How Do You Get Data From Satellites To Earth?

Connect To Ground Stations

A ground station is a physical location with an antenna that allows a satellite operator to downlink the imagery from their satellite after it's been collected.

When launching, most companies don't build their own ground stations. Instead, they look for partners who already have large networks of ground stations.

These can be located anywhere in the world, but there are some advantages to having them in certain locations.

For example, if your satellites are in sun-synchronous orbit, then having the ground station close to the north or south poles allows you to have more passes per day for your satellites and, therefore, more down-linking capabilities.

Mission Planning Is Often Overlooked

Mission planning is an often overlooked aspect by many satellite operators.

As you can imagine, as orders come into a satellite company to be scheduled and collected, it’s sometimes a challenge to understand how you will orchestrate those orders based on the satellites in your constellation.

There are a number of variables that are at play:

1. The number of satellites in your constellation
2. The ground station network that you've chosen,
3. What the weather will be like when a satellite is potentially collecting an order. So if it’s going to be cloudy, you want to avoid that collection.
4. And then there may be other nuances like priority customers who you may want to serve first.

The Software That Makes This Happen

So mission planning software takes that order pool, that available order pool, and optimizes it for collection within your satellite constellation.

Command and control software allows a satellite company to send information to the satellite to perform different manoeuvres, capture certain imagery, or deal with other situations in space.

That software is complicated and needs to work with multiple different ground stations.

Depending on your configuration, you'll need to understand

• the different ground stations that you're connected to,
• the gateways between them,
• and also all of the components in your satellite that need to be controlled

Fixing Downloaded Data

When data is collected on a satellite and downlinked, it comes in a very raw format. It's not Georeferenced. It’s not Orthorectified.

There are a number of different controls that need to be put on data to make sure it's accurate for customers who are receiving it.

This is known as raw data processing or level zero to level one processing.

It's something that's very challenging and requires a detailed understanding of each satellite in the constellation and specific adjustments required to correct the data on those satellites.

When you're launching a satellite constellation, there are many things to worry about.

Not only do you need to figure out your payload, your optics, some of the other sensors on the satellite, and how you're going to get launched.

But you also need to figure out how you're going to monetize your data, how you're going to operate your satellite, and how you're going to get that data down on a day-to-day basis.