{"id":817,"date":"2026-06-07T09:59:57","date_gmt":"2026-06-07T07:59:57","guid":{"rendered":"https:\/\/www.i8zse.it\/en\/?page_id=817"},"modified":"2026-06-07T10:03:06","modified_gmt":"2026-06-07T08:03:06","slug":"multiplexing","status":"publish","type":"page","link":"https:\/\/www.i8zse.it\/en\/modulation\/multiplexing\/","title":{"rendered":"Multiplexing"},"content":{"rendered":"

From modulation to multiplexing: changing scale<\/h3>\n

After examining how modulation works\u2014whether AM, FM, SSB, FSK, PSK, ASK, QAM, or APSK\u2014one might think the picture is complete: we have the techniques that allow a signal to travel over a radio channel. In reality, everything discussed so far concerns a single information stream: one signal, one carrier, one modulation shaping its form and characteristics.<\/p>\n

But real-world communications almost never deal with just one stream. They must carry many, often simultaneously, often within the same band, sometimes even on the same frequency. This is where we move from the question how do we modulate a signal?<\/em> to a more fundamental one: how do we make multiple signals coexist without interfering with each other?<\/em><\/p>\n

This is a conceptual change of scale. Modulation<\/strong> defines how a single signal occupies a channel. Multiplexing<\/strong> defines how multiple signals share the same channel.<\/p>\n

If modulation is the technique used to shape the carrier, multiplexing is the strategy used to organize traffic. It does not replace modulation: it relies on it. Each multiplexed stream is still modulated in some way; what changes is how multiple streams are combined.<\/p>\n

At this point, multiplexing techniques come into play, exploiting different dimensions of the signal:<\/p>\n