|
Two-tone Testing
Two-tone testing is a means of testing electronic components and systems, particularly radio systems, for intermodulation distortion. It consists of simultaneously injecting two sinusoidal signals of different frequency, frequencies (tones) into the component or system. Intermodulation distortion usually occurs in active components like amplifiers, but can also occur in some circumstances in passive items such as cable connectors, especially at high power. Measurement in two-tone testing is most commonly done by examining the output of the device under test (DUT) with a spectrum analyser with which intermodulation products can be directly observed. Sometimes this is not possible with complete systems and instead the consequences of intermodulation are observed. For instance, in a radar system the result of intermodulation might be the generation of false targets. Rationale An electronic device can be tested by applying a single frequency to its input and measuring the respons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attenuator (electronics)
An attenuator is a Passivity (engineering), passive wideband, broadband Electronics, electronic device that reduces the Electric power, power of a signal without appreciably distortion, distorting its waveform. An attenuator is effectively the opposite of an amplifier, though the two work by different methods. While an amplifier provides gain (electronics), gain, an attenuator provides loss, or gain less than unity. An attenuator is often referred to as a "pad" in audio electronics. Construction and usage Attenuators are usually Passivity (engineering), passive devices made from simple voltage divider networks. Switching between different resistances forms adjustable stepped attenuators and continuously adjustable ones using potentiometers. For higher frequencies precisely matched low Standing wave ratio, voltage standing wave ratio (VSWR) Electrical resistance, resistance networks are used. Fixed attenuators in circuits are used to lower voltage, Dissipation, dissipate power, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Port (circuit Theory)
In electrical circuit theory, a port is a pair of terminals connecting an electrical network or circuit to an external circuit, as a point of entry or exit for electrical energy. A port consists of two nodes (terminals) connected to an outside circuit which meets the ''port condition'' – the currents flowing into the two nodes must be equal and opposite. The use of ports helps to reduce the complexity of circuit analysis. Many common electronic devices and circuit blocks, such as transistors, transformers, electronic filters, and amplifiers, are analyzed in terms of ports. In multiport network analysis, the circuit is regarded as a "black box" connected to the outside world through its ports. The ports are points where input signals are applied or output signals taken. Its behavior is completely specified by a matrix of parameters relating the voltage and current at its ports, so the internal makeup or design of the circuit need not be considered, or even known, in de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directional Coupler
Power dividers (also power splitters and, when used in reverse, power combiners) and directional couplers are passive devices used mostly in the field of radio technology. They couple a defined amount of the electromagnetic power in a transmission line to a port enabling the signal to be used in another circuit. An essential feature of directional couplers is that they only couple power flowing in one direction. Power entering the output port is coupled to the isolated port but not to the coupled port. A directional coupler designed to split power equally between two ports is called a hybrid coupler. Directional couplers are most frequently constructed from two coupled transmission lines set close enough together such that energy passing through one is coupled to the other. This technique is favoured at the microwave frequencies where transmission line designs are commonly used to implement many circuit elements. However, lumped component devices are also possible at lower ... [...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] |
Two Tone Rx Test (off Air)
2 (two) is a number, numeral and digit. It is the natural number following 1 and preceding 3. It is the smallest and the only even prime number. Because it forms the basis of a duality, it has religious and spiritual significance in many cultures. Mathematics The number 2 is the second natural number after 1. Each natural number, including 2, is constructed by succession, that is, by adding 1 to the previous natural number. 2 is the smallest and the only even prime number, and the first Ramanujan prime. It is also the first superior highly composite number, and the first colossally abundant number. An integer is determined to be even if it is divisible by two. When written in base 10, all multiples of 2 will end in 0, 2, 4, 6, or 8; more generally, in any even base, even numbers will end with an even digit. A digon is a polygon with two sides (or edges) and two vertices. Two distinct points in a plane are always sufficient to define a unique line in a nontri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MIL-STD-461
MIL-STD-461 is a United States Military Standard A United States defense standard, often called a military standard, "MIL-STD", "MIL-SPEC", or (informally) "MilSpecs", is used to help achieve standardization objectives by the United States Department of Defense. Standardization is beneficial ... that describes how to test equipment for electromagnetic compatibility. The United States Department of Defense issued MIL-STD-461 in 1967 to integrate electromagnetic compatibility into the research and development stage for defense communications technology. Various revisions of MIL-STD-461 have been released. Many military contracts require compliance to MIL-STD-461E. The latest revision (as of 2015) is known as "MIL-STD-461G". While MIL-STD-461 compliance is technically not required outside the US military, many civilian organizations also use this document. In 1999, MIL-STD-462 was combined with MIL-STD-461D into MIL-STD-461E. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEC 62037
The International Electrotechnical Commission (IEC; ) is an international standards organization that prepares and publishes international standards for all electrical, electronic and related technologies. IEC standards cover a vast range of technologies within electrotechnology. The numbers of older IEC standards were converted in 1997 by adding 60000; for example IEC 27 became IEC 60027. IEC standards often have multiple sub-part documents; only the main title for the standard is listed here. * IEC 60027 Letter symbols to be used in electrical technology * IEC 60028 International standard of resistance for copper * IEC 60034 Rotating electrical machines * IEC 60038 IEC Standard Voltages * IEC 60041 Field acceptance tests to determine the hydraulic performance of hydraulic turbines, storage pumps and pump-turbines * IEC 60044 Instrument transformers * IEC 60045 Steam turbines * IEC 60050 International Electrotechnical Vocabulary * IEC 60051 Direct acting indicating analogu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Network
A cellular network or mobile network is a telecommunications network where the link to and from end nodes is wireless network, wireless and the network is distributed over land areas called ''cells'', each served by at least one fixed-location transceiver (such as a base station). These base stations provide the cell with the network coverage which can be used for transmission of voice, data, and other types of content via radio waves. Each cell's coverage area is determined by factors such as the power of the transceiver, the terrain, and the frequency band being used. A cell typically uses a different set of frequencies from neighboring cells, to avoid interference and provide guaranteed service quality within each cell. When joined together, these cells provide radio coverage over a wide geographic area. This enables numerous Mobile device, devices, including mobile phones, Tablet computer, tablets, laptops equipped with mobile broadband modems, and Wearable technology, wea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Base Station
A cell site, cell phone tower, cell base tower, or cellular base station is a cellular frequencies, cellular-enabled mobile device site where antenna (electronics), antennas and electronic communications equipment are placed (typically on a Radio masts and towers, radio mast, tower, or other raised structure) to create a cell, or adjacent cells, in a cellular network. The raised structure typically supports antenna and one or more sets of transmitter/receivers transceivers, digital signal processors, control electronics, a GPS receiver for timing (for CDMA2000/IS-95 or GSM systems), primary and backup electrical power sources, and sheltering. Multiple cellular providers often save money by mounting their antennas on a common shared mast; since separate systems use different frequencies, antennas can be located close together without interfering with each other. Some provider companies operate multiple cellular networks and similarly use colocated base stations for two or more ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon-fibre Composite
Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon composite, or just carbon, are extremely strong and light fiber-reinforced plastics that contain carbon fibers. CFRPs can be expensive to produce, but are commonly used wherever high strength-to-weight ratio and stiffness (rigidity) are required, such as aerospace, superstructures of ships, automotive, civil engineering, sports equipment, and an increasing number of consumer and technical applications. The binding polymer is often a thermoset resin such as epoxy, but other thermoset or thermoplastic polymers, such as polyester, vinyl ester, or nylon, are sometimes used. The properties of the final CFRP product can be affected by the type of additives introduced to the binding matrix (resin). The most common additive is silica, but other additiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
