Last week the local two-way radio vender in my area, General Communications, had an open house for customers to see their new facility and the radios they sell. Two-way radios were a hobby for me in the late 80s and 90s when I was in high schoo...
If you've ever listened to a weak FM radio station in an urban area, you have heard fading due to interference between reflections from buildings. Fades that cause the signal to drop 10-20dB are common in an urban environment, but they're only...
In an article in the latest issue of IEEE Technology and Society Magazine, researchers propose using RFID to help healthcare workers access medical records. In many developing countries 75% of the population works on rural farms. It is di...
We’ve heard of bags that charge your gadgets — the Powerbag Instant Messenger comes to mind — but none targeted directly at women. That’s where the Everpurse comes in. It’s a Kickstarter project started by married couple Dan and Liz Salcedo. Essentia...
“Charge your smart phone or any other device that supports Qi on top of your night stand. It only took about 1 hour and 45 minutes to build using some tools. You could use almost any type of night stand but this one is from IKEA and therefore sold wo...
What is the similarity between the Toyota Avalon, Jeep Cherokee, Toyota Prius, and the Ssangyong Chairman?The Jeep Cherokee will offer a factory installed Qi wireless charging pad later this year. The optional feature -- located in the center c...
Monster Watts WiQiQi puts wireless charging in Samsung Galaxy phones without new casesSamsung already has wireless charging options for phones like the Galaxy S4, but they require a separate cover that adds a slight amount of bulk. For Monster Watts,...
Here we’re having a look at a set of new Nokia devices, one of the most instantly appealing being the universal NFC Wireless Car Charger. This device is made to work with the Lumia lineup of Nokia devices first and foremost, of course, working ...
I have recently become interested in how we will keep up with the growing demand for wirelss data. Researchers at the University of Southern California are looking into algorithms for caching frequently-used data so a mobile can access it witho...
This is about impedance matching an antenna. The better the cable calibration (nulling), the easier it is. See Part 1 for information on connecting to an antenna and calibrating the VNA. MatchingA typical matching network is a pi con...
If you are getting started with antenna matching, most of the information in books and on the Internet is either highly theoretical or overly simplified. This post will describe a practical procedure of matching an on-board antenna. What Is an O...
The past two weeks this blog has focused on how data and power add up in mobile data networks. This is true for large sensor networks as well. Sensor networks used in oil and gas exploration require geophone sensors to be distributed in d...
For the past ten years, there has been much research into low-power radios for wireless sensor networks. Recently there has been a surge in interest in saving power in mobile data networks. The recent interest in low-power mobile da...
Two weeks ago I wrote about how the heterogeneous network model is replacing the cellular model of mobile phones coverage areas. After writing that article, I visited some friends living outside DC. They told me how their house has very po...
In communications class in the 90s, I was taught this standard hexagonal model for cellular telephone systems. For those not familiar with it, it’s a way to model frequency reuse. No one imagines that radio signals from a give...
Thinking about smoke signals and the first transatlantic cable last week got me thinking about the electrical engineering behind early long-distance wired communication. John Steele Gordon’s A Thread Across the Ocean gives a nice account ...
White smoke from the Sistine Chapel yesterday signaled church leaders had selected a new pope. People hear this and say things like “Smoke signals? Really? Is this some relic from the Council of Nicaea (325 CE) or something?” ...
This past summer I tested a RF remote control based on the PT2262 remote control transmitter. The PT2262 serially encodes a value presented on input pins. This serial output can be used to on-off key an IR or RF transmitter. This al...
McDonald's testing Qi in EuropeRestaurants will install Qi wireless chargers in some of its European restaurants McDonald's is testing wireless charging in partnership with Powerkiss, a Finnish company specialized in the desi...
People prefer Wireless Power The results of the "2012 Engadget Awards, Readers' Choice" are in. 280.000 people voted online for their favorite products in categories such as laptops, digital cameras, and smartphones:58% of the vote...
A link budget is the arithmetic to keep track of all the gains and losses of power between a transmitter and a receiver. A typical transmitter may output 1W. The power travels through the transmission line, to the the antenna, and is radi...
