Multimedia Engineering
  History of Multimedia

If you are of the mindset that multimedia is some phrase from the 1990's, guess again. Webster's research indicates 1962 as the earliest recorded use (in English) of the word "multimedia" which is defined as "using, involving or encompassing several media." Media (plural of medium) in this inference, represents any means, agency, or instrumentality through which a force acts or an effect is produced. The multimedia concept can be traced to Paul Nipkow, a German, who in 1884 at age 24 developed the first video disc. Nipkow combined his video disc with Guglielmo Marconi's radio components yielding the Nipkow system, which endured well into the 1920's as the standard for research in video/audio projection.

A simple example of media communications would be the telegraph, developed in the U.S. by Samuel Morse in the mid 1800's. It is an example of a communications system employing only "carrier" and medium. By developing "Morse code" he was able to turn the carrier on and off, sustaining it's presence for either a short (dot) or long (dash) duration. Easily detected by a listening station along the line, the code could be converted to letters and words.

In the wireless technologies, free space (outer space and/or inner space) is the medium that transports electromagnetism from point of transmission (sometimes an antenna fed from a transmitter) to point of reception (sometimes an antenna feeding a receiver). Sometimes it is even simpler than that, as the spoken word across the room, or the painting on the wall demonstrate to the human senses. Physicists tell us that electromagnetism can be considered a wave or a particle. Generally speaking, the electromagnetic waveforms are often modulated (mixed, or multiplexed). The two key ingredients often are divisible into two distinct groups, the information and the carrier. The information might be video, audio or data. The carrier might be a radio frequency signal of high or low power, or a mid frequency "bias" in a tape recorder, or the light from a laser diode. The carrier is needed to deliver the information to the end of the designated transmission path. In some cases a carrier is not necessary. For example, the sound waves emanating from a loudspeaker travel across the room to your ear without the aid of a carrier, but over a long distance this method of delivery will reach its distance limit. It is easy to realize the limitations of moving information over great distances without a carrier.

The wire technologies offer a different medium to deliver information waveforms from source to destination. Predominantly operating over strands of copper or aluminum (and various alloys) since their inception in the 1820's, the technology of fiber optics is currently the medium of choice in many applications. Fiber optics employs thinly drawn strands of glass to transmit lightwaves that have been modulated by the electronic waveform of your choice. In this case, light is the carrier and glass (fiber optic cable) is the medium. Once again, the carrier is generally present, but not always required. In the classic example of two paper cups connected with a string, the audio waves generated by the larynx are collected in the cup and transformed to mechanical energy which is delivered to the string. The string is the medium. There is no carrier. The vibrations are delivered to the destination cup, which transforms the mechanical energy back to sound waves which are in turn detected by the ear. Most of the wiring connecting your stereo components and video cassette recorder and television are carrying sound and picture information without the help of a carrier, with the exception of the coaxial cable (labeled "Antenna in" and/or "RF" out) which utilizes a carrier to move information. Since the coming of digital television and the migration of VHF TV stations away from channels 2 through 6, VCR/DVD combo players no longer come equipped with a built in channel 3/4 modulator. The upshot is that the FCC is now considering repopulating the lower VHF TV channels 4 through 6 with stations that have only recently moved to UHF to free some UHF upper TV channels to auction off to new technologies. If this happens, it will be the third time the UHF TV band will have been truncated.

Today, when the topic of multimedia is on the table, many people limit their view to include only the latest presentation software on their tablet or laptop which allows the simultaneous integration of text, sound, graphics, motion video and animation. The visual of a television news anchor with graphics, sound clips, and a scrolling text behind him comes to mind with the most basic presumption about multimedia presentations. To obtain a truly balanced view of multimedia, it helps to understand some of the fundamental concepts of both wireless and wired technologies before attempting to sort out the various streams of audio, video and data and the various structure of these composite and component wavefroms, whether analog or digital.