A Cursory Historical Overview on the Evolution of Wireless Communications
Magdalena Salazar-Palma*, Senior Member, IEEE, and Tapan K. Sarkar**, Fellow, IEEE
*Signal Theory and Communications Department, Universidad Carlos III de Madrid, Spain, e-mail: [email protected]
** Electrical Engineering and Computer Science Department, Syracuse University, USA, e-mail: [email protected]
Abstract — This presentation offers a historical overview on
the evolution of field theory for wireless communications. Index Terms — History, wireless, radio, communications.
I. INTRODUCTION
Electricity and magnetism are as old as human civilization. The Chinese navigated the Indian Ocean using magnetite floating on mercury, around 1000 BC. The Baghdad battery (Fig. 1) was radio carbon dated to 250 BC, long before the Italian physicist Alessandro Giuseppe Antonio Anastasio Count Volta (Fig. 1) constructed his pile in 1799. During the seventeen and the eighteen century a number of experiments and inventions were carried out by scientists all over the world. They paved the way for the crucial discoveries of the nineteenth and twentieth century that made possible wireless (or radio) communications. Some of those discoveries are highlighted in this presentation.
English chemist and physicist Sir Henry Cavendish (Fig. 2) discovered the inverse square law and even experimentally verified it 10 years before French physicist Charles-Augustin de Coulomb (Fig. 2) did and even anticipated the law derived by German physicist and mathematician Georg Simon Ohm (Fig. 3) which was compiled and published 100 years later. German scientist Munk A. Rosenshold discovered the semiconductor rectifying action over alternating current in 1835. According to USA Congress (HR269), the first demonstration of telephone was made by Antonio Santi Giuseppe Meucci (Fig. 3), at Havana, Cuba, in 1841 [1]. He
also demonstrated that inductive loading of the circuit improved its performance. In 1855 French engineer Jean-Mothée Gaugain studied the rectifying action between two metal balls in an evacuated chamber, producing the first Electric Valve.
In 1861, Scottish physicist and mathematician, James Clerk Maxwell (Fig. 4), the father of electrical engineering, wrote to British scientist Michael Faraday (Fig. 4), indicating that he has vindicated his theory on action at a distance and have reached the conclusion that light was electromagnetic in nature using dimensional analysis. Maxwell could still be called the father of electrical engineering and the greatest scientist of the last century even if he would have not done any work on electromagnetic theory! He provided a general methodology
Figure 2. Left: Henry Cavendish. Right: Charles-Augustin de Coulomb.
Figure 3. Left: Georg Simon Ohm. Right: Antonio Meucci.
Figure 4. Left: James Maxwell. Right: Michael Far for the solution of Kirchoff’s laws as determinants, showed how a circuit ccapacitance and inductance would respond whgenerators containing alternating currentfrequencies, thus developing the phenomenresonance. He took the first color photogrseparate pictures using red, green and blue, bthe same principles that modern television although his name is rarely mentioned [2]. Hpaper on control theory and introduced the firin to physics, in addition to the concept ensemble averaging which is routinely processing and information theory. He compconcept of curl, gradient, divergence in his twoon Electromagnetism which interestingly diimportance to the displacement current. He wrbut not the boundary conditions to solve themwrong gauge, in addition. The modifications owere first accomplished by German physicist Hertz (Fig. 5) around 1884, who wrote the four today into twelve equations in a scalar form. time period, they were cast independently intoresulting into the four equations that we use tphysicist, mathematician, and electrical Heaviside (Fig. 5), who did not have aeducation! This is why Albert Einstein used toequations as Maxwell-Heaviside-Hertz equation
Figure 5. Left: Hertz. Right: Heaviside.
raday.
a ratio of two containing both hen connected to ts of different non of electrical raph using three based exactly on
operates today, He wrote the first rst statistical law of entropy and used in signal
piled in 1864, his o volume Treatise id not give any rote 20 equations,
m, and he used the of those equations
Heinrich Rudolf r equations we use
During the same o the vector form, today, by English engineer Oliver
a formal college o refer to the four ns.
Interestingly, the same year in treatise, American dentist Mahlon earliest description of a wireless generated the world’s first patent o1882, a Kentucky melon farmer Na6), transmitted audio signals withou
Figure 6. Left: Mahlon Loomis. Right: N
In 1895 Russian inventor Alex(Fig. 7) demonstrated his Thundeaerial, a coherer, and an electromelectrical engineer Guglielmo Maand received a coded message at a his home at Bologna, Italy. The sam
Figure 7. Left: Alexander Popoff. Right
Sir Jagadis Chunder Bose (Fig. 8wireless signals of 6 mm wavelengvariety of devices and techniques: wcut-off grating, dielectric lens, micprism directional coupler, podielectrometer, and so on. His wdevice to a horn antenna intriguedStrutt, 3rd Baron Rayleigh (Fig. 8), sto visit him and on his way back gpropagation through waveguides.
which Maxwell wrote his Loomis (Fig. 6) wrote the
transmission system and on Wireless Telegraphy. In athan B. Stubblefield (Fig. ut wires.
Nathan Stubblefield.
xander Stepanovich Popoff rstorm Recorder using an
magnetic relay and Italian arconi (Fig. 7) transmitted distance of 1.75 miles near me year, Indian physicist
t: Giuglielmo Marconi.
8) generated and detected th. He produced a fantastic wave-guides, horn antenna, crowave reflectors, double-larimeter, interferometer, waveguide connecting his his mentor, John William so much that he made a trip generated the first paper on
Figure 8. Left: Sir Jagadis Chunder Bose. Right: Lord Rayleigh.
Croatian-American electrical engineer Nicola Tesla (Fig. 9) demonstrated a radio controlled boat in Madison Square Gardens in 1896. Brazilian Catholic priest and inventor Father Roberto Landell de Moura (Fig. 9) was the first to accomplish the transmission of the human voice by a wireless machine that is, by irradiating an electromagnetic wave, modulated by an audio signal. He conducted his first public experiment on June 3, 1900. The same year Tesla obtained patents USP 645,576 and 649,621 on System of Transmission of Electrical Energy, submitted in 1897, which United States of America Supreme Court recognized to be the first patents on Radio. Marconi submitted his first US patent also in 1900. He continued to submit patents on Radio. They were all turned down. The same year Canadian-American physicist and inventor Reginald Aubrey Fessenden (Fig. 10) did the first speech transmission (over 25 miles) using a spark transmitter.
Figure 9. Left: Nicola Tesla. Right: Father de Moura.
By the early 1900s, Marconi has succeeded in transmitting wireless signals over large distances and thus he proved the contemporary scientific community to be wrong, as nobody thought that wireless transmission over such long distances was possible. He succeeded for two reasons, first going to lower frequency, and second by connecting one end of his tuning circuit to the earth and the other end to an aerial. In 1904 the United States Patent Office reversed itself and gave the Radio patent to Marconi. However, in 1943, two months
after Tesla’s death, the US Supreme Court upheld Tesla’s patent 645,576 for invention of Radio. The court had selfish reasons for doing so. Marconi Company was suing the American government for using its patents in World War I. The court simply avoided the action by resorting priority to Tesla’s patent over Marconi. In 1905 Slovak Catholic priest and inventor Jozef Murgas (Fig. 10) achieved radio transmission of information between Wilkes-Barre and Scranton, Pennsylvania (a distance of 20 miles or 30 km). Murgas invented the so called tone system which diminished the time needed to deliver a signal and thus considerably improved the system.
Figure 10. Left: Reginald Fessenden. Right: Jozef Murgas.
III. CONCLUSION Some of the crucial events up to 1905 have been
highlighted. The aim of this presentation has been also to illustrate that simultaneous developments were going on all over the world and that each invention provided a solution to a portion of the puzzle.
It is also quite interesting to observe that many of the key developments in wireless were made by researchers who had little formal education. Also Maxwell, who was a mathematician by training, wrote that he did not want to employ any mathematical principles until he went through all of Faraday’s experiments in order to understand first the physical phenomena involved. Thus, one other conclusion of this presentation could be that in our teaching we should first provide the context and highlight the physical phenomena before going through all the mathematical details. Perhaps it is time for a change!
REFERENCES [1] T. K. Sarkar, R. J. Mailloux, A. A. Oliner, M. Salazar-Palma,
and D. L. Sengupta, History of Wireless, John Wiley & Sons – IEEE Press, Hoboken, NJ, USA, 2006.
[2] T. K. Sarkar, M. Salazar-Palma, D. L. Sengupta, “Who Was James Clerk Maxwell and What Was/Is His Electromagnetic Theory”, Feature article, IEEE AP Society website, http://www.ieeeaps.org/ .
