Introduction and Some History

  • Joachim SpeidelEmail author
Part of the Signals and Communication Technology book series (SCT)


Time-variant systems are of general interest, because they play an important role in communications due to the emerging wireless networks for in-house and outdoor applications. As a matter of fact, a wireless channel can change its parameters with time depending on the position of the mobile transmitter, the receiver, and on the change of the surroundings. During the education of electrical engineers, the main focus is on time-invariant systems and the topic of time-variant systems is not always strongly alluded. Thus, also from this perspective, a general view of time-variant systems and their mathematical description is favorable.


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Institute of TelecommunicationsUniversity of StuttgartStuttgart, Baden-WurttembergGermany

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