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3-centimeter Band
The 3-centimeter or 10 GHz band is a portion of the SHF (microwave) radio spectrum internationally allocated to amateur radio and amateur satellite use on a secondary basis. The amateur radio band is between 10.00 GHz and 10.50 GHz, and the amateur satellite band is between 10.45 GHz and 10.50 GHz. The allocations are the same in all three ITU regions. List of notable frequencies *10.3681 GHz Region 2 narrow band calling frequency *10.3682 GHz Region 1 narrow band calling frequency *10.3683 to 10.3684 GHz Region 2 propagation beacons *10.36875 to 10.36899 GHz Region 1 propagation beacons Wideband FM Channels Common Wideband FM frequencies used with gunnplexers.Operation is in full-duplex with a 30 or 90 MHz split: *10.220 GHz *10.250 GHz † *10.280 GHz † *10.310 GHz *10.340 GHz *10.370 GHz ‡ *10.400 GHz *10.430 GHz † Most commonly used frequency pair for gunnplexers in North America. (10.200 to 10.300 GHz is reserved for gunnplexers in the ARRL Band Plan.) ‡ S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Super High Frequency
Super high frequency (SHF) is the ITU designation for radio frequencies (RF) in the range between 3 and 30 gigahertz (GHz). This band of frequencies is also known as the centimetre band or centimetre wave as the wavelengths range from one to ten centimetres. These frequencies fall within the microwave band, so radio waves with these frequencies are called microwaves. The small wavelength of microwaves allows them to be directed in narrow beams by aperture antennas such as parabolic dishes and horn antennas, so they are used for point-to-point communication and data links This article from the beginning of the microwave era predicted the future value of microwaves for point-to-point communication. and for radar. This frequency range is used for most radar transmitters, wireless LANs, satellite communication, microwave radio relay links, satellite phones (S band), and numerous short range terrestrial data links. They are also used for heating in industrial microwave h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microwave
Microwave is a form of electromagnetic radiation with wavelengths shorter than other radio waves but longer than infrared waves. Its wavelength ranges from about one meter to one millimeter, corresponding to frequency, frequencies between 300 MHz and 300 GHz, broadly construed. A more common definition in radio-frequency engineering is the range between 1 and 100 GHz (wavelengths between 30 cm and 3 mm), or between 1 and 3000 GHz (30 cm and 0.1 mm). In all cases, microwaves include the entire super high frequency, super high frequency (SHF) band (3 to 30 GHz, or 10 to 1 cm) at minimum. The boundaries between far infrared, terahertz radiation, microwaves, and ultra-high-frequency (UHF) are fairly arbitrary and differ between different fields of study. The prefix ' in ''microwave'' indicates that microwaves are small (having shorter wavelengths), compared to the radio waves used in prior radio technology. Frequencies in the micr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio
Amateur radio, also known as ham radio, is the use of the radio frequency radio spectrum, spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency, emergency communications. The term ''"radio amateur"'' is used to specify ''"a duly authorized person interested in radioelectric practice with a purely personal aim and without wikt:pecuniary, pecuniary interest"'' (either direct monetary or other similar reward); and to differentiate it from commercial broadcasting, public safety (police and fire), or two-way radio professional services (maritime, aviation, taxis, etc.). The amateur radio service (''amateur service'' and ''amateur-satellite service'') is established by the International Telecommunication Union (ITU) through their recommended radio regulations. National governments regulate technical and operational characteristics of transmissions and issue individual station li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Satellite
An amateur radio satellite is an artificial satellite built and used by amateur radio operators. It forms part of the Amateur-satellite service. These satellites use amateur radio frequency allocations to facilitate communication between amateur radio stations. Many amateur satellites receive an OSCAR designation, which is an acronym for Orbiting Satellite Carrying Amateur Radio. The designation is assigned by AMSAT, an organization which promotes the development and launch of amateur radio satellites. Because of the prevalence of this designation, amateur radio satellites are often referred to as OSCARs. These satellites can be used free of charge by licensed amateur radio operators for voice (Frequency modulation, FM, Single-sideband modulation, SSB) and data (AX.25, packet radio, Automatic Packet Reporting System, APRS) communications. Currently, over 18 fully operational amateur radio satellites are in orbit. They may be designed to act as repeaters, as Transponder (satel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU Region
The International Telecommunication Union (ITU), in its International Radio Regulations, divides the world into three ITU regions for the purposes of managing the global radio spectrum. Each region has its own set of frequency allocations, the main reason for defining the regions. Boundaries *Region 1 comprises Europe, Africa, the Commonwealth of Independent States, Mongolia, and the Middle East west of the Persian Gulf, including Iraq. ** The western boundary is defined by Line B and the eastern boundary is defined by Line A, except that all territory of Iran is excluded, and all territory of Armenia, Azerbaijan, Georgia, Kazakhstan, Mongolia, Uzbekistan, Kyrgyzstan, Russia, Tajikistan, Turkmenistan, Turkey and Ukraine and the area to the north of Russia which lies between lines A and C is included. *Region 2 covers the Americas including Greenland, and some of the eastern Pacific Islands. ** The eastern boundary is defined by Line B and the western boundary is defined by Line C. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Propagation Beacon
An amateur radio propagation beacon is a radio beacon, whose purpose is the investigation of the radio propagation, propagation of radio signals. Most radio propagation beacons use amateur radio frequencies. They can be found on Low frequency, LF, Medium frequency, MF, High frequency, HF, Very high frequency, VHF, Ultra high frequency, UHF, and microwave frequencies. Microwave beacons are also used as signal sources to test and calibrate antennas and receivers. The International Amateur Radio Union (IARU) and its member societies coordinate beacons established by radio amateurs. Transmission characteristics Most beacons operate in continuous wave (A1A) and transmit their identification (call sign and location). Some of them send long dashes to facilitate signal strength measurement. A small number of beacons transmit Morse code by frequency-shift keying (F1A). A few beacons transmit signals in digital modulation modes, like radioteletype (F1B) and PSK31 (G1B). Legality In the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wideband FM
Frequency modulation (FM) is a signal modulation technique used in electronic communication, originally for transmitting messages with a radio wave. In frequency modulation a carrier wave is varied in its instantaneous frequency in proportion to a property, primarily the instantaneous amplitude, of a message signal, such as an audio signal. The technology is used in telecommunications, radio broadcasting, signal processing, and computing. In analog frequency modulation, such as radio broadcasting of voice and music, the instantaneous frequency deviation, i.e. the difference between the frequency of the carrier and its center frequency, has a functional relation to the modulating signal amplitude. Digital data can be encoded and transmitted with a type of frequency modulation known as frequency-shift keying (FSK), in which the instantaneous frequency of the carrier is shifted among a set of frequencies. The frequencies may represent digits, such as ''0'' and ''1''. FSK is wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gunnplexer
A Gunn diode, also known as a transferred electron device (TED), is a form of diode, a two-terminal semiconductor electronic component, with negative differential resistance, used in high-frequency electronics. It is based on the "Gunn effect" discovered in 1962 by physicist J. B. Gunn. Its main uses are in electronic oscillators to generate microwaves, in applications such as radar speed guns, microwave relay data link transmitters, and automatic door openers. Its internal construction is unlike other diodes in that it consists only of N-doped semiconductor material, whereas most diodes consist of both P and N-doped regions. It, therefore, conducts in both directions and cannot rectify alternating current like other diodes, which is why some sources do not use the term ''diode'' but prefer TED. In the Gunn diode, three regions exist: two are heavily N-doped on each terminal, with a thin layer of lightly n-doped material between them. When a voltage is applied to the device, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duplex (telecommunications)
A duplex communication system is a point-to-point system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow for simultaneous communication in both directions between two connected parties or to provide a reverse path for the monitoring and remote adjustment of equipment in the field. There are two types of duplex communication systems: full-duplex (FDX) and half-duplex (HDX). In a full-duplex system, both parties can communicate with each other simultaneously. An example of a full-duplex device is plain old telephone service; the parties at both ends of a call can speak and be heard by the other party simultaneously. The earphone reproduces the speech of the remote party as the microphone transmits the speech of the local party. There is a two-way communication channel between them, or more strictly speaking, there are two communication channel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the south and west by the Pacific Ocean. The region includes Middle America (Americas), Middle America (comprising the Caribbean, Central America, and Mexico) and Northern America. North America covers an area of about , representing approximately 16.5% of Earth's land area and 4.8% of its total surface area. It is the third-largest continent by size after Asia and Africa, and the list of continents and continental subregions by population, fourth-largest continent by population after Asia, Africa, and Europe. , North America's population was estimated as over 592 million people in list of sovereign states and dependent territories in North America, 23 independent states, or about 7.5% of the world's popula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ARRL
The American Radio Relay League (ARRL) is the largest membership association of amateur radio enthusiasts in the United States. ARRL is a non-profit organization and was co-founded on April 6, 1914, by Hiram Percy Maxim and Clarence D. Tuska of Hartford, Connecticut. The ARRL represents the interests of amateur radio operators before federal regulatory bodies, provides technical advice and assistance to amateur radio enthusiasts, supports a number of educational programs and sponsors emergency communications service throughout the country. The ARRL has approximately 161,000 members. In addition to members in the US, the organization claims over 7,000 members in other countries. The ARRL publishes many books and a monthly membership journal called ''QST''. The ARRL is the primary representative organization of amateur radio operators to the US government. It performs this function by lobbying the United States Congress, US Congress and the Federal Communications Commission. The ARR ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
