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admin Site Admin
Joined: 03 Jan 2007 Posts: 201
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Posted: Mon Aug 01, 2011 4:42 am Post subject: Raytheon Develops Miniature Antenna For Unmanned Aircraft Sy |
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Raytheon proudly announced they have developed a miniature antenna for unmanned aircraft.
Here's the thing:
1) Raytheon develop an antenna that is about 1" cubed
2) They say it weighs a fraction of an ounce
3) Operates at millimeter wave frequencies
Ok, so 1" is 25.4 mm. If the wavelength is mm, why is it difficult to place an antenna in such a volume? In fact, it should be trivial. How is this an advancement? Further, in regards to the weight - antennas can be made from thin foil, so how is this an accomplishment?
In summary, this announcement sounds like they did something. But I believe they charged the US government 10-100 million dollars for something a competent antenna engineer could do in a few hours.
Am I wrong? I'd love to hear why what they did was difficult. Article reference below.
http://avstop.com/news_august_2011/raytheon_develops_miniature_antenna_for_unmanned_aircraft_systems.htm |
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britny.mark Antenna-Theory.com Newbie
Joined: 16 Nov 2013 Posts: 1
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Posted: Sat Nov 16, 2013 11:16 am Post subject: |
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have a trivial question: in the short dipole (L<<lambda)
the current distribution on the wire is triangular. That means that the current is flowing in the same direction at every instant of time but it is locally different in strength. At exactly half a cycle in time the current is everywhere zero. After half a cycle, the current change direction.....
Is this current distribution representing a current standing wave or is it a traveling current?
The sign of the current represents its direction which induces me to thing that it is flowing....but then it cannot be a standing wave if it is flowing....
Thanks
tensor20 |
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cnmcdee Antenna-Theory.com Newbie
Joined: 12 Apr 2015 Posts: 2
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Posted: Mon Apr 13, 2015 7:29 pm Post subject: Re: Raytheon Develops Miniature Antenna For Unmanned Aircraf |
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admin wrote: | Raytheon proudly announced they have developed a miniature antenna for unmanned aircraft.
Here's the thing:
1) Raytheon develop an antenna that is about 1" cubed
2) They say it weighs a fraction of an ounce
3) Operates at millimeter wave frequencies
Ok, so 1" is 25.4 mm. If the wavelength is mm, why is it difficult to place an antenna in such a volume? In fact, it should be trivial. How is this an advancement? Further, in regards to the weight - antennas can be made from thin foil, so how is this an accomplishment?
In summary, this announcement sounds like they did something. But I believe they charged the US government 10-100 million dollars for something a competent antenna engineer could do in a few hours.
Am I wrong? I'd love to hear why what they did was difficult. Article reference below.
http://avstop.com/news_august_2011/raytheon_develops_miniature_antenna_for_unmanned_aircraft_systems.htm |
"Raytheon's Cooperative Target ID is an electronic "question and answer" Ka band radio technology. Highly directional, it employs low radiated power, encryption, advanced signal processing and spread spectrum techniques for clandestine full-spectrum contingency operations. The technology is designed for ease of use and integration with modern surveillance and targeting systems and can reliably identify equipped friendly forces in less than one second at long ranges and well within the normal target engagement cycle."
- Highly directional in a device that is moving and axis shifting would probably exhibit some phased array capabilities in this little cube. I do not think that is easily engineered in something the size of a quarter. |
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