.. _sphx_glr_api_gallery_communications_multiplexing:

Multiplexing
------------

Orthogonal frequency-division multiplexing.


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    <div class="sphx-glr-thumbcontainer" tooltip="Robert Chang (1966) showed that subcarriers whose spectra overlap remain orthogonal if they are spaced by the symbol rate. Stephen Weinstein and Paul Ebert (1971) generated the whole set with a single inverse DFT (~engineeringkit.communications.ofdm_modulate) and prefixed each block with a copy of its tail. This cyclic prefix turns a dispersive channel&#x27;s linear convolution into a circular one, so after the receiver&#x27;s DFT (~engineeringkit.communications.ofdm_demodulate) every subcarrier sees one complex gain, removed by a single division. The idea now carries Wi-Fi, LTE and digital television.">

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  :doc:`/api/gallery/communications/multiplexing/plot_01_ofdm_cyclic_prefix`

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   /api/gallery/communications/multiplexing/plot_01_ofdm_cyclic_prefix