Mdthbs

My story takes place on a hot desert planet that is a colony. At some point people are out in a very hot and inhospitable area of the desert. Dust storms, high heat, constant wind, etc.

Characters have tech that allows them to access the planetary network via satellite. But I'd like them to be out there and get isolated without access - to be truly disconnected.

I assume that a heavy storm with blowing sand and lots of dust in the air would affect things, but what about on a normal day with no severe storm?

I had thought about having this part of the planet have some natural way to interfere. Possibly a magnetic field or something.

I'm not sure if that would work, looking for ideas.

Satellite signals are purposefully jammed in this area by the owners of the satellites.

The desert is territory which is politically hostile to the owners of the satellite system. To prevent persons living in the desert from taking advantage of the satellites (and possibly using their tech against the owners), signals are purposefully jammed by a geostationary satellite over the desert. It is possible to jam GPS signals, and so presumably every thing else can be jammed as well.

https://www.economist.com/international/2013/07/27/out-of-sight

Or maybe the desert is remote enough that satellites can cease signalling while traversing them then turn back on to serve their home countries.

The one signal your characters can receive is a Voice of America propaganda signal. The rest is squeaky white noice.

weird location + past war.

say your desert is at some high or low latitude where there just generally aren't a lot of people. the satellite communication network flies at mid to low inclinations where all the people live, but your remote desert colony is out of the way and no/few satellites fly overhead. They COULD pay for a comm sat with a higher inclination orbit, but if they are a poor colony that may not be in the cards for many years.

GEO sats kind of ruin that answer... maybe there's a lot of debris in orbit from a war in the past that make GEO orbits a mess, and all current comm sats are in LEO. Count MEO in this category too for you Molniya fans, all that junk will smash those too. The debris and space junk in the lower orbit all fell back (takes 20 years or less for lower orbits due to atmospheric drag) but the higher altitude orbits are basically unusable. In that scenario the answer above works to isolate your desert colony.

Solar Storm

A solar storm can take out satellites as well as disrupt satellite communication.

It could run from a few hours to a few weeks or even destroy the satellite. The 1859 Carrington Event caused the telegraph system to shock operators and even continue running after the power was disconnected. The same event today would take out the power grid and block communication.

This is going to be the most mundane solution to the problem that you're going to get, but it could be as simple as static electricity.

Deserts are hot dry environments across which winds can whip up quite easily. These conditions actually make them ideal static electricity generators and it's said that dust storms are strengthened in the desert because of it.

Of course, static electricity can also damage your electronic devices so put the two together and you have a perfectly plausible reason for why your crew were cut off in the middle of the desert; their devices failed because of a static electricity event.

I've never used a smartphone or other device in a desert, but I'd imagine that's not the only issue you might face. Sand in the charging port would be problematic as well, and if you have it out at the right time I really don't know how even minor sand blasting impacts a AMOLED screen but I'm guessing it can't be good for the device.

Important safety tip when you get right down to it; if you're navigating by GPS in the desert, always remember to properly earth your camel.

The dust and sand of your dry world could create powerful discharges of static electricity that would generate bursts of RF that effectively jam the satellites uplink or downlink or both

The interference would be similar to a spark gap transmitter.

Poor software design, and choices that you later regret.

We have real examples. Remember the Y2K bug? Did you know GPS has a mini-version of that bug, that affected lots of devices in April 6, 2019?

That's because GPS satellites uses ten bits to represent datetimes in their broadcasts. They can only represent timespans of about 1,024 weeks. So starting from whatever date and time they consider zero, they can count up to nineteen years and a few months. For comparison, modern software like nowadays browsers uses 64 bits to represent date and time. Most of Microsoft's software can handle dates from 00:00:00 in January 1, gregorian year 1 to 23:59:59.9999999 UTC, December 31, gregorian year 9999.

GPS was designed to use only ten bits for dates and times because it is cretaciously old, for computer standards - it was released in 1973. And the system has been working well enough, and devices get obsolete fast enough that people would rather reset the "datetime zero" every nineteen years rather than fix this "flaw". They've had plenty of opportunity - the oldest GPS satellite in operation was launched in 1997. It would be pretty easy to add more bits to the datetime - each bit doubles the span of dates that can be represented. But no one wants to fix what is not broken.

Prior to April 6, 2019, the "date zero" for GPS was August 21, 1999. On April 6, 2019, all devices that could not update their software started thinking they were receiving satellite broadcasts from that "date zero". And broadcasts from April 7, 2019 were processed as being from August 22, 1999. April 8, 2019 was understood as August 23, 1999 and so on. At best the affected devices would show wrong dates in their user interface, but mostly they ignored the GPS broadcasts after comparing the broadcast date with their own internal clock. Ignoring all GPS broadcasts means you cannot get a reading so you won't know where you are.

And you know what kind of devices could not be updated? Think TomTom and Garmin handheld GPS devices that have no Wifi connectivity and no USB port, and which some people love to use when doing tourism because they won't learn how to use an Android or iPhone.

Devices like this:

And even when they do have the port or connectivity to update, the company will force users to buy new hardware or be left without updates. This happened in 2018.

Now imagine your characters in the desert planet. The planet has a satellite network that worked fine for some period - maybe millenia, maybe even longer eras. It just happens that the satellites have hit the maximum date they will hold in their memory. At the next tick, they will reset to their date zero and start counting from there.

Worse, their date zero is out of the range your characters' devices can use. And they don't have access to the satellites control system, or maybe updating their dates will cause something else to fail. And the only place where you can buy new hardware is a few star systems away. Your characters may develop some hatred towards IT professionals from the past.

Don't want to get too technical with programming and binary code? Just say some bug happened that is causing issues.

Or use something else to make the satellites dysfunctional. Maybe they require a password that you don't have. Maybe a prank went wrong and the satellites have been trying to calculate the last digit of Pi for millenia. Maybe the poles of the planet shifted and the compasses on the satellites aren't handling it well, so they are pointing their dish antennae to the wrong hemisphere.

You've got the tech, but have you got the cash?

Some satellite based system such as satellite phones charge you by use. Your colonists may have ran out of data.

The catch-22 is that extra gigabytes or satellite time can only be bought online, so they won't be able to browse for a while.

They'll be good to go when their internet plan renews - as long as the satellite company is able to charge theor credit card successfully.