# How is tropospheric correction/effect generated in Skydel?

**URL:** https://learn.safran-navigation-timing.com/t/how-is-tropospheric-correction-effect-generated-in-skydel/455
**Category:** GNSS Technology
**Created:** [February 15, 2022, 5:05pm UTC](https://learn.safran-navigation-timing.com/t/how-is-tropospheric-correction-effect-generated-in-skydel/455 "2022-02-15T17:05:45Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![hongzhaozheng](https://yyz2.discourse-cdn.com/flex030/user_avatar/learn.safran-navigation-timing.com/hongzhaozheng/32/115_2.png) [@hongzhaozheng](https://learn.safran-navigation-timing.com/u/hongzhaozheng)
#### Post date: [February 15, 2022, 5:05pm UTC](https://learn.safran-navigation-timing.com/t/how-is-tropospheric-correction-effect-generated-in-skydel/455/1 "2022-02-15T17:05:45Z")

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Hi,

Can anyone explain how Skydel generates the tropospheric correction/effect on signals from satellite to ground UE? If in particular I chose Saastamoinen model, what is the magic hehind so that the tropospheric delay is automatically generated?

Kindly,  
Hongzhao Zheng

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### Author: ![Grace](https://avatars.discourse-cdn.com/v4/letter/g/f17d59/32.png) [@Grace](https://learn.safran-navigation-timing.com/u/Grace)
#### Post date: [February 16, 2022, 8:37pm UTC](https://learn.safran-navigation-timing.com/t/how-is-tropospheric-correction-effect-generated-in-skydel/455/2 "2022-02-16T20:37:58Z")

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Hi @hongzhaozheng,

The tropospheric effect is implemented in Skydel as a delay.  
For the Saastamoinen model, you can actually find the information on the literature.

Regards,  
Grace

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### Author: ![hongzhaozheng](https://yyz2.discourse-cdn.com/flex030/user_avatar/learn.safran-navigation-timing.com/hongzhaozheng/32/115_2.png) [@hongzhaozheng](https://learn.safran-navigation-timing.com/u/hongzhaozheng)
#### Post date: [February 16, 2022, 9:15pm UTC](https://learn.safran-navigation-timing.com/t/how-is-tropospheric-correction-effect-generated-in-skydel/455/3 "2022-02-16T21:15:16Z")

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Thank you @Grace for the reply. I did a little research about the Saastamoinen model already. To calculate the tropospheric delay, I assume that you have used some default values for the parameters in the Saastamoinen model, right? If I want to implement the tropospheric delay on the custom signal, I might want to use the same parameters Skydel used for fairness.

Kindly,  
Hongzhao Zheng