##  [Reciprocity Theorem](/reciprocity-theorem) 

  ##  [Reciprocity Theorem](https://information.quantumdictionary.io/reciprocity-theorem-0) 

  

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**Information & Communication Dictionary**

 







 

 

 

 



 

 

 

 

Definition

In linear, passive, time‑invariant and non‑magnetized electromagnetic media (reciprocal media), the transfer relation between two points or ports is symmetric: the response (field, voltage or scattering parameter) measured at point B due to a source at A equals the corresponding response at A when the same source is placed at B, under the same loading and excitation conditions.