pps43 · HackerTrans

Combat iPhone is ok only in asymmetric warfare. Near-peer adversary will quickly figure out how to exploit it. Russia has already successfully targeted artillery strikes using location of Ukrainian soldier's phones (Android, but this difference is not very important).

pps43

10年前讨论

Processing power is not a problem these days. Maybe if you feed all channels at ultrasound frequency to ADC and then try to do all processing in software. But you don't have to, it's oftentimes easier to have hardware (FPGA) pseudorandom signal generators and correlators to do the bulk of signal processing for you.

pps43

10年前讨论

The reasons ultrasound machines are expensive are not technical, it's mostly low volume and high overhead to comply with all rules and regulations.

You can make a useful ultrasound machine with just one transducer (e.g., to measure blood flow through the heart using Doppler, or using mechanical scanning).

You don't need fast CPU for processing, just downconvert to audio range and then 80286 is fast enough.

Source: wrote embedded software for one of those machines back in the day. 16 kB for everything, from keypad debouncing to GUI.

评论