Earlier today, I was listening to my digital radio, and was intrigued as to how they are able to encode the information displayed on the LCD screen (which was basically a short string of text giving a brief description of the currently playing record/discussion topic), alongside the audio transmission.
My question is:
How is extra information (such as "currently playing song"), transmitted alongside the audio in digital radio encoding?
I am somewhat familiar with the workings of a radio, along with some basic understanding of RF-transmission, but nothing particularly advanced. And I was intrigued as to how they can transmit information within the same bandwidth of the audio transmission without causing interference. My first thought was that they could polarize both text and audio transmissions so their planes of oscillation are orthogonal to each other, and thus no interference would occur, but I didn't know how plausible that would be.
Thanks in advance, apologies if this a stupid question.