| General > General Technical Chat |
| Tesla teardown finds electronics 6 years ahead of Toyota and VW |
| << < (14/14) |
| coppice:
--- Quote from: Marco on February 20, 2020, 10:45:32 pm --- --- Quote from: coppice on February 20, 2020, 09:08:14 pm ---How would you expect to build a narrow beam scanning radar at consumer prices? --- End quote --- How about we just give up radar and time of flight? Make 60 GHz cameras with a rectenna array and a metamaterial lens, plus a continuous 60 GHz beam for illumination. Naive ToF systems are sensitive to interference and complicated systems are hard to do at high resolution. A camera though has a simple structure and with stereoscopy can see depth just fine. --- End quote --- I don't know if they use ToF or some variant of FM. My go to approach would be to transmit fairly wide band noise, and correlate the transmitted and received signals. |
| Marco:
--- Quote from: coppice on February 20, 2020, 10:49:58 pm ---I don't know if they use ToF or some variant of FM. My go to approach would be to transmit fairly wide band noise, and correlate the transmitted and received signals. --- End quote --- My point was that to do that for a ton of pixels is hard ... the only alternative is to do it very fast and scan, but it's hard to get a tight beam with phased arrays and mechanical scanning is expensive and fragile. A 60 GHz camera has a comparatively simple structure. |
| thinkfat:
--- Quote from: coppice on February 20, 2020, 09:08:14 pm --- --- Quote from: thinkfat on February 20, 2020, 08:50:53 pm ---I thought there would at least be a little beamforming and directing involved, with a phased antenna array. I can't believe it'd work otherwise. Imagine overtaking a truck while the road turns left. If the radar was always looking straight ahead, you'd get a collision warning. Yet, that is not what is happening. The radar seem to look along the road. --- End quote --- If you look at the specs for most of the car radars they have two transmissions, working concurrently in different bands, with different beam widths. A fairly wide beam, and a very wide beam. How would you expect to build a narrow beam scanning radar at consumer prices? --- End quote --- Since the antennas are anyway a phased array (no space for something else), I can imagine that at least skewing the beam to "look" left and right, or/and the receiver pattern doing the same is possible. Anyway, you'd not have to create a narrow, scanning beam. It's enough to vaguely look in the direction of the turn to suppress unwanted reflections from targets not in you lane. |
| Navigation |
| Message Index |
| Previous page |