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new study recommends 38 GHz for Wireless power transmission - RF Cafe Forums

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 Post subject: new study recommends 38 GHz for Wireless power transmission
Posted: Sat Jul 18, 2009 12:24 am 

Joined: Wed Oct 17, 2007 1:03 pm
Posts: 5
Location: Oregon, USA
Financial and Organizational Analysis for a Space Solar Power System - Toulouse, France

A ground-breaking new paper on space solar power has just been added to the online NSS Space Solar Power Library. The paper is: “Financial and Organizational Analysis for a Space Solar Power System,” May 18, 2009, 225 pages, 3.7 MB PDF.

Lt. Col. Peter Garretson, NSS Director and one of the principal authors of the Department of Defense report Space-Based Solar Power As an Opportunity for Strategic Security writes:

“This is the first modern paper to include a stakeholder analysis, an in-depth discussion of international organizational aspects (including intellectual property and separation of manufacture and operator companies), and Net Present Value calculations of niche systems (such as front-line military power).”

Authors of the paper are Sun Xin, IT Director of the China Academy of Space and Technology; Evelyn Panier, Finance Application Consultant; Cornelius Zund, Control Systems Engineer at Pratt & Whitney Canada; and Raul Gutierrez Gomez, Lieutenant Colonel in the Colombian Air Force and Planning Director of Military Aeronautical Institute.

The paper was a multicultural team project submitted in partial fulfillment for the degree of Master of Business Administration in Aerospace Management at Toulouse Business School, Toulouse, France.

This entry was posted on Thursday, July 16th, 2009 at 9:35 pm and is filed under David Brandt-Erichsen, NSS Website Updates, Space Solar Power. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

Selected quotes:

"There is a minimum of atmospheric signal attenuation in the range of 2.45-5.8GHz, and also 35-38GHz. Specifically we might expect losses of 2-6%, and 8-11% respectively. We will use a transmission frequency of 38GHz since this allows us to transmit the most energy into the smallest space, even when accounting for transmission losses."

"7) We will use a transmitter diameter of 141m. 8) The combination of transmitter size and frequency result in a relatively small rectenna diameter when compared against the ESA reference system"

"Linked to the cost of the launcher is the needed mass of the system. The satellite mass value of 3137Kg/Tm used in our calculations added a considerable amount of mass for larger transmitter diameters, leading us to select a higher frequency of transmission (38GHz). This choice allowed us to afford a smaller antenna / rectenna combination, however substantially increased energy transmission density. The diffuse energy density offered with a 2.45GHz system required a massive increase in rectenna size, and offered no benefits in terms of cost."

 Post subject: Re: new study recommends 38 GHz for Wireless power transmission
Posted: Sat Jul 18, 2009 11:31 am 

Joined: Sun Jan 11, 2004 4:44 pm
Posts: 22
Here's a useful paper for you.

Analysis of Zincblende-Phase GaN, Cubic-Phase
SiC, and GaAs MESFETs Including a Full-Band
Monte Carlo Simulator

The Friis equation predicts 215 dB of attenuation over 22,000 miles (geostationary altitude) at 38 GHz. That is for 0 dB gain antennas. So 1 megawatt of 38 GHz power in geosynchronous orbit gets you 0.31 femtowatts on Earth. Using a huge Earth-based collector for aperature gain certainly helps, but that's a big antenna.

It seems absolutely ridiculous to me that we are considering these outlandish schemes with all the energy and logistics required to deploy them, when unlimited, clean, 0-carbon-footprint nuclear power is available today. Even billionaire T. Boone Pickins is abandoning his $1B investment in wind turbines because his brainiacs forgot to tell him that it wouldn't be so simple tying them into the power grid. Oops. :smt102

Put the effort into making it more safe and in disposiing of the spent fuel.

 Post subject: Re: new study recommends 38 GHz for Wireless power transmission
Posted: Thu Jan 07, 2010 8:35 pm 

Joined: Tue Apr 11, 2006 8:13 pm
Posts: 44
Just out of curiosity...Though atmospheric loss (sky clear condition?) might be small at 35GHz, those frequencies are prone to attenuation through clouds. Would it really be really cost effective to use that band for power transmission?

Posted  11/12/2012