Uncategorized – Page 26

Reality Bites – Flight Simulation – Part 1

I’ve had a fascination for flying pretty much for as long as I can remember and some years ago, I bought my first book that taught me the theoretical knowledge required for a private pilot license. But for a number reasons, flying a small airplane in reality hasn’t been in the cards so far. Also, I was not very interested in exploring the possibilities of a flight simulator, so the dream remained a reading exercise. However, several things have changed my mind about flight simulators recently.

The Rise Of The Bluetooth Mouse

Some trends in the tech industry can be rather slow. Take wireless mice, for example. I’m pretty sure that for more than a decade, wireless mice with a Bluetooth air interface have been on the market. I bought one 3 years ago but couldn’t use it because Ubuntu 16.04 would not support it. I tried again using it after upgrading the OS, but I didn’t like the hard to press buttons and the loud clicking sound of the model I bought. The Bluetooth link itself was working nicely, though. Recently, however, I had to come back to the topic when a USB port on my Lenovo X13 stopped working and I couldn’t connect a USB mouse dongle anymore.

Ubuntu Linux on the Bleeding Edge: Performance on a Notebook with an Intel 12800H and an Nvidia GPU – Part 2

In the previous blog post, I’ve been taking a look if and how well Ubuntu Linux runs on a high performance notebook with a state of the art Intel 12800H processor and an Nvidia RTX A2000 8GB GPU. While it took me a bit to set up the system so it wouldn’t sporadically freeze and use the GPU, the performance compared to ‘standard’ notebooks is quite stunning.

Running Ubuntu Linux on Bleeding Edge Hardware: Dell Notebook with an Intel 12800H and an Nvidia GPU

Normally, I’d say that raw computing power should be in the cloud, or perhaps under my desk, but definitely not in my backpack. That’s because computing power comes at a price: The notebook gets heavier, battery life becomes shorter and the power supply that has to supply at least 120 Watts of power is a heavy brick on its own. Unfortunately, I do have an application I use almost every day that is very much single threaded and behaves sluggishly even when using up to date standard notebook hardware. So I relented and got a state of the art notebook with one of the fastest CPUs currently on the market, and, as it came as part of the package, a dedicated Nvidia GPU. That definitely fixed the sluggishness of the application. The next question that obviously came to my mind then was how well and how fast this notebook with its latest and greatest hardware would run with Linux!?

Improved Network Selection Speed When Roaming

One thing that always bugged me when crossing a country border is that my mobile devices took endlessly to select a new network. That was probably because the device first searched all frequency bands for all available network and only then presented the results. One way out was to temporarily switch to GSM only mode, select a network and then switch LTE/5G back on. But it seems that finally the problem was recognized and addressed! While automatic network selection still takes ages, my current mobile presents the networks in manual network selection mode as soon as they are found. This way, selecting a roaming network just takes a few seconds. Very nice, thanks you!

When All Else Fails – The Garmin InReach Mini 2 – Part 9 – More Iridium Tech Stuff

In part 8 on this series on the Garmin InReach Mini 2 and the Iridium network behind it, I’ve assembled a summary of the few pieces of technical background information that is available on the Internet. Iridium offers a number of different services such as voice telephony and SMS, and quite a bit of the higher layer protocols seem to be adapted from GSM. Looking at the messaging service provided by Garmin’s InReach Service, I came to the conclusion that it is most likely NOT based on Iridium SMS. Instead, it looks like the service might be based on the Short Burst Data (SBD) service. I can’t be sure because there is no documentation, but here’s how SBD works:

When All Else Fails – The Garmin InReach Mini 2 – Part 8 – Iridium Tech Stuff

Ok, it’s nice to know that in case all terrestrial networks fail in my area, I will probably still be able to send and receive messages between Garmin InReach devices that use the Iridium satellite network. There are only four Iridium ground stations in the network, so it’s likely that a local or even country wide power outage would leave that infrastructure untouched. Being an engineer, I of course would like to know more how the Iridium and the Garmin InReach service actually work, what kind of protocols are used, etc. etc. Unfortunately, there is very little official information out there that goes into the technical details. Everything about the system is proprietary. I can’t even be certain if the messages that are exchanged between InReach devices remain in the network, or if they first go to some Garmin server and then back into the network. Should they be routed via some extra Garmin infrastructure, how is this part connected to Iridium and how redundant is it? Questions over questions. Fortunately, I’m not the only one who’s interested in the details and when digging a bit, one can find very interesting technical details on the Internet.

When All Else Fails – Part 7 – Satellite Distribution

In the previous parts on this topic I have mentioned a few times how amazed I am that despite a transmit power of only 1.5 watts, the small Garmin InReach Mini 2 can send text messages to Iridium satellites that are thousands of kilometers away. This becomes even more impressive when one sees where the satellites are actually located during the message transfer.

The screenshot on the left was taken from the Irdiumwhere website at a time when my Mini 2 reported that a message had been sent successfully. According to this map, which is updated in real time, the message I sent from Cologne was either exchanged with a satellite that was just over the Mediterranean island of Sardinia or with a satellite that was over Iceland at the time.

I continue to be amazed, so in the next part of this series, I’ll have a look of what kind of technical information is available on the Iridium constellation.

When All Else Fails – The Garmin InReach Mini 2 – Part 6: Power Consumption

The Garmin InReach Mini 2 charging at 2.5 watts

When all else fails, my Garmin InReach Mini 2 would be the last device standing. The question then is how long I could use it before its battery runs out. On their web page, Garmin says the device has a standby time of up to 30 days (720 hours). But that’s the best case with full view of the sky and the complete horizon. In my urban valley scenario, that’s unlikely to happen. So what kind of endurance can I expect in such an environment?

When All Else Fails – The Garmin InReach Mini 2 – Part 5: Composing Messages

Composing a text message on the Garmin InReach Mini 2

This might seem like a benign topic, but how does one compose text messages on the Garmin InReach Mini 2? As you can see above, the device has no keyboard, not even digit keys at the front. This is quite intentional, as I wanted to have a device that is as small and as light as possible for emergency communication with members of the household, should local terrestrial networks fail. What the device has, however, are five keys at the side. One of them is the firmly protected EMERGENCY button to contact an emergency center. On the right, there’s an OK and a BACK button. And finally, there’s an UP and DOWN button on the left. Not much to work with.