5 ms·
Skolnik's books are good but they are pretty old and focus mostly on the hardware/transmission of radar. The code sequencing is on the baseband signal processi
by Junk_Collector 8y ago
Skolnik's books are good but they are pretty old and focus mostly on the hardware/transmission of radar. The code sequencing is on the baseband signal processing side and is a direct result of IQ modulation being a thing in vector signal processing. Lots of modern radar designs use the same style of pseudo-random encoding to prevent interference between units. It's a major push in automotive radar right now (70GHz band) for instance.
Think of it as encoding your mac address on each packet you transmit wirelessly so you can tell which signals come from which source.
- vonmoltke 8y agoI don't recall such a scheme being used on either system I worked on. However, skimming the paper in your sibling's post it would be something done in the RF front end, which is probably why I never encountered it. The closest I got to the front end was pseudo-raw IQ from the pulses. It was also probably tied up in the anti-jamming measures, so it wouldn't get wide circulation on the programs.
- Junk_Collector 8y agoYes it's predominately a base band technique, although it has also been written about a fair bit in literature as an efficient power spreading alternative to a classic chirp. In that case, it is predominantly done to help propagation leveraging the extensive work done in communications on "noise-like" signals. In the case of Automotive radar, using it as an identifier to prevent interference is appealing because it allows each radar to use the full 6 GHz of channel bandwidth which greatly improves the performance of the radar despite the fact that there are tons of same channel independent devices operating. Each one would effectively be a jammer otherwise.