Introducing Andrew Walla

This is a guest blog article from Andrew Walla who is working with us and an expert in Radio Frequency Engineering (RF), particularly focusing on small form factor Antennas. So the emphasis is on compact antennas which fits in with our recent emphasis on the Internet of Things (IoT).

Andrew Walla

Andrew Walla

A couple of other caveats. Notable omissions include the pioneering works of Faraday, Orsted and Gauss. For those wanting to dig deeper, the first wireless transmission was by Loomis in 1866, long before Hertz‘ formal experiments were published. The history of wireless television, the Internet and more complex antenna arrangements such as phased arrays has largely ignored in order to keep this brief. And like Analog Electronics , RF and Antennas are a specialised area that is not easy to understand.

And for those who would like to be able to visualize what the final paragraph below means, this animated GIF might help.

Dipole transmitting antenna

Dipole antenna transmitting

The History of Antennas

In his seminal 1864 paper [1], James Clerk Maxwell presented a set of twenty equations (condensed into a set of four vector equations by Oliver Heaviside in 1888 [2]). In this work, Maxwell predicted the existence of electromagnetic waves; a phenomenon which would later be experimentally verified by Heinrich Hertz in a series of papers published in the late 1880s [3].

Guglielmo Marconi was influenced by such findings and worked to extended the field of research; he successfully demonstrated the ability of electromagnetic waves to transmit information over large distances in 1895 and in 1901 he was the first to wirelessly transmit information across the Atlantic Ocean [4]. While Marconi’s research focussed on transmitting information in the form of Morse code, Reginald Fressenden took the challenge upon himself to utilise this technology to transmit the human voice, a challenge which he successfully conquered in 1900 [5]. In 1920, the world’s first commercial radio station began operation (although the title of ‘first commercial radio station’ is contested by many scholars on the basis of differing criteria being used to define the title). This was followed by a rapid spread in radio broadcasting throughout the world in the 1920’s and 1930’s [6, 7].

In the century to follow came television, paging, mobile telephones and wireless internet. The number of wirelessly communicating devices deployed in the world now exceeds the world population [8]. More than one billion such devices are being produced each year and the rate of production is growing [9]. All these devises have an essential element in common that enables their functionality, the antenna.

An antenna is a device to transform a guided wave (a signal inside the circuitry of an electronic device) into a radiated wave (electromagnetic radiation propagating through space). From Maxwell’s equations, we know that an alternating current will emit radiation. We also know that an electromagnetic field will induce a current in a wire. The purpose of an antenna is to act as a transducer between the wireless device and surrounding space, ensuring that the transformation between electromagnetic waves and circuit currents occurs with the desired level of efficiency [10, 11].

References below will assist with further research of this topic.
[1] J. C. Maxwell, “A Dynamical Theory of the Electromagnetic Field,” Philosophical transactions of the Royal Society of London, vol. 155, pp. 459-512, 1865.
[2] O. Heaviside, “The electro-magnet effects of a moving charge,” The Electrician, vol. 22, pp. 147-148, 1888.
[3] H. Hertz, Electric Waves, London: Macmillan, 1893.
[4] G. C. Corazza, “Marconi’s history,” Proceedings of the IEEE, vol. 86, no. 7, pp. 1307-1311, 1998.
[5] J. S. Belros, “Reginald Aubrey Fessenden and the birth of wireless telephony,” IEEE Antennas and Propagation Magazine, vol. 44, no. 2, pp. 38-47, 2002.
[6] W. J. Severin, “Commercial vs. non-commercial radio dring broadcasting’s early years,” Journal of Broadcasting & Electronic Media, vol. 22, no. 4, pp. 491-504, 1978.
[7] J. E. Baudino and J. M. Kittross, “Broadcasting’s oldest stations: An examination of four claimants,” Journal of Broadcasting & Electronic Media, vol. 21, no. 1, pp. 61-83, 1977.
[8] GSMEA Intelligence, “GMEI 2017 Global Mobile Engagement Index,” GMSA Intelligence, London, 2017.
[9] T. Nguyen, J. T. McDonald and W. B. Glisson, “Exploitation and Detection of a Malicious Mobile Application,” Proceedings of the 50th Hawaii International Conference on System Sciences, 2017.
[10] A. K. Skrivervik, J. -F. Zürcher, O. Staub and J. R. Mosig, “PCS Antenna Design: The Challenge of Miniaturization,” IEEE Antennas and Propagation Magazine, vol. 43, no. 4, pp. 12-27, 2001.
[11] S. M. Wentworth, Applied electromagnetics: early transmission lines approach, John Wiley, 2007.

Andrew Walla, RF Engineer, Successful Endeavours

Successful Endeavours specialise in Electronics Design and Embedded Software Development, focusing on products that are intended to be Made In Australia. Ray Keefe has developed market leading electronics products in Australia for more than 30 years. This post is Copyright © 2017 Successful Endeavours Pty Ltd.