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Revolutionizing Healthcare by Coupling Unmanned Aerial Vehicles (UAVs) to Internet of Medical Things (IoMT)
Published in Chinmay Chakraborty, Digital Health Transformation with Blockchain and Artificial Intelligence, 2022
Faris A. Almalki, Soufiene Ben Othman, Hedi Sakli, Marios Angelides
Guglielmo Marconi’s development in the late nineteenth century of the wireless telegraph system marked the beginning of the wireless age. He was preceded by Jagdish Chandra Bose by sending a signal to remotely strike a bell and detonate a stun on millimetre frequency in 1895. This was followed by the completion of the first radio transmission in 1906, establishing the first true wireless industry (radio equipment) in the 1920s. The Second World War played an important role in the development of wireless technologies to meet the military needs in the field of radio communication systems, radar, and encryption [10]. The first civilian wireless telephone system (first generation) appeared in the seventies of the twentieth century in the United States of America. The 1990s saw an acceleration in the wireless sector, with the first commercial GSM (global system for mobile communications) networks appearing in Scandinavia in 1991. The paging service invaded Europe in the mid-nineties of the twentieth century, and at the end of the twentieth century, medium-range wireless data networks emerged in the form of wireless local networks and Bluetooth system. The beginning of the twenty-first century is the beginning of the era of the wireless Internet [11].
Networking: Concepts and Technology
Published in P. S. Neelakanta, ATM Telecommunications, 2018
An extension of terrestrial telegraphy is known as radio or wireless telegraphy facilitated via a wireless transmission network. Here, the on-off keying (corresponding to dots and dashes) allows an electromagnetic wave at a radio frequency transmitted or cut-off. The on-off state of the carrier is detected and decoded at the receiving end. As necessary, the radio telegraphic message can be relayed from one station to another station via a wireless network.
The Electromagnetic Phenomena as Incitants
Published in William J. Rea, Kalpana D. Patel, Air Pollution and the Electromagnetic Phenomena as Incitants, 2018
William J. Rea, Kalpana D. Patel
In 1800, Herschel8 discovered infrared light, and the next year, Ritter9 described invisible light rays that induced chemical variations. In 1845, Faraday10 linked EM to the polarization of light traveling through a transparent material responding to an EM field. In the 1860s, Maxwell11 developed a partial differential equation for the EM field. This observation led to the inference that light itself was an EM wave. His equation predicted an infinite number of frequencies of EM waves, all traveling at the speed of light. Hertz12 built an apparatus to generate and detect radio waves. He also produced and measured the properties of the microwave. The knowledge of these new types of waves paved the way for the wireless telegraph and the radio. Rontgen13 noticed x-rays when experimenting with high-voltage radiation in a evacuated tube. Villard14 studied the radioactive omission of radiation-identified x and b particles with the power being greater than either (gamma rays). Audrade15 measured the length of gamma rays and found they were shorter with higher frequencies than x-rays. Of course, today, we have a myriad of aberrative and technical changes in this field.
Rutherford and the Cavendish Laboratory
Published in Journal of the Royal Society of New Zealand, 2021
At the end of 1893 while still at Canterbury College, Rutherford began his physics research career with an investigation into the magnetisation of iron by high frequency discharges. He continued work in this area when he arrived in Cambridge and developed a magnetic detector for electromagnetic waves (Figure 2). In December 1895, he demonstrated the operation of the detector at a distance of 200 yards from a Hertzian spark transmitter. The first outdoor use of the detector occurred on 22 February 1896 when he set up a spark transmitter on Jesus Green and detected the radiated pulses at a distance of 350 yards in a house on Park Parade. On the following day, a successful transmission over a distance of nearly three quarters of a mile was achieved. Rutherford held the world record for the reception distance at the time. In the same year, however, Marconi came to England and developed a system for the transmission of Morse code signals by means of electromagnetic waves, the beginning of wireless telegraphy.