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Understanding phase noise in signal generators

Source:  http://www.testtek.com/en/detail-info.php?id=2151 Signal generators manufacturers set great store by specifying phase noise, such that, regardless of the application, phase noise is frequently taken as a proxy of the equipment's overall performance. However, phase noise performance might have little or no affect in some applications. For example, 'close in' phase noise creates problems when the signal generator is used as a local oscillator, limiting its sensitivity or impairing bit error rate (BER) performance if used as a clock. 'Far out' phase noise, on the other hand, affects wideband communications systems by raising the noise floor and limiting the reception of poor signals. Choosing a signal generator to match phase noise performance to the requirements of the application can be difficult as manufacturers often characterise phase noise performance at different carrier wave frequencies and at different offsets from the carrier signal. ...
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What is Internet of Things (IoT)?

Source:  http://testtek.com/en/detail-info.php?id=2139 The  Internet of Things  ( IoT , sometimes  Internet of Everything ) is the network of physical objects or "things" embedded with electronics, software, sensors and connectivity to enable it to achieve greater value and service by exchanging data with the manufacturer, operator and/or other connected devices based on the infrastructure of International Telecommunication Union's Global Standards Initiative.  Internet of Things connect physically and remotely by individuals, for both public sector and private sector,  in the sense of a computer network grid, of a created electrical device that is in place, with economic benefit and potential usefulness.  Each thing is uniquely identifiable through its embedded computing system but is able to interoperate within the existing  Internet  infrastructure. Experts estimate that the IoT will consist of almost 50 billion obj...
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Looking inside supercapacitors could help to build higher performing parts Researchers from the University of Cambridge, together with French collaborators based in Toulouse, have developed a method that allows the inside of supercapacitors to be viewed at the atomic level. The team says this approach could be used in order to optimise and improve the devices. By using a combination of nuclear magnetic resonance (NMR) spectroscopy and scales sensitive enough to detect changes in mass of a 1µg, the researchers could visualise how ions move around in a supercapacitor. They found that, while charging, different processes are at work in the two identical pieces of carbon 'sponge' which function as the electrodes. Dr John Griffin, a postdoctoral researcher in the Department of Chemistry, said: "[Supercapacitors are] much better at absorbing charge than batteries, but since they have much lower density, they hold far less of that charge. Being able to see wh...
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