undefined | Better HN

0 pointsremram2y ago0 comments

"They said it does X but really it does X and the superset Y"

In other words, they were correct then?

0 comments

3 comments · 1 top-level

femto2y ago· 2 in thread

They are describing a situation in which a line-of-sight channel is replaced with a rich/complex channel: the exact conditions under which MIMO distinguishes itself from beamforming.

I'd say incomplete rather than incorrect, and the complete story is worth knowing as it makes the solution used more interesting.

obi1kenobi2y ago

(Author here.) Yeah, I get where you're coming from. Ultimately, this was an editing decision first and foremost.

Beamforming is cool and magical, and MIMO even more so. The post wasn't intended as a primer on wireless technology, just as a fun read for folks to enjoy. I tried to sprinkle in some nerd-snipe-quality technical detail and offer links for folks who might want to dig in, and MIMO is explicitly discussed in both the 802.11n and in the several links on beamforming I provided.

I barely managed to explain beamforming without that sidenote turning into a paragraph of its own. I don't think I could have done MIMO justice in a sidenote.

femto2y ago

I get where you're coming from too.

I felt the need to mention the difference as so many people equate beamforming with MIMO and claim that there is no difference, when in fact that difference, which Foschini discovered in 1996, is responsible for spatial multiplexing and the high WiFi data rates we enjoy. I figured the typical HN reader might be more technical and interested in the difference, or maybe not.

1 more reply

j / k navigate · click thread line to collapse