RF Shorts – Oct. 27, 2011
October 27, 2011
More on Cellphones and Brain Tumors
I noticed several stories on the possible connection between use of cell phones and brain cancer over the past week. KnowAboutHealth.com says Cell phone users not to worry, no brain tumors caused – recent study Christine Stomes writes, "The only known biological effect of radio frequency energy is heating. The ability of microwave ovens to heat food is one example of this effect of radiofrequency energy. Radiofrequency exposure from cell phone use does cause heating; however, it is not sufficient to increase body temperature significantly." She points to a study by researchers at the Institute of Cancer Epidemiology at the Danish Cancer Society in Denmark that found, "There was no indication of dose-response relation either by years since first subscription for a mobile phone or by anatomical location of the tumor – that is, in regions of the brain closest to where the handset is usually held to the head. In this update of a large nationwide cohort study of mobile phone use, there were no increased risks of tumours of the central nervous system, providing little evidence for a causal association." This article includes graphs showing the spectrum and highlighting the difference between ionizing radiation and non-ionizing radiation.
ITWorld Canada covered the same Danish research in an article by Eric Mack, Cellphones don't increase cancer risk: Study. Mack notes, "The authors of the study concede that their findings cannot be considered definitive and that a 'small to moderate increase in risk for subgroups of heavy users or after even longer induction periods than 10-15 years cannot be ruled out without larger studies.
Bryan Walsh raises more questions in his article Why the Latest Study on Cell Phone Use and Brain Cancer Won't Be the Last Word. As he notes in his opening statement, "Proving a negative in science is really, really hard — and that may well be the task that researchers trying to evaluate the potentially carcinogenic effects of cell phone use may have before them."
Time Warner Rejects Antenna Ad
Mohu found that Time Warner Cable doesn't like advertisements that could cost it subscribers. Mohu makes the Leaf HDTV antenna and, as Todd Spangler reports in Multichannel News, the MSO Declined to Air Spot That Says TV Viewers 'Don't Need Expensive Cable Service'. You can view the banned ad here.
Channel Master and Cord-Cutting
Communications Technology writer Linda Hardesty writes Cord-Cutting a Double-Edged Sword for Channel Master. Channel Master makes TV antennas used by over-the-air TV viewers and recently introduced a DVR with a dual tuner for both ATSC TV over-the-air and clear QAM cable. Hardesty notes this puts Channel Master in a delicate position, "On the one hand, it wants to sell its new solution to people who don't subscribe to a cable or telco video service. On the other hand, about four years ago, Channel Master was bought by PCT International, a company well-known for making coaxial connectors used by cable service providers."
Channel Master is partnering with Walmart to incorporate its Vudu app store and movie service with the DVR. Hardesty quotes Channel Master VP of product management and marketing Joe Bingochea, "Channel Master has been able to capitalize on all this talk about cord cutting. Now it's a hot topic. A lot of consumers call us because they're able to cancel their video subscription." He adds, "We don't want to support cord cutting per se. We do make the cords."
More on the LightSquared "Fix" for GPS
GPSWorld.com has an excellent article covering LightSquared: The So-Called "Fix". Eric Gakstatter notes that "This is a spectrum issue that isn't going away even if LightSquared isn't allowed to proceed, so it's in the best interest of the GPS industry to work on a solution no matter what the FCC's decision is." He adds, "There's no way the FCC is going to announce a decision by the end of the year. Mark my words. There's not enough time to confirm a fix, how it might be implemented across multiple manufacturer's receivers, and what the impact is. Believe me, there are many more hearings and information requests that are going to take place before any decisions are made by the FCC."
The Wireless Innovation Forum Conference
While broadcasting is not one of the topics being covered, readers interested in the latest developments in wireless communications may want to check out the 2011 Wireless Innovation Forum Conference on Communications Technologies and Software Defined Radio Nov. 29-Dec. 2 in Washington D.C. Some of the tutorials include RF, ADC, & IF Design Techniques and Next Generation White Nail Architecture for Future Cognitive Radio Transmitter and Receiver Systems. Visit www.wirelessinnovation.org for more information.