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Ionospheric Studies
The ionosphere () is the ionized part of the upper atmosphere of Earth, from about to above sea level, a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar radiation. It plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere. It has practical importance because, among other functions, it influences radio propagation to distant places on Earth. Travel through this layer also impacts GPS signals, resulting in effects such as deflection in their path and delay in the arrival of the signal. History of discovery As early as 1839, the German mathematician and physicist Carl Friedrich Gauss postulated that an electrically conducting region of the atmosphere could account for observed variations of Earth's magnetic field. Sixty years later, Guglielmo Marconi received the first trans-Atlantic radio signal on December 12, 1901, in St. John's, Newfoundland (now in Canada) using a ki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1 Atmosphere Layers
1 (one, unit, unity) is a number, Numeral (linguistics), numeral, and glyph. It is the first and smallest Positive number, positive integer of the infinite sequence of natural numbers. This fundamental property has led to its unique uses in other fields, ranging from science to sports, where it commonly denotes the first, leading, or top thing in a group. 1 is the unit (measurement), unit of counting or measurement, a determiner for singular nouns, and a gender-neutral pronoun. Historically, the representation of 1 evolved from ancient Sumerian and Babylonian symbols to the modern Arabic numeral. In mathematics, 1 is the multiplicative identity, meaning that any number multiplied by 1 equals the same number. 1 is by convention not considered a prime number. In Digital electronics, digital technology, 1 represents the "on" state in binary code, the foundation of computing. Philosophically, 1 symbolizes the ultimate reality or source of existence in various traditions. In math ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Friedrich Gauss
Johann Carl Friedrich Gauss (; ; ; 30 April 177723 February 1855) was a German mathematician, astronomer, geodesist, and physicist, who contributed to many fields in mathematics and science. He was director of the Göttingen Observatory and professor of astronomy from 1807 until his death in 1855. While studying at the University of Göttingen, he propounded several mathematical theorems. As an independent scholar, he wrote the masterpieces '' Disquisitiones Arithmeticae'' and ''Theoria motus corporum coelestium''. Gauss produced the second and third complete proofs of the fundamental theorem of algebra. In number theory, he made numerous contributions, such as the composition law, the law of quadratic reciprocity and the Fermat polygonal number theorem. He also contributed to the theory of binary and ternary quadratic forms, the construction of the heptadecagon, and the theory of hypergeometric series. Due to Gauss' extensive and fundamental contributions to science ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Act Of 1912
The Radio Act of 1912, formally, known as "An Act to Regulate Radio Communication" (), is a United States federal law which was the country's first legislation to require licenses for radio stations. It was enacted before the introduction of broadcasting to the general public, and was eventually found to contain insufficient authority to effectively control this new service, so the Act was replaced and the government's regulatory powers increased by the passage of the Radio Act of 1927. Background Radio communication (originally known as "wireless telegraphy") was developed in the late 1890s, but it was initially largely unregulated in the United States. The Wireless Ship Act of 1910 mandated that most passenger ships exiting U.S. ports had to carry radio equipment under the supervision of qualified operators, however individual stations remained unlicensed and unregulated. This led to numerous interference issues, including conflicts between amateur radio operators and the U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur Edwin Kennelly
Arthur Edwin Kennelly (December 17, 1861 – June 18, 1939) was an American electrical engineer and mathematician. Biography Kennelly was born December 17, 1861, in Colaba, in Bombay Presidency, British India, and was educated at University College School in London. He was the son of Irish naval officer Captain David Joseph Kennelly (1831–1907) and Catherine Gibson Heycock (1839–1863). His mother died when he was three years old. In 1863, his father retired from the navy and later Arthur and his father returned to England. In 1878, his father married Ellen L.Spencer and moved the family to Sydney, Nova Scotia, when he took over the Sydney and Louisbourg Coal and Railway Company Limited. By his father's third marriage, Arthur gained four half siblings, Zaida Kennelly in 1881, David J. Kennelly Jr. in 1882, Nell K. Kennelly in 1883, and Spencer M. Kennelly in 1885. Kennelly joined Thomas Edison's West Orange laboratory in December 1887, staying until March 1894. While there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kennelly–Heaviside Layer
The Heaviside layer, sometimes called the Kennelly–Heaviside layer, named after Arthur E. Kennelly and Oliver Heaviside, is a layer of ionised gas occurring roughly between above the ground — one of several layers in the Earth's ionosphere. It is also known as the E region. It reflects medium-frequency radio waves. Because of this reflective layer, radio waves radiated into the sky can return to Earth beyond the horizon. This "skywave" or "skip" propagation technique has been used since the 1920s for radio communication at long distances, up to transcontinental distances. Propagation is affected by the time of day. During the daytime the solar wind presses this layer closer to the Earth, thereby limiting how far it can reflect radio waves. Conversely, on the night ( lee) side of the Earth, the solar wind drags the ionosphere further away, thereby greatly increasing the range which radio waves can travel by reflection. The extent of the effect is further influenced b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oliver Heaviside
Oliver Heaviside ( ; 18 May 1850 – 3 February 1925) was an English mathematician and physicist who invented a new technique for solving differential equations (equivalent to the Laplace transform), independently developed vector calculus, and rewrote Maxwell's equations in the form commonly used today. He significantly shaped the way Maxwell's equations are understood and applied in the decades following Maxwell's death. His formulation of the telegrapher's equations became commercially important during his own lifetime, after their significance went unremarked for a long while, as few others were versed at the time in his novel methodology. Although at odds with the scientific establishment for most of his life, Heaviside changed the face of telecommunications, mathematics, and science. Early life Heaviside was born in Camden Town, London, at 55 Kings Street (now Plender Street), the youngest of three children of Thomas, a draughtsman and wood engraver, and Rachel Elizabeth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glace Bay, Nova Scotia
Glace Bay (Scottish Gaelic: ''Glasbaidh'') is a community in the eastern part of the Cape Breton Regional Municipality in Nova Scotia, Canada. It forms part of the general area referred to as Industrial Cape Breton. Formerly an incorporated town (1901–1995), the municipal government in Glace Bay was dissolved and the community was amalgamated into the larger regional municipality. Prior to amalgamation, Glace Bay had been the province's fourth largest urban area and the largest town in Nova Scotia by population. Neighbouring communities include Reserve Mines, Dominion, and Tower Road. History As early as the 1720s, the French inhabited the area to supply Fortress of Louisbourg with coal. They named the location ''baie de Glace'' (literally, ''Bay of Ice'') because of the sea ice which filled the ocean each winter. In 1748, after the capture of Fortress Louisbourg, the British constructed Fort William at Table Head in order to protect a mine that produced coal to supply ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jack Belrose
John Skelton Belrose (24 November 1926 – 19 September 2024) was a Canadian radio scientist. Life and career Belrose was born in the small town of Warner, Alberta on 24 November 1926. He attended the University of Cambridge, where he was awarded a PhD in 1958. He worked for the Defence Research Telecommunications Establishment (DRTE) for 33 years. He was a member of the Canadian Amateur Radio Hall of Fame and, along with Walter Cronkite Walter Leland Cronkite Jr. (November 4, 1916 – July 17, 2009) was an American broadcast journalist who served as anchorman for the ''CBS Evening News'' from 1962 to 1981. During the 1960s and 1970s, he was often cited as "the most trust ..., was awarded the Radio Club of America's Armstrong Medal on 16 November 2007. Belrose died on 19 September 2024, at the age of 97. References External linksRemembrances of a Radio Scientist- Belrose's report on his 50th anniversary of working in the field of radio science.- a paper by Jack Belr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morse Code
Morse code is a telecommunications method which Character encoding, encodes Written language, text characters as standardized sequences of two different signal durations, called ''dots'' and ''dashes'', or ''dits'' and ''dahs''. Morse code is named after Samuel Morse, one of the early developers of the system adopted for electrical telegraphy. International Morse code encodes the 26 ISO basic Latin alphabet, basic Latin letters to , one Diacritic, accented Latin letter (), the Arabic numerals, and a small set of punctuation and procedural signals (Prosigns for Morse code, prosigns). There is no distinction between upper and lower case letters. Each Morse code symbol is formed by a sequence of ''dits'' and ''dahs''. The ''dit'' duration can vary for signal clarity and operator skill, but for any one message, once the rhythm is established, a beat (music), half-beat is the basic unit of time measurement in Morse code. The duration of a ''dah'' is three times the duration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilohertz
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose formal expression in terms of SI base units is 1/s or s−1, meaning that one hertz is one per second or the reciprocal of one second. It is used only in the case of periodic events. It is named after Heinrich Rudolf Hertz (1857–1894), the first person to provide conclusive proof of the existence of electromagnetic waves. For high frequencies, the unit is commonly expressed in multiples: kilohertz (kHz), megahertz (MHz), gigahertz (GHz), terahertz (THz). Some of the unit's most common uses are in the description of periodic waveforms and musical tones, particularly those used in radio- and audio-related applications. It is also used to describe the clock speeds at which computers and other electronics are driven. The units are sometimes also used as a representation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency
Frequency is the number of occurrences of a repeating event per unit of time. Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio signals (sound), radio waves, and light. The interval of time between events is called the period. It is the reciprocal of the frequency. For example, if a heart beats at a frequency of 120 times per minute (2 hertz), its period is one half of a second. Special definitions of frequency are used in certain contexts, such as the angular frequency in rotational or cyclical properties, when the rate of angular progress is measured. Spatial frequency is defined for properties that vary or cccur repeatedly in geometry or space. The unit of measurement of frequency in the International System of Units (SI) is the hertz, having the symbol Hz. Definitions and units For cyclical phenomena such as oscillations, waves, or for examp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spark-gap Transmitter
A spark-gap transmitter is an obsolete type of transmitter, radio transmitter which generates radio waves by means of an electric spark."Radio Transmitters, Early" in Spark-gap transmitters were the first type of radio transmitter, and were the main type used during the wireless telegraphy or "spark" era, the first three decades of radio, from 1887 to the end of World War I. German physicist Heinrich Hertz built the first experimental spark-gap transmitters in 1887, with which he proved the existence of radio waves and studied their properties. A fundamental limitation of spark-gap transmitters is that they generate a series of brief transient pulses of radio waves called Damped wave (radio transmission), damped waves; they are unable to produce the continuous waves used to carry audio signal, audio (sound) in modern AM broadcasting, AM or FM broadcasting, FM radio transmission. So spark-gap transmitters could not transmit audio, and instead transmitted information by radiotelegra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
