Tren Griffin @trengriffin I work for Microsoft. Previously I was a partner at Eagle River, a private equity firm established by Craig McCaw. I am on the board of directors of Kymeta. Sep. 15, 2019 1 min read

If your device (e.g. iPhone 11) uses ultra-wide band (UWB) it: (1) operates at power levels below the noise floor; and (2) uses spectrum that occupies a bandwidth greater than 500 MHz. Low power spectral density limits interference with conventional radio.  https://www.itu.int/dms_pubrec/itu-r/rec/sm/R-REC-SM.1755-0-200605-I!!PDF-E.pdf 

Radio involves trades: "UWB trades pulse shortness (gaining high signal/symbol rate) in exchange for 1) bandwidth (which becomes wider) and 2) S/N (which is reduced). Each advantage is offset by a disadvantage, the cure for which is another disadvantage."  https://www.ntia.doc.gov/legacy/osmhome/uwbtestplan/barret_history_(piersw-figs).pdf 

Relatively low power limits allowed in use of UWB are both a disadvantage and a benefit since they: 1) restrict applications to relatively short distances, but 2) result in a very power-efficient and low-cost implementations, which preserves battery life.

As in most aspects of life, tradeoffs are inevitable. An ideal wireless system would transmit:

1. a lot of data,
2. very far,
3. very fast,
4. for many users,
5. all at once.

It is impossible to achieve all five attributes simultaneously. C’est la vie.  http://ecee.colorado.edu/~ecen4242/marko/UWB/UWB/art_4.pdf 


You can follow @trengriffin.



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