Friday, December 19, 2008

Look Mom, No Batteries - Peregrine & K-State Working Together on Energy Harvesting Radios

Kansas State University engineers are helping Peregrine implement its idea of an energy-harvesting radio. This concept could be used to implement bridge structural integrity monitoring with wireless sensors since changing the batteries on hundreds of sensors on each bridge is not practical. Kansas State is developing the energy harvesting radios for Peregrine to be used in these types of applications.

Peregrine's UltraCMOS process leads itself well to very low power devices and K-State engineers are looking at the design challenges of a radio system. Although the prototype captures and stores light energy with solar cells, these energy-harvesting radios could be powered by a number of different ways, including by electrochemical, mechanical or thermal energy. Some of this research is a spin off of work done for NASA for use on Mars rovers and scouts.

This leads me to another interesting technology that has caused some buzz lately which is using microwaves to power devices. WiTricity promises to power devices and lights via inductive coupling like Tesla first demonstrated many years ago. However, no one has ever been able to find a method to implement it for widespread practical use. But MIT has recently developed new technology that might solve this problem and a couple of companies are trying to bring it to market. Here is one such company's videos that are very well done and demonstrate some of its uses. While I don't see this being very good for lighting purposes in the near future, I think the convenience of charging our wireless devices via this method could take off. You just place your cell phone, iPod or other device on the counter in the vicinity of the charging unit and it will always have enough juice to go when you are ready. Let us know what you think of this new approach and if you think it will ever catch on.

Thursday, December 18, 2008

MWJ top ten most viewed technical articles of 2008

Though a tad early, we thought we would get a jump on sharing our top-ten list of web-published articles for 2008. Scanning through statistics in our web site’s back office gives us a pretty good glimpse of which articles were most read by you. Without accounting for when the article was published (articles published earlier in the year have a definite time advantage), the ten most read technical articles were:

1. Now: Phased-array Radars: Past, Astounding Breakthroughs and Future Trends by E. Brookner was very popular the moment it was posted and continued to be well read through-out the year.
2. New Waves: MTT_S Product Showcase by MWJ Staff is always a popular theme, this year was no exception.
3. Phase Noise: Theory versus Practicality. This article was printed more than any other.
4. Measuring S-parameters: The First 50 Years by D. Vye led the pack in articles most often e-mailed to a colleague
5. IMS 2008: A Peachy Return to the East Coast by P. Hindle was the article most read in the month following its posting.
6. An Enabling New 3D Architecture for Microwave Components and Systems by D. Sherrer, this article was accompanied by an executive interview (David Sherrer of Rohm & Haas) which was the most read online executive interview of 2008.
7. Then: Array Radars: A Survey of Their Potential and Their Limitations (May 1962) was the only retrospective article making the top-ten list, but not a bad result for an article that was first published in May 1962.
8. An Historical Perspective on 50 Years of Frequency Sources
9. A 60 GHz Millimeter-wave CMOS RFIC-on-chip Dipole Antenna by H.R. Chuang, S.W. Kuo, C.C. Lin and L.C. Kuo, which was posted online in January 2007
10. High Harmonic-rejection Matching Filters for Quad-band Power Amplifiers written by Rajanish, P. Onno and N. Jain, and published in May 2006

Articles in the ninth and tenth position were from January 2007 and May 2006, respectively, proving that a good technical article can enjoy a long and prosporous life online.

Wednesday, December 17, 2008

A Sparkling New Microwave Idea for the Holidays

In case you did not see this news item, I just thought I had to share it since it is so appropriate for the holidays (Source: Carnegie Institution for Science):

If you are still deciding on what to give the woman (or microwave engineer) who has everything this holiday season, then researchers in Washington may have solved that last minute gift problem – microwaved diamonds. Members of Carnegie Institution’s Geophysical Laboratory have used a chemical vapor deposition (CVD) method to grow synthetic diamonds for their experiments. Unlike other methods, which mimic the high pressures deep within the earth where natural diamonds are formed, the CVD method produces single-crystal diamonds at low pressure. The resulting diamonds, which can be grown very rapidly, have precisely controlled compositions and comparatively few defects.

The Carnegie team then annealed the diamonds at temperatures up to 2,000° C using a microwave plasma at pressures below atmospheric pressure. The crystals, which are originally yellow-brown if produced at very high growth rates, turned on the size of crystals or the number of crystals, because the method is not limited by the chamber size of a high pressure press. The microwave unit is also significantly less expensive than a large high-pressure apparatus.

Unfortunately, those late holiday shoppers will still have to go to the store rather than the lab for that diamond ring because the high-quality, single crystal diamond made possible by the new process has a wide variety of applications in science and technology rather than for jewelry. These include the use of diamond crystals as anvils in high-pressure research and in optical applications that take advantage of diamond’s exceptional transparency. Among the more exotic future applications of the pink diamonds made in this way is quantum computing, which could use the diamonds’ NV centers for storing quantum information.