A Radio Frequency (RF) Jammer is a device used to disrupt or prevent communication via a broadcasted RF signal. Cell phone jammers work by creating a “dead zone” in the immediate vicinity of the device, which temporarily blocks the signals that make cell phone transmission possible. Most commercially marketed cell phone jammers are small enough to fit in the palm of a hand or in a pocket. The tradeoff is that their range is limited to an average 50 to 80 feet. Larger and more powerful cell phone jammers have a range that can be measured in miles. Read more to know how is jamming done and components used to make a jammer.
Stretching for thousands of miles beneath oceans, optical fibers now connect every continent except for Antarctica. With less data loss and higher bandwidth, optical-fiber technology allows information to zip around the world, bringing pictures, video, and other data from every corner of the globe to your computer in a split second. But although optical fibers are increasingly replacing copper wires, carrying information via photons instead of electrons, today’s computer technology still relies on electronic chips.
Pico projectors are an easy way to increase the screen real estate of your mobile phone, but what if you’d rather not carry one around in your pocket or bulk up your phone’s slim profile with a slip on solution? Well, a team of intrepid researchers may have come up with an elegant solution to your problem that can work with any smartphone and external display: VIRTUAL PROJECTION.
Near Field Communication or NFC is a short-range high frequency wireless communication technology which enables the exchange of data between devices over about a 10 centimeter (around 4 inches) distance. The technology is a simple extension of the ISO/IEC 14443 proximity-card standard (proximity card, RFID) that combines the interface of a smartcard and a reader into a single device. An NFC device can communicate with both existing ISO/IEC 14443 smartcards and readers, as well as with other NFC devices, and is thereby compatible with existing contactless infrastructure already in use for public transportation and payment. NFC is primarily aimed at usage in mobile phones.
As the technology becomes more sophisticated, the need for facile wireless communication has led the human brain to renovate the orthodoxy bottlenecked conventions being used. Computing will inevitably be indispensable and ubiquitous – a scenario that has no place for wires. Bluetooth provides several irksome issues that have plagued implementation of wireless technology handling both data and voice transmissions.
In recent years there has been rapid development in the wireless sector due to demand for wire free connectivity. Most of the development was focused on high data rate applications like file transfer etc with new standards like Bluetooth emerging.
During this time applications that required lower data rates but had some other special requirements were neglected in the sense that no open standard was available.
Either these applications we abandoned in the wireless arena or implemented using proprietary standards hurting the interoperability of the system.
ZigBee is a wireless standard that caters to this particular sector. Potential applications of ZigBee include Home Automation, Wireless Sensor Networks, Patient monitors etc. The key features of these applications and hence aims of ZigBee are
Low Cost
Low Power for increased battery life
Low Range
Low Complexity
Low Data Rates
Co-Existence with other long range Wireless Networks
The ZigBee standard is maintained by ZigBee Alliance is a spin off of the HomeRF group, an unsuccessful home automation related consortium.
It is built upon the IEEE 802.15.4 protocol which is intended for LR-WPAN (Low Rate – Wireless Personal Area Network).
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