mstresh

4 ms·

1.
by mstresh 6y ago
One interesting way that fibers are not immune to RF noise is in the presence of lightning strikes [1]. The strong electromagnetic fields can cause a polarization rotation inside the fiber, which the DSP at the receiving end of coherent lin
2.
by mstresh 6y ago
Hi Chris, I just saw your show today and had a good time. Keep it up!
3.
by mstresh 6y ago
Spectral efficiency is also a nifty metric because, given some bandwidth and signal-to-noise ratio, there is an upper bound to which you can compare a result [0]. Frequency spacing makes sense as namibj points out. Most long-distance teleco
4.
by mstresh 6y ago
Figure 3 in this open-access paper [0] provides historical scaling trends in optical fiber communication (transport) compared to generation and processing. Depending on the time period under study, bandwidth increases at between 20% and 100
5.
by mstresh 6y ago
Howdy, I design optical integrated circuits for coherent communication. mmmBacon is correct. See here[0] or [1] for examples of the types of forward error correction used in coherent links. Pre-FEC bit error rate thresholds of 1e-3 or 2e
6.
How an entire nation became Russia's test lab for cyberwar(wired.com)
4 points by mstresh 9y ago|0 comments
7.
by mstresh 9y ago
About using light: I don't believe light will replace the transistors performing logic except in a few niche applications (e.g. [1]). Light is physically constrained by it's wavelength. It's difficult to build interacting
8.
by mstresh 9y ago
I think it's great that a data center operator is willing to relax their requirements. For too long we've been designing against telecom specs and operating environments. I think in order to bring more OEM vendors in we need to se
9.
by mstresh 9y ago
I'm also curious what the pricing difference is for a CWDM4 transceiver and the OCP version. I would guess the NRE to develop either is similar and that the design for either is almost the same. Perhaps Facebook is just trying to get t
10.
by mstresh 10y ago
Put it the other way: what would be the benefit of publicly disclosing their secret sauce? Perhaps to help fuel their recruiting pipeline, but I can't think of any other good reasons to do so. They don't have a product out, their
11.
by mstresh 10y ago
The Watts group at MIT has done some fantastic work into rare-earth doped silicon waveguides to produce lasers on a silicon platform [0]. However, I believe this work is still very much in the research stage. I'm not convinced their
12.
by mstresh 10y ago
I believe that LIDAR will be to silicon photonics what the accelerometer was to MEMS. The real challenge that the article only touched upon is to get lasers into the same package and keep the costs down. This is still an active area of pur
13.
by mstresh 10y ago
Efficiently directing light into a fiber optic cable is a difficult problem, in general. The luminescence is their proposed solution to this problem and one of the key results in their journal article. You have to shine light end-on into a
14.
by mstresh 11y ago
Yes, an interferometer is certainly a very common method to perform switching. What ultimately gets used will depend on the technology/material system. Silica-on-silicon and silicon photonics-based switches will likely use Mach-Zehnd
15.
by mstresh 11y ago
Generally speaking, being able to split based on wavelength lets you transmit data on multiple wavelengths to increase your bandwidth. The flow is to modulate each wavelength individually, mux them together, send them through a single fiber
16.
by mstresh 11y ago
I did my PhD work in silicon photonics (in a different lab group and not associated with the authors in the paper) and thought I could chime in with some extra background and why this result is interesting to the silicon photonics community