Nanoscopy describes the ability to see beyond the generally accepted optical limit of 200–300 nm. Stimulated emission depletion (STED) microscopy, developed by Stefan W. Hell and Jan Wichmann in 1994, ...

The need to translate frequencies up or down is a basic signal-chain need. The key component used to do this is the mixer, which essentially multiplies two signals together. In the frequency domain, ...

Figure 4. A snapshot, in time, of two complex numbers whose exponents, and thus their phase angles, change with time. The notion of negative frequency is often troubling to engineers who've spent so ...

Modern oscilloscopes capture, view, measure, and analyze complex RF signals in the time, frequency, and modulation domains. Time-domain analysis, the original oscilloscope function, allows users to ...