RF Shorts for Nov. 24, 2014

Farewell to 'Elephant Cages'

If you'd driven along the southern route towards Coronado island in San Diego you might have caught a glimpse of part of a huge antenna structure on the left. Viewed from above you'd see it was a circular array of wire antenna elements given the nick name “elephant cage.” It was one of several AN/FLR-9 antennas that were part of the Department of Defense's Wide High Frequency Direction Finding System. Read more about the antenna the GlobalSecurity.org AN/FLR-9 web page.

The San Diego elephant cage was retired in September. See the U-T San Diego article Navy's mysterious 'elephant cage' retired for details on the antenna I first saw over 30 years ago when checking the signal from KSCI's Mount Woodson translator.

I was reminded of this encounter when I saw a recent article on medium.com The U.S. Air Force is Tearing Down a Giant Spy Antenna – 'Elephant cages” are a dying breed. The article, posted last month by Joseph Trevithick, reports on the dismantling of one of these antennas at Misawa Air Base in Japan. It appeared after a U.S. Air Force article Iconic 'Elephant Cage' laid to rest.

That article has this quote from Col. Joseph Winters, a 373rd Intelligence, Surveillance and Reconnaissance commander: “While it performed its mission well for 48 years, outlived technology and fiscal constraints have driven Misawa Security Operations Center to seek new ways of doing business. "This massive structure has architecturally graced the northern skyline overlooking Lake Ogawara and is said to be considered a symbol of luck by the local Japanese. The Elephant Cage was undoubtedly part of Misawa's past and present, and it will be missed.”

Anyone who has looked on an iconic antenna structure will understand that sentiment. Col. Andrew Hansen, the 35th Fighter Wing vice commander, said, “During its long life the antenna played a major part in the Cold War and beyond. However, the technology has outlived its usefulness and requires new ways of operating. The demolition of the Elephant Cage marks the end of an era.”

Trevithick's article has more on this history of these antennas, including the origin of the name along with some great pictures of the antenna. The name, reportedly, came from Chief Master Sgt. Josepth Rabig, according to D.D. Kavanagh, a retired member of the Pacific Electronic Security Division, according to the American Scientists' website. “Joe came up with the explanation that it was an 'elephant cage.' He maintained that was their purpose and justified the explanation by pointing out [that] 'they work pretty well, don't they? You don't see any elephants running around loose, do you?'”

UHDTV Winning Battle in Korea for 700 MHz Spectrum

Sa Youn Hwang, in the article Ultra HD TV or mobile data: The fight for spectrum in Korea on CNET.com, writes that “Lawmakers in South Korea are siding with using the 700MHz frequency for nationwide Ultra HD broadcasts, instead of using the spectrum to relieve congested mobile traffic.” Korea's three major TV broadcasters, KBS, MBC and SBS, argued that 100 MHz spectrum in the 700 MHz has to be dedicated to providing nationwide UHDTV programming. Mobile carriers want that spectrum for wireless broadband.

In support of providing spectrum for UHDTV, Professor Lee Sang Woon of South Seoul University said, “UHD broadcasting should be universal, all viewers have the right to enjoy it,” adding that providing the public with free UHD broadcasting will let them opt out of expensive cable subscription rates and lessen the digital divide between the rich and poor.

Professor Hong In-Ki of Kyung Hee University pointed out that “Only 6.8 percent of households in Korea currently regularly watch terrestrial broadcasting content and of those people, the number of households that have UHDTV-capable televisions are minimal. The need for better telecommunication services is more universal and individualized, with more than 57 million subscribers in the country.”

Sa Youn Hwang writes, “Although the public hearing ended with officials stating that they would take more time to review the arguments discussed, an overwhelming majority of politicians present at the hearing sided with supporting television stations.”

Doug Lung is one of America's foremost authorities on broadcast RF technology. He has been with NBC since 1985 and is currently vice president of broadcast technology for NBC/Telemundo stations.