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To get to it: Insert (main toolbar at the top) → New

• You have many ways to make a new object. Take a satellite for example. You could use the Orbit Wizard and define the orbit of the satellite using certain parameters, import the data of an active/retired real satellite, or load one from various file types.

To get to it: File (main toolbar at the top) → VDF Setup → Create VDF

The above is how you can make a standalone, shareable file. This is good if the person you're sending the file to is using the free viewer for STK. 

• If you're trying to share your scenario with your friend, and they can't see your data files, you've got two options. First, you use VDF setup to create a compressed .vdf file. Your other option is to convert the entire individual scenario folder that STK generated when you saved your scenario, into a zip file. 

To get to it: Insert → New → Facility.

Within the properties of the facility, you can input its exact latitude, longitude, and altitude coordinates.

• If your facility is floating in the air on the 3D globe, you probably accidentally wrote your altitude in kilometers instead of just straight meters. Otherwise, maybe your terrain data didn't load properly?

A simplified point on the map or in space that you want your satellite or ground station to track. 

NOTE: It does not have actual physical hardware like transmitters, like the ground station would. 

To get to it: Insert → New → Target.

You can drop this target onto a specific city or coordinate point. It acts like a benchmark placeholder to calculate line-of-sight tracking windows or imaging paths.

An object that defines the physical FOV (field-of-view) cone, camera footprint, or antenna beam width.

NOTE: It must be nested underneath a parent object, like a satellite or facility.

To get one: Insert → New → Sensor → (Parent Object)

• If you want your sensor to track the ground, you'll need to change its pointing properties. By default, satellite sensors in STK point straight down, meaning you'll need to change the pointing properties to "Target Tracking" to get the sensor to look at a specific ground station. 

A hardware component attached to an asset that generates and sends out radio signals at a specific frequency and power level.

NOTE: It must be nested underneath a parent object, like a satellite or facility.

To get one:  Insert → New → Transmitter → (Parent Object)

In the properties of the transmitter, you can define the exact carrier frequency and output power (in watts).

A hardware component that listens for and captures the radio signals sent by a Transmitter

NOTE: It must be nested underneath a parent object..

To get one: Insert → New → Receiver→ (Parent Object)

The parent object, in this case, is what ever is receiving the Transmitter's signals. Your frequency and bandwidth settings here must match your Transmitter EXACTLY, else it WILL NOT WORK. 

• If your link budget shows zero signal, even with clear line-of-sight, ensure that the receiver and transmitter frequencies match each other in numeric value and in units...

To find this: Right click your Transmitter/Receiver → Properties → Model

You can select standard analytical shapes, or upload custom .fna antenna map files.

To make one: Right-click the LOS access line between your Transmitter & Receiver → Report & Graph Manager → Link Budget

• Usually, the most important metrics to look at are E_b/N_0 and BER. If those fall below your hardware's minimum threshold, your satellite simply won't drop data. 

This value updates in real-time inside your link budget reports as your satellite orbits overhead and changes distance from the ground station.

This is used by the link budget to evaluate raw link performance before you lock in your final hardware data rate settings.

Unlike C/N, this value is completely independent of the receiver's actual bandwidth filters. 

THE "pass/fail" number for your link. 

• If you are below this value for your hardware requirements, your data packets will be completely corrupted. If you're above it, you have a link margin (essentially a safety buffer).

It is calculated in your link budget, and is based directly on your E_b/N_0 and modulation type.

Calculated automatically by STK based on pure distance and frequency. Typically the largest source of signal loss in your link budget.

Within the RF properties of your Scenario object, toggle atmospheric models (e.g. Crane, ITU-R rain).

• If your signal dropped without anything moving, this is what might've happened. STK will simulate statistical weather over your facility if you have a rain model enabled. High-frequency bands will take more of a hit than lower-frequency bands. 

Calculated automatically by STK when an atmospheric absorption model is checked in the Scenario properties. 

It becomes very punishing when a satellite is low on the horizon because the signal has to cut through way more air.

Causes your signal to fade erratically, or "twinkle".

"Enable it under the advanced environmental loss settings for fine-tuning high frequency ground-to-space links"

Tracked inside the link data reports. 

NOTE: Your receiver's tracking loop must be wide enough to accommodate this shifting frequency, or the signal will drift completely out of band during an overhead pass.

Within the properties of your Transmitter/Receiver antenna.

A higher gain value leads to a tighter, more powerful beam, but also requires more precise physical pointing. 

Used by STK as a baseline reference point to calculate the relative gain of all real antennas.

A definitive measure of "loudness" of your transmitter assembly found in your link budget reports.

A higher G/T value signifies that your ground station is incredibly sensitive and good at pulling weak, faint signals out of background space static. 

Within Receiver properties → Noise.

• Lower temperature is better because the colder the system noise temperature (in Kelvin), the less background static your hardware creates, making it much easier to hear your satellite.

Within BOTH Transmitter & Receiver Properties → Basic → Definition → Model Specs → Tick the checkbox "use" under Polarization 

• Typically, we use either RHCP or LHCP (Right/Left-Hand Circular Polarized) since circular signals don't care if the satellite is tumbling or spinning in place.

Computed automatically by STK based on the settings of the antenna. 

• If you mismatch completely (i.e. transmitter on RHCP, receiver on LHCP), you're going to drop a large amount of signal power that'll kill your download...don't do that!

Allocation Bandwidth: the physical width of the frequency spectrum channel your radio occupies

Data Bandwidth (aka Data Rate): the actual speed at which bits travel through that channel

Within Transmitter/Receiver properties (finish)

NOTE: Your receiver bandwidth must be wide enough to encompass your transmitter's signal plus any extra frequency room needed to account for Doppler shifts.

Within Receiver properties → Definition → Find the three dots next to the default receiver model, and switch it to the complex model

• Use this when you need to match your simulation to a real-world radio data sheet.

To get one: Insert → New → Radar

Radars can be attached to a ground facility to track incoming space debris, or dropped onto a spacecraft for Earth-imaging radar (SAR).

Right-click the access link → Properties → Attributes

You can make the link line turn one color when the link margin is healthy, and flash another color when the data corrupts.

To make one: Insert → New → Chain → Add your assets in order 

This allows you to test out long, multi-stop relay paths to see if data can successfully bounce from one asset to another to reach its final destination. STK will find the exact windows when data can hop through the entire network successfully.

To make one: Insert → New → Constellation → Put all of your identical objects inside of it.

It would be in your best interest to run a report against your target to check your overall global coverage. 

Configure by pointing a transmitter on Satellite A directly at a receiver on Satellite B. 

This is very important for tracking cross-country data relays in low-Earth orbit constellations.

Uplink: the command signal sent up from a ground facility to the satellite.

Downlink: the science data, pictures, or telemetry streamed down from the satellite to your ground tracking dish.

You need to make a pair consisting of a transmitter and a receiver for uplink, and another identical pair that'll just be for downlink. 

• Please use DIFFERENT frequencies across your pairs. If both pairs transmit and listen on the same frequency, your transmitters would effectively blind your receivers. Uplink needs its own frequency, and downlink needs its own, unique frequency.