, about 15 km North of Chicago, I could only get 5-15 Mbit/s from one network operator in most places I measured while I could at least get 10-25 Mbit/s from another network operator in that city. As that is very little compared to data rates I get when I travel to other parts of the world I started to investigate a bit.

Continue reading A Look At LTE Deployment North of Chicago – Part 1