Charging cables, while a necessity, are something we’d like to never have to use again. That means batteries too. Battery technology, despite the increasing need in the auto industry, is only slowly advancing, but the results show potential. Researchers have been investing resources into annihilating cables; not long ago researchers from the University of Washington presented a system they named Power over Wi-Fi (PoWiFi). More recently, scientists from MIT and the Technical University of Madrid are looking into a new way of converting energy from Wi-Fi signals into electricity that could power electronics. Their latest study involves a new kind of rectenna: a device that converts alternative current electromagnetic waves into direct current (DC) electricity. The rectenna uses a flexible radio-frequency antenna which captures electromagnetic waves, including those carrying Wi-Fi, as alternative current (AC) waveforms. This antenna is then connected to a novel device called rectifier, for which the researchers used a two-dimensional semiconductor just three atoms thick (called molybdenum disulfide—MoS2), one of the thinnest semiconductors in the world. The AC signal travels into the semiconductor, which converts it into a DC voltage that can be used to power electronic circuits or recharge batteries. In short, this battery-free device passively captures and transforms ubiquitous Wi-Fi signals into useful DC power. Furthermore, the device is flexible and can be set up to cover very large areas. “What if we could develop electronic systems that we wrap around a bridge or cover an entire highway, or the walls of our office and bring electronic intelligence to everything around us? How do you provide energy for those electronics?” asked Tomás Palacios, a professor in the Department of Electrical Engineering and Computer Science & director of the MIT/MTL Center for Graphene Devices and 2D Systems in the Microsystems...

Wi-Fi revolutionized the way we connect to the internet, but it’s not without flaws. Researchers have been busy looking for new kinds of technologies that could offer more reliable alternatives. One is called Li-Fi (Light Fidelity). Back in 2011, a group of scientists led by Professor Harald Haas from Edinburgh University in Scotland introduced the idea of “Wireless data from every light” during a TED Talk. The general term is visible light communication (VLC) and is similar to the Morse code; it dates back to the 1880s and includes any use of the visible light portion of the electromagnetic spectrum to transmit information. Li-Fi is a type of visible light communication system that runs completely on wireless communications by means of travelling at very fast speeds. Confusing or not, this emerging technology is projected to expand its market worth to $80 billion by 2021. So let me explain. Wi-Fi and Li-Fi are pretty similar—they both provide the same means of transmitting data electromagnetically; yet, Wi-Fi utilizes the usage of radio waves, while Li-Fi runs solely off of the visible light. Even though invisible to the naked eye, waves are transmitted from our devices, carrying bits of data that allow us to browse the internet. There is a constant communication with towers called cellular radio masts. According to the founder of Li-Fi, Harald Haas, there are approximately 1.4 million cellular radio masts worldwide. Li-Fi replaces this bulky infrastructure with a solution relying on LED lights that send data over visible light via pulses undetectable by the human eye. Moreover, on the electromagnetic spectrum the spectrum of visible light is 10,000 times as big as that of radio-waves, said Haas. Unlike Wi-Fi signals, which can penetrate walls, Li-Fi is based on light and can’t, so theoretically,...

Ever wonder what the future looks like for New York City’s payphones? Well,  you won’t be seeing them for too long as they disappear like the extinct species they’ve become. But a new public utility kiosk is coming along to take their place. LinkNYC, a consortium of experts in technology, media, user experience and connectivity that includes Intersection, Qualcomm, and CIVIQ Smartscapes, has plans to replace them with a high-tech sibling. The launch has already begun with a beta phase rolling out a fiber optic network of kiosks equipped with different types of free services such as high speed internet, web browsing, cell phone charging and calls to within the U.S. Additional apps, features and services will be rolled out on an ongoing basis over the next few years. “It’s going to be the largest and fastest public Wi-Fi network in the world,” Collin Odonell, managing member of CityBridge, said in a prepared statement. “It’s really the first of this kind of network and it’s going to transform the streets and people’s way to access information.” Privacy and security is the main concern, especially when the subject is some public Wi-Fi network. LinkNYC claims it offers two types of networks: a public Wi-Fi one and a private encrypted one. The private, fully equipped network is accessible only by devices that support Hotspot 2.0 (currently, LinkNYC only supports Apple gear). On its public network, LinkNYC will be able to track the user’s MAC address (which won’t be tracked either, claims LinkNYC). In addition, users will have the option to clear their sessions once they’ve done using the kiosk. Please keep in mind though that it’s still very risky to log in to bank accounts over public networks and that even though the user information won’t...