##  [Link Margin](/link-margin) 

  ##  [Link Margin](https://information.quantumdictionary.io/link-margin-0) 

  

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**Information & Communication Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The excess signal level available above the minimum required level to achieve a target performance (e.g., target BER or SNR) under varying conditions, usually expressed in decibels. In a link budget, link margin = measured or predicted received power (or SNR) − required power (or SNR) for the target performance; it quantifies robustness to fading, shadowing, aging and model uncertainty.