Some materials return larger radar signals than others.

Liquids, solids, and powders found in the chemical industry don’t easily reflect radio waves. A moving car, however, does.

Radar technology is used in a variety of applications. Long-rang radar, for example, detects military threats and supports air-traffic control. Short-range radar can be used in automotive applications like collision avoidance, driver assistance, and, if in the hands of a police officer, getting you pulled over for speeding.

Radar systems frequently employ continuous wave (CW) signals. CW radar applications can be simple, like the unmodulated Doppler speed sensing systems used by law enforcement. More specialized applications, like missile homing or naval scenarios, may call for modulated CW radar.

Dynamic range refers to the span of usable signals that a device can detect. The larger a radar instrument's dynamic range, the smaller the signals it can measure.

The most sensitive radar sensors on the market have a dynamic range of about 120 dB, or decibels.

So how do you know what you need your dynamic range to be?

Alex Krauska, Tektronix

In a Tech Briefs presentation titled Radar Measurements: Triggering, Analysis, and Generation, a reader asks Alex Krauska, RF Solutions Architect at the Beaverton, OR-based T&M manufacturer Tektronix.

"How do I know how much dynamic range I need?"

Read Krauska's response below.

Krauska: This is always a tough question because some waveforms are intentionally spreading themselves so they’ll occupy a wide bandwidth, but the peak power at any given moment is going to be quite high. So on a spectral type display, they might look like a small signal, but they’re a bit like a watering can sprinkling spectral energy across a wide range.

You have to consider your spectral spreading in terms of db reduction from the CW carrier, and the ratio between your largest signal and your smallest signal that you might that you might want to measure: for example, if you’re reading to detect radar emissions in a non-allowed band and want to make sure that your radar is compliant with necessary requirements for missions.

Have more questions? Share your comments below.