How do I analyze communication links in STK?

I wanted to add an additional comment. As a systems engineer, I like to use the Carrier to Noise Ratio and the Bit Error Rate. 

Carrier to Noise is exactly what it sounds like Carrier divided by Noise. If you have more of the Carrier Signal and less noise, you have a better signal because you can ‘hear’ the carrier signal over the noise. If the signal is too noisy then you cannot ‘hear’ the signal.

For Bit Error Rate, the worst signal is 0.5 which means every other Bit sent, would be an Error, so sending 000000 could give you a signal of 0101010 or 100110 or 100101 meaning the signal is complete jumbled. If you have 1*10^-30 you have 10^30 bits sent before you get a single error, so that is a crystal clear signal.

Here is the notes from the help.

The carrier to noise ratio (C/N) where C is the carrier power and N = kTB (Boltzmann's constant x system temperature x bandwidth) is the noise power.

Bit Error Rate (BER) is the probability that a bit is in error (i.e. a zero is transmitted but a one is received). The BER is the number of bits in error divided by the total number of bits sent. STK uses table lookup from a .mod file to extract a BER given an Eb/No. STK interpolates the table as necessary to determine the appropriate bit error rate for a particular bit energy level. If the bit energy is smaller than the first value in the table, the bit error rate for the first value is used. If the bit energy is larger than the last value in the table, a default bit error rate of 1.0e-30 is used to indicate no errors.

Thanks Drew. This is what I was looking for. 

Hello,

Yes, the communications module is available in STK Pro! To analyze communication links in STK, follow these steps: 

1. Create a New Scenario: 

• Open STK and create a new scenario. 

2. Add a Ground-Based Receiver: 

• Insert a Receiver object and place it at your desired ground location. Define the Receiver’s model specifications and additional details on the Receiver’s properties page. 

3. Add a Satellite Transmitter: 

• Insert a Transmitter object and place it on your satellite. Specify the Transmitter’s properties as you did with the receiver. 

4. Impose Communication Constraints: 

• Adjust the receiver and transmitter constraints to satisfy your RF criteria (e.g., minimum elevation angle, frequency, etc.) This is found in the Constraints section of the properties page. 

5. Compute the Communication Link: 

• Right click your receiver or transmitter and select the [Access] tool, which finds windows for line of sight between objects. Between communications objects, the Access tool also computes link budget and communications information. On the Access page, you can select the [Link Budget] button to generate the default link budget report. 

6. Review Results: 

• You can now review the link budget report you generated to determine the quality of the communications link based on the properties of your transmitter and receiver.  

• For more information on the data providers included in the Link Budget report, see the following help page: Report Style: Link Budget (agi.com)  

• There are other report styles available that can be generated by opening the Report and Graph Manager, selecting Object Type: Access, and viewing the installed styles. This includes a more detailed link budget report: Report Style: Link Budget - Detailed (agi.com)  

For more detailed instructions, you can refer to the STK Communications tutorials available on the AGI website.  help.agi.com/stk/#training/CommFundamentals.htm  

Hope this helps! 

Best, 

Drew