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Radio Fingerprinting
Radio fingerprinting is a process that identifies a cellular phone or any other radio transmitter by the ''fingerprint'' that characterizes its signal transmission and is hard to imitate. An electronic fingerprint makes it possible to identify a wireless device by its radio transmission characteristics. Radio fingerprinting is commonly used by cellular operators to prevent cloning of cell phones — a cloned device will have the same numeric equipment identity but a different radio fingerprint. Essentially, each transmitter (cell phones are just one type of radio transmitter) has a rise time signature when first keyed which is caused by the slight variations of component values during manufacture. Once the rise time signature is captured and assigned to a callsign, the use of a different transmitter using the same callsign is easily detected. Such systems are used in military signals intelligence and by radio regulatory agencies such as the U.S. Federal Communications Commission ...
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Mobile Phone
A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This radio frequency link connects to the switching systems of a mobile phone operator, providing access to the public switched telephone network (PSTN). Modern mobile telephony relies on a cellular network architecture, which is why mobile phones are often referred to as 'cell phones' in North America. Beyond traditional voice communication, digital mobile phones have evolved to support a wide range of additional services. These include text messaging, multimedia messaging, email, and internet access (via LTE, 5G NR or Wi-Fi), as well as short-range wireless technologies like Bluetooth, infrared, and ultra-wideband (UWB). Mobile phones also support a variety of multimedia capabilities, such as digital photography, video recordin ...
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Transmission (telecommunications)
In telecommunications, transmission (sometimes abbreviated as "TX") is the process of sending or propagating an Analog signal, analog or digital signal via a transmission medium, medium that is wired communication, wired, wireless, or fiber-optic communication, fiber-optic. Transmission system technologies typically refer to physical layer protocol duties such as modulation, demodulation, line coding, Equalization (communications), equalization, error control, bit synchronization and multiplexing, but it may also involve higher-layer protocol duties, for example, digitizing an analog signal, and data compression. Transmission of a digital message, or of a digitized analog signal, is known as data transmission. Examples of transmission are the sending of signals with limited duration, for example, a block or Network packet, packet of data, a phone call, or an email. See also *Radio transmitter References

Telecommunications engineering {{telecom-stub ...
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Rise Time
In electronics, when describing a voltage or current step function, rise time is the time taken by a signal to change from a specified low value to a specified high value. These values may be expressed as ratiosSee for example , and . or, equivalently, as percentages with respect to a given reference value. In analog electronics and digital electronics, these percentages are commonly the 10% and 90% (or equivalently and ) of the output step height: however, other values are commonly used. For applications in control theory, according to , rise time is defined as "''the time required for the response to rise from to of its final value''", with 0% to 100% rise time common for underdamped second order systems, 5% to 95% for critically damped and 10% to 90% for overdamped ones.Precisely, states: "''The rise time is the time required for the response to rise from x% to y% of its final value. For overdamped second order systems, the 0% to 100% rise time is normally used, and f ...
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Federal Communications Commission
The Federal Communications Commission (FCC) is an independent agency of the United States government that regulates communications by radio, television, wire, internet, wi-fi, satellite, and cable across the United States. The FCC maintains jurisdiction over the areas of broadband access, fair competition, radio frequency use, media responsibility, public safety, and homeland security. The FCC was established pursuant to the Communications Act of 1934 to replace the radio regulation functions of the previous Federal Radio Commission. The FCC took over wire communication regulation from the Interstate Commerce Commission. The FCC's mandated jurisdiction covers the 50 states, the District of Columbia, and the territories of the United States. The FCC also provides varied degrees of cooperation, oversight, and leadership for similar communications bodies in other countries in North America. The FCC is funded entirely by regulatory fees. It has an estimated fiscal-2022 budg ...
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Subscriber Mobile Radio
The subscription business model is a business model in which a customer must pay a recurring price at regular intervals for access to a product or service. The model was pioneered by publishers of books and periodicals in the 17th century. It is particularly common now for digital products, which lend themselves more naturally toward a subscription model. Subscriptions can be a more convenient, hassle-free transaction for consumers. However, due to inertia among some consumers, they may inadvertently pay for subscriptions that they no longer value because they do not realize that they are subscribed. Subscriptions Rather than selling products individually, a subscription offers periodic (daily, weekly, bi-weekly, monthly, semi-annual, yearly/annual, or seasonal) use or access to a product or service, or, in the case of performance-oriented organizations such as opera companies, tickets to the entire run of some set number of (e.g., five to fifteen) scheduled performances for a ...
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Automatic Identification And Data Capture
Automatic identification and data capture (AIDC) refers to the methods of automatically identifying objects, collecting data about them, and entering them directly into computer systems, without human involvement. Technologies typically considered as part of AIDC include QR codes, bar codes, radio frequency identification (RFID), biometrics (like iris and facial recognition system), magnetic stripes, optical character recognition (OCR), smart cards, and voice recognition. AIDC is also commonly referred to as "Automatic Identification", "Auto-ID" and "Automatic Data Capture". AIDC is the process or means of obtaining external data, particularly through the analysis of images, sounds, or videos. To capture data, a transducer is employed which converts the actual image or a sound into a digital file. The file is then stored and at a later time, it can be analyzed by a computer, or compared with other files in a database to verify identity or to provide authorization to enter a ...
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Radio-frequency Identification
Radio-frequency identification (RFID) uses electromagnetic fields to automatically Automatic identification system, identify and Tracking system, track tags attached to objects. An RFID system consists of a tiny radio transponder called a tag, a radio receiver, and a transmitter. When triggered by an electromagnetic interrogation pulse from a nearby RFID reader device, the tag transmits digital data, usually an Identifier, identifying inventory number, back to the reader. This number can be used to track inventory goods. Passive tags are powered by energy from the RFID reader's interrogating radio waves. Active tags are powered by a battery and thus can be read at a greater range from the RFID reader, up to hundreds of meters. Unlike a barcode, the tag does not need to be within the Line-of-sight propagation, line of sight of the reader, so it may be embedded in the tracked object. RFID is one method of automatic identification and data capture (AIDC). RFID tags are used in m ...
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Radio
Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3  hertz (Hz) and 300  gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna which radiates the waves. They can be received by other antennas connected to a radio receiver; this is the fundamental principle of radio communication. In addition to communication, radio is used for radar, radio navigation, remote control, remote sensing, and other applications. In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the transmitter. In radar, used to locate and track ob ...
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Mobile Telecommunications
Mobile telephony is the provision of wireless Telephony, telephone services to Mobile phone, mobile phones, distinguishing it from fixed-location telephony provided via landline phones. Traditionally, telephony specifically refers to Telephone call, voice communication, though the distinction has become less clear with the integration of additional features such as text messaging and Internet, data services. Modern mobile phones connect to a terrestrial cellular network of Base station, base stations (commonly referred to as Cell site, cell sites), using Radio wave, radio waves to facilitate communication. Satellite phone, Satellite phones use wireless links to orbiting Communications satellite, satellites, providing an alternative in areas lacking local terrestrial communication infrastructure, such as landline and cellular networks. Cellular networks, satellite networks, and landline systems are all linked to the public switched telephone network (PSTN), enabling calls to be ...
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