The distinction between analog and digital signals is very simple, but it can still be a challenge to wrap one's mind around the concepts that define the two systems. Just when you think you've got it ...

Wide bandwidth radio transmitters commonly use analog quadrature modulators (AQMs) to convert complex (I + j*Q) baseband signals to radio frequencies (RF). An AQM consists of a local oscillator (LO) ...

In a special report late last year we explored the fairly recent discovery of inadvertent “capture” of out-of-market HD digital radio signals by receivers tuned to local stations on the same frequency ...

Analog radio broadcasts are pretty simple, right? Tune into a given frequency on the AM or FM bands, and what you hear is what you get. Or at least, that used to be the way, before smart engineers ...