With regard to stepped frequency radar, what does it mean when we say that the transmitted signal is "demodulated in a quadrature sense"?

The property of interest in this kind of radar is the phase difference. We basically obtain a phase delayed version of the Tx signal on receiving.

How does "demodulating in I/Q sense" help convert the phase difference into distance information?

I understand basic digital I/Q modulation.

Any help is highly appreciated!


  • \$\begingroup\$ You're asking "how to do stepped Frequency Radar in IQ baseband", and that's really already answered in the literature you seem to have. Even if it's not, it's either too trivial (measure the beat frequency, done) or too broad (needing a complete introduction to radar). \$\endgroup\$ – Marcus Müller Aug 11 '19 at 13:54
  • \$\begingroup\$ @MarcusMüller: Dear Marcus, thanks for your comment. Actually I understand the basics of radar, but now I am trying to implement one on my own, that's why the questions! I am going through books which actually consider the development of prototype. \$\endgroup\$ – anildadj Aug 11 '19 at 16:45
  • \$\begingroup\$ Given I and Q versions of the desired modulation, you impose these onto the carrier, perhaps by upconversion after IQ combining. The combining provides all possible information-control modes. \$\endgroup\$ – analogsystemsrf Aug 11 '19 at 17:38