3 ms·
You need to poll many frequencies at once, very quickly, in order to make a missile that can respond fast enough. Maybe it's possible with a very wide SDR, but
by chisleu 11y ago
You need to poll many frequencies at once, very quickly, in order to make a missile that can respond fast enough.
Maybe it's possible with a very wide SDR, but I've not seen one where it was.
- cnvogel 11y agohttp://www.gnss-sdr.org/ http://www.gnss-sdr.org/ claims to be able to work with RTLSDR dongles (cost ~$10 and provides 3,2 MHz Bandwidth. Original article's "homemade GPS" has 2,5 MHz BW). Also: http://www.rtl-sdr.com/tag/gps/ http://www.rtl-sdr.com/tag/gps/
- chisleu 11y agoDoing it, and doing it fast enough to guide a missile at > mach 2 are different things entirely. The rate that you have to constantly be calculating the spin (if any) and the vector and speed is incredible. OTS 5-10hz refresh will not cut it. That said OTC stuff is so dangerous now that I think we should roll back the laws to allow home lab/hackerspace science to evolve. I would love to launch a rocket from weather balloons, but it would stand little chance of getting anywhere with OTS GPS gear.
- toomuchtodo 11y agoI'd agree with you. I'm probably mistaken that in-software SDR can decode GPS fast enough. I would argue though that ASIC manufacturing costs are coming down fast enough that you could ship out your hardware design for a GPS system without ITAR altitude/speed limitations and have a finished product back in your hands in 7-10 business days.