Google is building an 100 kW transmitter. - Page 1
Forum section: electronics / general

author: firewalker
author_rank: Super Contributor
timestamp: March 03, 2016, 08:05:34 pm
content: https://hackaday.com/2016/03/02/google-is-building-a-100kw-radio-transmitter-at-a-spaceport-and-no-one-knows-why/Alexander.

author: XOIIO
author_rank: Super Contributor
timestamp: March 03, 2016, 08:13:29 pm
content: Mind control.

author: rolycat
author_rank: Super Contributor
timestamp: March 03, 2016, 08:20:38 pm
content: With the headline hyperbole removed:Google is building a highly directional 0.5 watt transmitter and it's likely to be an experiment aimed at faster communications.

author: PA0PBZ
author_rank: Super Contributor
timestamp: March 03, 2016, 08:25:19 pm
content: Quote from: rolycat on March 03, 2016, 08:20:38 pmExactly, a 0.6M dish will do that.

author: Zero999
author_rank: Super Contributor
timestamp: March 03, 2016, 08:49:51 pm
content: Yes, where the heck did they get the 100kW from if it's only 0.5W?

author: thm_w
author_rank: Super Contributor
timestamp: March 03, 2016, 09:26:24 pm
content: Quote from: Hero999 on March 03, 2016, 08:49:51 pmQuoteQuotehttps://en.wikipedia.org/wiki/Effective_radiated_powerIts an accepted industry term but applying it to narrow beams seems ridiculous and misleading.

author: RobertoLG
author_rank: Frequent Contributor
timestamp: March 03, 2016, 10:24:13 pm
content: or comunication with aliens lol

author: TheSteve
author_rank: Unknown
timestamp: March 03, 2016, 10:45:38 pm
content: Perhaps they plan to put a couple hundred thousand transceivers in space and run millimeter wave micro spotbeams all over the place. I don't see them using millimeter wave for any LEO applications though.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 04, 2016, 11:11:54 am
content: ERP is the same reason one 20mA red superbright LED can be 100mcd or 50,000+.Tim

author: rs20
author_rank: Super Contributor
timestamp: March 04, 2016, 12:03:27 pm
content: Quote from: thm_w on March 03, 2016, 09:26:24 pmWhy? If you're sitting (or flying through) the beam, the ERP tells you exactly what you'll experience right there. Like T3sl4co1l points out, it's just like with LEDs. You can tell me all you want that the 50,000mcd LEDs are "misleading" because they put out the same number of lumens as a 100mcd LED, but you'll be singing tune if you stare down the barrel of one.

author: thm_w
author_rank: Super Contributor
timestamp: March 04, 2016, 10:18:27 pm
content: Quote from: rs20 on March 04, 2016, 12:03:27 pmIt tells you nothing about what you'll experience right there, without knowing radiation pattern and distance.If you say 0.5W then you know that at most you would see that much power.mcd is also useless unless beam angle is given as well.

author: uncle_bob
author_rank: Unknown
timestamp: March 05, 2016, 12:46:38 am
content: HiUsing EIRP to confuse a 100KW device with a 0.5W device is one good example where EIRP leads one astray.Bob

author: vk6zgo
author_rank: Super Contributor
timestamp: March 05, 2016, 09:08:17 am
content: Quote from: uncle_bob on March 05, 2016, 12:46:38 amAnd the amazing thing is that people who post on an EE forum & would laugh ideas of "over-unity" devices to scorn,still get sucked in by it.If EIRP actually gave real power gain,our energy crisis would be over.Bob,"they're all mad,but me & thee---& I'm not too sure about thee!"

author: rs20
author_rank: Super Contributor
timestamp: March 05, 2016, 12:36:57 pm
content: Quote from: thm_w on March 04, 2016, 10:18:27 pmIf you place a photodetector in the brightest part of an LED's beam, the reading it registers can be found using mcd rating and distance alone. No need for radiation patterns. This is thewhole pointof the mcd unit.If you place an RF detector at the "brightest" part of a satellite dish's radiation pattern, the readings you'll read are given by ERP/EIRP and distance alone. This is thewhole pointof ERP/EIRP.Quote from: uncle_bob on March 05, 2016, 12:46:38 amThat's dumb journalists confusing EIRP with power. If people stated EIRP in W/sr, that'd be fine to dissuade journalists from misusing it. But then it'd be harder to use for people working from dipole/isotropic formulae.

author: profany
author_rank: Contributor
timestamp: March 06, 2016, 07:04:25 pm
content: wow, thats amazing