A review of RF-related news during the past week.
5G 60 GHz Broadband Technology Continues to Attract Attention
Lately, I've been reporting on companies and researchers working on the next generation wireless broadband technology, 5G. It won't work in UHF TV spectrum and is unlikely to work in most of the broadcast auxiliary service microwave spectrum.
Most researchers are focusing on spectrum at 60 GHz. Considering the difficulties in operating at such a high frequency, 5G seemed a long way off.
Or perhaps not.
GigaOm.com writer Kevin Fitchard reported last week Google wades into the murky waters of 5G with Alpental buy
. Fitchard writes, "Buying a company that specializes in 5G technologies doesn’t mean Google wants to build a 5G mobile network. Alpental is working on 60 GHz wireless networks, which could be used to augment Google’s many broadband projects."
Fitchard had this to say about 5G in general: "5G hasn’t even been defined by the mobile industry yet, but the companies and researchers that are pursuing those standards agree that 5G isn’t going to be a single network technology. Rather, it’s going to be a mishmash of different radios, new bands of spectrum and even the melding of different kinds of networks using licensed and unlicensed airwaves to reach users. Basically, the industry is using every tool it can find to cram more capacity into future networks."
Senate Bill Would Reallocate 5.9 GHz Spectrum to Wi-Fi
According to Grant Gross' article Senate bill aims to expand Wi-Fi spectrum
in Computer World, amateur radio operators, some satellite services, and intelligent vehicle communications system could end up sharing the 5850-5925 MHz band with Wi-Fi.
He writes: "The Wi-Fi Innovation Act attempts to balance the needs of incumbent users of the 5850-5925 MHz band, including growing use of so called intelligent transportation systems, focused on vehicle safety and traffic information, with a major need for more Wi-Fi spectrum, the senators said in a statement. The bill encourages users of the band to share spectrum if possible, they said."
Gross notes: "With only weeks before the 2014 campaign season kicks into high gear, the bill is unlikely to pass during this session of Congress. The sponsors could reintroduce the bill during the new session of Congress beginning next January."
Sweden's 'Alexanderson Day' Activities Include 17.2 KHz Transmission
VLF (very low frequency) RF enthusiasts will have another opportunity to test their equipment this weekend. ARRL reports SAQ
"Alexanderson Day" Transmissions Set for June 29 and July 2
. "The annual "Alexanderson Day" transmission from the World Heritage Grimeton site in Sweden, using the vintage Alexanderson alternator on 17.2 kHz, will take place Sunday, June 29 at 0900 UTC (SAQ will start tuning at about 0830 UTC) and again at 1200 UTC (SAQ will start tuning at about 1130 UTC). An SAQ transmission will take place on July 2 at 1430 UTC (SAQ will start tuning at about 1400 UTC, to mark 10 years since SAQ was designated as a World Heritage site."
Three U.S. listeners reported they were able to receive the last transmissions sent in January. Since 17.2 kHz is within the range of PC sound cards, it should be possible to use a computer's sound card to receive the transmissions, with the appropriate antenna, of course.
The ARRL release described the SAQ transmitter:
"Dating from the 1920s, the Alexanderson alternator—essentially an ac alternator run at extremely high speed—can put out 200 kW, but typically is operated at less than one-half that power level. Once providing reliable transatlantic communication, it is now a museum piece and only put on the air on special occasions. The transmitter was developed by Swedish engineer and radio pioneer Ernst Alexanderson, who was employed at General Electric in Schenectady, N.Y., and was chief engineer at the Radio Corporation of America. Six 400+ foot towers with 150 foot crossarms support a multi-wire antenna for SAQ. The actual signal radiates from a vertical wire, one from each tower."
Comments and RF related news items are welcome.
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