Voice communication became possible when Alexander
Graham Bell invented the telephone on March 10, 1876. His
experiments with his assistant Thomas Watson finally proved
successful when the first vocal sentence was transmitted:
“Watson, come here; I want you.” The telephone was demonstrated
to the world at the 1876 Centennial Exposition in
Philadelphia, Pennsylvania, and led to the creation of the Bell
Telephone Company in 1877.
By 1906 American inventor, Lee De Forest, invented a
three-element vacuum tube that revolutionized the entire field
of electronics by allowing amplification of signals, both telegraphy
and voice. The first radio broadcast in the United States
was made in 1906, and within four years the first broadcast
from the Metropolitan Opera House was transmitted.
Wireless voice communications using amplitude modulation
(AM) was a reality. The ensuing years of the 1920s saw
tremendous growth in radio station broadcasting that brought
the possibility of real-time information to the public. Society
changed forever…again. The radio became a necessity for people
to communicate information and ideas over vast distances
without wires.
Of course, wires still had their place because radio was not
always the most reliable medium. The environment, weather,
time of day, and man-made interference could interrupt communications.
Telephone technology advanced steadily, and telegraphy still found a place in data communications in the
form of the telegram.
Radio technology advanced throughout the 1930s with the
notable invention of frequency modulation (FM), which provided
better sound quality and was more resistant to interference
than the older AM broadcasting system. One of the first
applications for FM was police radio; it was ideal for mobile
communications. Commercial FM broadcasting did not develop
until much later in the twentieth century. It should be noted
here that FM technology became the cornerstone of the analog
cellular system launched in 1983.
World War II accelerated the advancement of radio communications
and electronics. Transatlantic cables between Europe
and North America improved but we were still limited to realtime
communications by copper cables or high-frequency (HF)
radio spectrum under 30 megahertz. Data was still limited to
telegraphy or some analog signals representing data. This was
acceptable because demand for data was also low.
However, the post-war period saw an explosion of innovation
with the development of the transistor (December 1947)
and the birth of the computer. In the Moore School of
Engineering, ENIAC, the world’s first electronic, large-scale,
general-purpose computer, was activated at the University of
Pennsylvania in 1946. Unfortunately, the computer preceded
the transistor so ENIAC contained about 18,000 tubes. This
was much to the chagrin of the graduate students who had to
replace the burned out ones—often! Some refer to this as the
Birth of the Information Age, but we like to think of it as the
Re-Birth of the Information Society. Computers provided a tool
for people to process data, lots of data; now we needed a better
way to move that data faster.
The 1950s had many “Ages” to ponder, the Atomic Age, the
Information Age, and if that was not enough, another almost 100
years after the first transoceanic cable, another society-altering
event occurred, one that changed the way we communicate and,
perhaps even more so, the way we think globally. The Space Age
began with the launch of the Soviet satellite Sputnik on October
4, 1957. Satellite communications provided reliable long distance communications by augmenting or replacing cables. This
created the demand for reliable, anytime, anywhere communications.
The beginning of an idea for a truly mobile, global society
was planted; the capability to link people around the world
with nearly instantaneous voice and data communications was a
reality, but it was still fixed point-to-point communications.
The Space Age brought changes to the way we think and
the technology we create. It brought us integrated circuits,
fiber optics, photonics, ceramics, freeze-dried food, and ultimately
digital electronics. Digital technology enabled the creation
of computers, as we know them today, and the
transmission of data at higher speeds. It also provided wireless,
high-bandwidth communications. Communications satellites
and transoceanic cables—including technologically advanced
fiber optic cables with high bandwidth—continue to be
installed around the world.
It took almost 26 years after Sputnik before cellular communications
brought mobile voice communications to the
masses (at least those who could afford $4,500 for a mobile
phone in December of 1983). Mobile data took a couple more
years to become common, but speed and reliability remained
issues to its success. Outside the military, access to large databases
of information was still limited to commercial and educational
institutions with their internal mainframe computers.
(Because sharing this data over wireless connections has been
impractical, data networks have remained mostly wired.)
During the 1980s, no compelling need for wireless data transmission
existed. That was about to change…. Figure 1-1 illustrates
the communication timeline.