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Comment by anfractuosity | Hacker News Reader

It says regarding CSS "That makes even faint LoRa signals easy to distinguish from background noise, which fluctuates randomly".

Is CSS better than FSK than in this respect or..?

Edit: http://www.akermann.bg/files/Semnrs/H2016/Module3.4_100km%20...

Says

"Spreading codes does not improve sensitivity over FSK systems, for usable datarates you get similar sensitivity using standard FSK modulation"

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>background noise, which fluctuates randomly

From years of experience selling, supporting, and installing 900MHz ISM radios, I can tell you this is not the case in many, many places (it describes a greenfield application more or less correctly, though). 900MHz is heavily used in the US and describing the noise as "background" or "random" is disingenuous at best. I'd like to see someone install a LoRa hub on a tower with several other 900MHz radios (common) and see how well it works.

That's very interesting cheers. Just to clarify that quote was from the article this post originally linked to, rather than the paper it now links to.

CSS is an analog (continuous frequency function) modulation where the CSS standard specifies that only linear encoding be used while FSK is a digital modulation that can employ pseudo-random keying and operates at discrete frequency keys. Without these restriction imposed by standards, FSK would be a special case of CSS, at least mathematically.

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