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Anatech Electronics, a manufacturer of RF and microwave filters, has published its July 2016 newsletter. As always, it includes both company news and some tidbits about relevant industry happenings. This month, Sam Benzacar continues his previous discussion regarding the increasing challenge that interference is to mission-critical systems. He also reports on news about cancers risks that come with extensive cellphone use, LTE-U deployment schedules, E-Band data system advances, and using radar-based sensors to monitor and characterize patient behavior and health status. Anatech's business is to make certain that system and circuit designers have capable filters available to assure successful implementation.
By Sam Benzacar
RF interference is often merely an annoyance that doesn't degrade a receiver's performance enough to make it unusable. However, as I've noted in previous newsletters, this is becoming the exception rather than the norm, and when it affects mission-critical systems the problem needs to be found and fixed--fast.
While the term "mission-critical" is generally associated with systems used by first responders--EMS, paramedics, police, and fire--it extends much further to hospitals and all types of medical facilities, colleges, universities, and local schools, transportation networks, county and municipal services and emergency response teams, and private land-mobile radio systems used in dozens of industries.
Medical facilities, especially hospitals, extensively rely on the electromagnetic spectrum for communications, patient telemetry, and a broad array of surgical applications. In addition to campus security, colleges and universities are adding or upgrading surveillance and emergency broadcast systems that alert students and staff to serious events. Reliable communication is also essential for rail and bus transportation as well as the nation's ports where a complex fabric of activities is performed around the clock. All of these systems or portions of them can be rendered useless by the presence of strong (and sometimes not so strong) interfering signals.
As a manufacturer of RF and microwave filters, Anatech Electronics is getting an increasing number of urgent requests for solutions to problems in these sectors from people who need to make interference rapidly "go away", like…yesterday. While yesterday is impossible short turnaround is not, thanks to our library of more than 5,000 designs that may either be in stock or can be modified quickly, and without NRE.
So if you're faced with an interference problem that has mysteriously appeared and is compromising your mission-critical system, please call us at (973) 772-4242 or send an email to firstname.lastname@example.org. After more than 25 years of solving "unsolvable" interference problems, chances are we've encountered your problem before.
Media Downplays Latest Cellular Cancer Scare
The National Toxicology Program (NTP) just released preliminary results of its cellular radiation study and were so concerned that they skipped the usual, time-consuming approach of peer review and just issued its findings. They team found elevated rates of two types of cancer among exposed rats, which caused the American Cancer Society (ACS) to conclude that the NTP's study was noteworthy and "good science", according to Otis Brawley, ACS' chief medical officer. Consumer Reports called it "groundbreaking" and encouraged people to take simple precautions to limit their exposures.
In the mainstream media, no doubt jaded by the seemingly endless stream of studies that ultimately go nowhere, the response was, as the Washington Post headline stated: "Do Cell Phones Cause Cancer? Don't Believe the Hype." The New York Times discredited the report arguing that if the link was real brain tumor rates would be increasing. But in fact they are in some of the most horrid brain tumors called GBMs. For more information, read the story in Microwave News here.
Maybe End-of-the-Year LTE-U Deployments Aren't a Pipe Dream, After All?
The Wi-Fi Alliance says it is moving according to plan on a co-existence testing standard for LTE-U products, which will be issued in August, and the process is currently in the validation phase. LTE in unlicensed spectrum (LTE-U), originally developed by Qualcomm, makes use of 4G LTE technology in unlicensed 5 GHz spectrum used by Wi-Fi as an alternative to carrier-owned Wi-Fi hotspots. Google and other companies have filed complaints with the FCC about how well LTE-U can co-exist with existing services.
The alliance stated that the test plan will provide "accurate, repeatable results more reliable than the assorted co-existence tests conducted today." After the plan is released, testing will begin immediately by third-party labs. The Wi-Fi Alliance's believes its co-existence testing will be one way the FCC evaluates whether LTE-U devices will be approved. For its part, the FCC wants industry to resolve the fair-sharing issues on its own. Verizon and T-Mobile expect to have their solutions in place by the end of this year.
E-Band Transmission Sets New Record
Researchers at the Fraunhofer Institute for Applied Solid State Physics and the University of Stuttgart in Germany set a new record for wireless transmissions, transferring DVD in less than 10 s over a signal path of 23 miles, a tenfold increase over previous records. The transmission link achieved a data rate of 6 Gb/s using transmitters and receivers operating at 71 to 76 GHz currently used for satellite communications and vehicle radar. The receiver used very-low-noise amplifiers fabricated in indium-gallium-arsenide (InGaAs) to detect the faint signals and the transmitters delivered a surprisingly high 1 W using gallium nitride (GaN) devices. The researchers say a single beam could serve up to 250 Internet connections at 24 Mb/s.
Radar Sensors in Beds Help Seniors
Researchers at the University of Missouri have been working on motion-capture technology to help older adults "age in place" for more than a decade but their latest results show how monitoring walking speed using radar and heart health by utilizing bed sensors can help maintain older adults' health and warn of impeding issues. "In-home sensors have the ability to capture early signs of health changes before older adults recognize problems themselves," said Marjorie Skubic, professor of electrical and computer engineering in the MU College of Engineering and director of MU's Center for Eldercare and Rehabilitation Technology.
"The radar enhances our ability to monitor walking speed and determine if a senior has a fall risk; the bed sensors provide data on heart rate, respiration rate, and overall cardiac activity when a senior is sleeping. Both sensors are non-invasive and don't require seniors to wear monitoring devices." The radar sensors were used to monitor the walking speed of residents in apartments for 2 years, concealed in a box and placed in the living room of each senior resident. The resulting data was then compared to the data captured by the radar.
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About Anatech Electronics
Anatech Electronics, Inc. (AEI) specializes in the design and manufacture of standard and custom RF and microwave filters and other passive components and subsystems employed in commercial, industrial, and aerospace and applications. Products are available from an operating frequency range of 10 kHz to 30 GHz and include cavity, ceramic, crystal, LC, and surface acoustic wave (SAW), as well as power combiners/dividers, duplexers and diplexers, directional couplers, terminations, attenuators, circulators, EMI filters, and lightning arrestors. The company's custom products and capabilities are available at www.anatechelectronics.com.
Anatech Electronics, Inc.
70 Outwater Lane
Garfield, NJ 07026
Posted July 7, 2016