Radio Waves
In the modern society, radio is the most widely used medium of broadcasting and electronic communication : it plays a major role in many areas such as public safety, industrial manufacturing, processing, agriculture, transportation, entertainment, national defense, space travel, overseas communication, news reporting and weather forecasting. In radio broadcasts, they use the radio waves which can be both microwaves and longer radio waves. These are transmitted in two ways: amplitude modulation (AM ) and frequency modulation
( FM ). These two kinds of wave have many differences.
Radio waves are among the many types of electromagnetic waves that travel within the electromagnetic spectrum. Radio waves can be defined by their frequency (in hertz, after Heinich Hertz , who first produced radio waves electronically), which is number of times they pass through a complete cycle per second; or by their wavelength, which is determined by the distance (by meters) that is traveled from the crest of one wave to the crest of the next.
Radio frequencies are measured in units called kilohertz, megahertz, and gigahertz. (1 kilohertz = 1000 hertz : 1 megahertz = 106 hertz, 1 gigahertz =
109 hertz). All radio waves fall within a frequency range of 3 kilohertz, or
3000 cycles per second to 30 gigahertz. Within the range of frequencies, radio waves are further divided into two groups or bands such as very low frequency (
VLF 10-30 kHz ), low frequency (LF 30-300 KHz), medium frequency ( MF 300-3000
KHz), high frequency ( HF 3-30 MHZ) and very high frequency ( VHF 30-300MHZ).
Amplitude modulation is the oldest method of transmitting voice and music through the airwaves is by amplitude modulation. This is accomplished by combining a sound wave from a microphone, tape, record, or CD with a "carrier" radio wave. The result : a wave that transmits voice or programming as its amplitude ( intensity ) increases and decreases. Amplitude modulation is used by station broadcasting in the AM band and by most international short wave stations. Frequency modulation is another way to convey information, voice , and music on a radio wave is to slightly change, or modulate, the frequency. The main advantage of FM broadcasting is of it is static free. But the drawback to
FM is since the frequency is varied, station takes up more room on the band.
Frequency modulation is, of course, used on the FM band. And it is used for
"action band" and ham transmission in the VHF/UHF frequency range.
In amplitude modulation, what is modified is the amplitude of a carrier wave on one specific frequency.
walking across them. The lines and pulleys and some parts of the waves are example of
Radio just like the Superbowl, had a way of getting millions of people together to tune in at one particular time. The radio, along with the Superbowl, contain both entertainment/ talent while successfully throwing advertising to consumers. Both the radio and Superbowl profit from companies that provide advertising which, in turn, boosts sales for that company. Radio advertisments were used to target mainly women, whereas, Superbowl ads target both men and women. A major difference between Radio and Superbowl is the news coverage. Radio, at any point, provides news stories while the Superbowl focuses on a game. Radios competition was newspapers while the Superbowls was social media
Wire time (or panghantar such as an antenna) conducts alternating current, electromagnetic radiation is propagated at the same frequency as the electric current. Depending on the situation, electromagnetic waves can be waves or like particles. As a wave, characterized by speed (speed of light), wavelength, and frequency. When considered as particles, they are known as photons, and each has an energy associated with the frequency of the waveform shown by the Planck relationship E = Hν, where E is the photon energy, h is the Planck constant - 6.626 × 10 -34 J · s - and ν is the frequency of the
2b.The smallest waves will be created by a, and c because they are both light winds and they have the shortest distance to travel.
Traditional (AM/FM) Radio - it is currently free, but only offers a homogenous shallow play lists with medium audio quality.
moving back and forth in the same direction as the waves are traveling, as secondary or transverse shear waves, known as S
7. Megahertz (MHz, millions of hertz), and Gigahertz (GHz, billions of hertz) measure CPU frequencies, that is the maximum number of CPU pulses per second.
Every invention ever known to man had pioneers or people who contributed to the creation of the product. Radio had many pioneers that allowed for its creation and their names are Heinrich Hertz, Nikola Tesla, Ernst Alexander, Edwin Armstrong, Guglielmo Marconi, Lee DeForest, Frank Conrad, Reginald Fessenden, and Edward Armstrong. It all started with a German physicist named Heinrich Hertz who in 1884 proved that you could transmit and receive electric waves wirelessly. Hertz thought that the work he had done had no use whatsoever but little did he know that what he done is considered the fundamental building block of radio, and that is the reason why every frequency measurement is named after him (Short). In that same year a Serbian-American inventor named Nikola Tesla came to the U.S and sold patents to his inventions to a man named George Westinghouse. After that Tesla established his own lab which is where he built the tesla coil , an induction coil that is still used in radio today (Short). The next progression of radio focused on more than just the transmission of waves, the new focus was transmission of speech. The first to begin to add speech into the radio mix was Ernst Alexander, a Sweden born inventor who developed the first alternator to make speech transmission possible (Short). This was so new to the s...
Before beginning our research on radio waves, to us, radio waves were just waves going through the atmosphere, carrying sound from one place to another. Those were our ignorant days! We did not realize the complicated terms and theories involved. In the following report you will see how we advanced in our knowledge of radio waves, and we hope it will do the same for you. Radio waves are a combination of two kinds of electric vibrations.
Armstrong, A. (May 17, 2007). Satellite Radio vs. High-Definition Radio. Retreived June 19, 2009 from http://stereos.about.com/od/homestereotechnologies/a/radio.htm
Digital signals convert regular signals into strings of ones and zeros, which is much more efficient than analog signals. Broadcasters can maximize their use of channel space because digital signals carry significantly more information than analog signals. Several digital programs and services can be sent in the space occupied by a single analog channel. The result of this is that the consumer is provided with more channel choices(FCC).
Radio broadcasting was introduced to the public in the early 1920s (Potter 226). There was only one type of broadcast protocol in the 1920’s and 30’s being AM radio(The Early Years). In 1921 there were only five AM radio stations, and only about 1% of all households in this country had a receiver (Potter 226). A receiver was basically another name for a radio because at this time radios were very expensive and there were not enough radio stations to make the system work. However, in 1923 there were over 500 stations to pop up which in turn led to increased sales of receivers to the general public (Potter 226). With the popping up of more radio stations the more receivers were being bought which meant that many people in the public were tuning into these various radio stations for information and entertainment. Radio was on the rise and it seemed that there was nothing slowing it down.
"Properties of sine waves." University of Manitoba. University of Manitoba, 2010. Web. 29 Nov. 2013. .
Radio is one of the easiest and cheapest media sources. The giant advantage of radio as a part of globalization process is that it can be understood by even illiterate people and can be served to a larger number of people. Moreover it is accessible to the people who l...