awelkie
Joined 9 years ago
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327
Submissions
79
Member since
Apr 13
Recent submissions
Comment · 11 months ago
Comment · 1 year ago
I think the miserable state of cellular modems ultimately comes from the power dynamics of private spectrum. The 3GPP protocols are complex because they're not really beholden to the implementers, but rather to the network operators. The operators are fine with additional complexity if it serves their interests, and the cost will just be passed on to the OEMs. The network operators have all the power because they're the ones with the licenses.
WiFi tends to be simpler in part because the protocol authors are working more in the interest of the implementers, since it's really they who decide whether to adopt or not. Obviously a gross simplification but I think it's at the heart of the problem.
Comment · 1 year ago
Sure, but the probability would be low-ish of that happening, and the other system could either switch frequencies or beamform a null in the direction of the interferer if they were also a phased array.
Maybe the EIRP shouldn't be unlimited, but I still think it would be beneficial to encourage spatially selective systems.
Comment · 1 year ago
I feel like limits on EIRP are overly conservative and restrict the usefulness of phased arrays. If the limit were on total radiated power, then your 1 watt WiFi router could have the range of a kilowatt transceiver with a reasonable number of antenna elements, while emitting the same total power as interference. But since the limit is on EIRP, the phased array is limited to the same range, and so there's no point in using a phased array over a single antenna.
Does anyone know if there's a good reason to use EIRP that I'm missing? I figure satellite communication terminals can have huge EIRPs because they're all pointed at the sky, but the FCC can't guarantee that the beams won't cross for other bands, so they limit the EIRP, but I still think we would all be better off of our systems were spatially selective.
Comment · 2 years ago
Good point. To my knowledge most of these radars are MIMO, which are more capable than phased arrays but it's a different architecture. Also these radar systems usually have on the order of 10 antenna elements (although this number is increasing), whereas the starlink terminal has something like 1000 antenna elements, if I remember correctly.
Comment · 2 years ago
Starlink doesn't get enough credit for their phased arrays terminals, I think. They've managed to make a performant antenna for 10 to 100 time less cost than the competition. Without that, the whole system wouldn't be such a success. This article goes into some details. It's the first truly mass produced RF phased array, and the fact that they've shown it's possible will have some big impacts on certain fields (SATCOM obviously, mobile networks, etc).
https://lilibots.blogspot.com/2021/01/why-is-starlink-termin...
Comment · 3 years ago
Step two is not even necessary if you use zero-to-nix's installer. https://zero-to-nix.com/start/install
Comment · 3 years ago
Greenerwave | https://greenerwave.com | Paris, France | Full Time | VISA | ONSITE
Founded in 2015 and spun-off from the Langevin Institute (CNRS and ESPCI), Greenerwave is a mission-led GreenTech, specializing in reconfigurable metasurfaces (smart electronic surfaces) and EM wave control (from 1GHz to 77GHz). We create innovative, energy-efficient, and "plug & play" solutions. We develop patented technologies that are recognized worldwide (PACEPilot Award 2022, member of ETSI and 3GPP ...). We work on several projects with large industrial partners as well as the state and military. Our disruptive technology allows us to design solutions in telecommunications, NewSpace (SATCOM, 5G-6G) as well as in detection (RADAR, RFID).
With more than 50 employees, we're still hiring across many projects and many areas of expertise. We're looking for RF Engineers, Embedded Software Developers, Hardware or FPGA Engineers, Mechanical Engineers, Physicists, and Signal Processing Engineers.
At Greenerwave, you'll have the opportunity to evolve in a field that will have an impact on the future and work with many passionate experts (PhDs, Engineers) from all over the world on complex solutions.
Please send your resume to [email protected]
Comment · 3 years ago
Greenerwave | https://greenerwave.com | Paris, France | Full Time | VISA | ONSITE
Founded in 2015 and spun-off from the Langevin Institute (CNRS and ESPCI), Greenerwave is a mission-led GreenTech, specializing in reconfigurable metasurfaces (smart electronic surfaces) and EM wave control (from 1GHz to 77GHz). We create innovative, energy-efficient, and "plug & play" solutions. We develop patented technologies that are recognized worldwide (PACEPilot Award 2022, member of ETSI and 3GPP ...). We work on several projects with large industrial partners as well as the state and military. Our disruptive technology allows us to design solutions in telecommunications, NewSpace (SATCOM, 5G-6G) as well as in detection (RADAR, RFID).
With more than 50 employees, we're still hiring across many projects and many areas of expertise. We're looking for RF Engineers, Embedded Software Developers, Hardware or FPGA Engineers, Mechanical Engineers, Physicists, and Signal Processing Engineers.
At Greenerwave, you'll have the opportunity to evolve in a field that will have an impact on the future and work with many passionate experts (PhDs, Engineers) from all over the world on complex solutions.
Please send your resume to [email protected]
Comment · 4 years ago
I live pretty far from my parents, and I really want to set them up with a nice video conferencing setup so we can chat as well as in person. I started to spec out a nice setup with open-back headphones, 60 Hz 1080p camera, nice microphone, low latency screen, the works. But this would cost at least $1k, and I'm sure it would be difficult for them to operate. Plus it would be hard to use in certain situations like with children or while eating.
So I've decided to get them the iPad Pro. I'm trusting Apple to focus on things like screen latency and microphone/speaker quality in their products. Plus it should be quite easy for my parents to use. It just seems to me like the iPad Pro is the best product for setting up non-tech people with a decent videoconferencing setup.
Has anyone else solved this problem, or have thoughts on using an iPad for video chatting?
Comment · 4 years ago
Having just skimmed the linked tutorial, it looks like GFlowNets could be useful for automated theorem proving. Anyone with more knowledge know if this is possible?
Comment · 5 years ago
I found some answers here: https://www.ycombinator.com/library/4r-yc-and-hard-tech-star...
Comment · 5 years ago
It's easy to see how this advice applies to a SaaS company, but what about a more capital-intensive startup? Like a startup with an innovation in manufacturing, energy, telecoms, how do they have leverage when approaching investors, especially at the beginning? Are patents the main way or are there others? What metrics can they show if they're working on a proof-of-concept and don't yet have customers?
I don't doubt that the advice still applies but I'm having a hard time understanding how. Are there illustrative examples of startups that did this well?
Comment · 5 years ago
Not only that, but the matrix scanning could be done via interrupts instead of via polling as is typically[0] done. An interrupt could fire on a level shift of any of the column GPIOs, then the MCU needs to search the rows to find the selected key. After the interrupt the MCU will need to poll until all the keys are released. So there's another source of latency that could be improved.
I think the only source of polling left is in USB, but I think that's inherent to the USB protocol (someone correct me if I'm wrong here). Without the USB polling I think it would be possible to have key-press-to-USB-packet completely interrupt driven which should make the latency in the keyboard itself negligible.
[0]: I say typically but like you said a lot of implementations are closed source, so who knows. All of the discussions I've seen on matrix scanning use the polling method, and the open source implementations use polling as well (e.g. Keyberon[1]).
[1]: https://github.com/TeXitoi/keyberon-grid/blob/master/src/bin...
Now personally I don't think this ultimate vibe-coding paradigm is just around the corner, but it does seem that it's the direction we're heading and I think this article does a good job of explaining why.