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Track Before Detect
In radar technology and similar fields, track-before-detect (TBD) is a concept according to which a signal is tracked before declaring it a target. In this approach, the sensor data about a tentative target are integrated over time and may yield detection in cases when signals from any particular time instance are too weak against clutter (low signal-to-noise ratio) to register a detected target.David L. Hall, James Llinas (2001) "Handbook of Multisensor Data Fusion",p. 10-30/ref> The TBD approach may be applied both for pure detection when the tentative target displays a very small amount of apparent motion, as well as for actual motion tracking. In the first case the problem is considerably simpler, both in terms of the amount of calculation and the complexity of algorithms.L. C. Jain, N. S. Ichalkaranje, G. Tonfoni (Eds.) (2002) "Advances in Intelligent Systems for Defence"p. 394/ref> See also * Track while scan * Vehicle tracking system A vehicle tracking system combines t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain. The term ''RADAR'' was coined in 1940 by the United States Navy as an acronym for "radio detection and ranging". The term ''radar'' has since entered English and other languages as an anacronym, a common noun, losing all capitalization. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwave domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar Tracker
A radar tracker is a component of a radar system, or an associated command and control (C2) system, that associates consecutive radar observations of the same target into Track (navigation), tracks. It is particularly useful when the radar system is reporting data from several different targets or when it is necessary to combine the data from several different radars or other sensors for data fusion. Role of the radar tracker A classical rotating air surveillance radar system detects target echoes against a background of noise. It reports these detections (known as "plots") in Polar coordinate system, polar coordinates representing the range and bearing of the target. In addition, noise in the radar receiver will occasionally exceed the detection threshold of the radar's constant false alarm rate detector and be incorrectly reported as targets (known as false alarms). The role of the radar tracker is to monitor consecutive updates from the radar system (which typically occur once ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signal-to-noise Ratio
Signal-to-noise ratio (SNR or S/N) is a measure used in science and engineering that compares the level of a desired signal to the level of background noise. SNR is defined as the ratio of signal power to noise power, often expressed in decibels. A ratio higher than 1:1 (greater than 0 dB) indicates more signal than noise. SNR is an important parameter that affects the performance and quality of systems that process or transmit signals, such as communication systems, audio systems, radar systems, imaging systems, and data acquisition systems. A high SNR means that the signal is clear and easy to detect or interpret, while a low SNR means that the signal is corrupted or obscured by noise and may be difficult to distinguish or recover. SNR can be improved by various methods, such as increasing the signal strength, reducing the noise level, filtering out unwanted noise, or using error correction techniques. SNR also determines the maximum possible amount of data that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Track While Scan
Track-while-scan (TWS) is a mode of radar operation in which the radar allocates part of its power to tracking a target or targets (up to forty with modern radar) while part of its power is allocated to scanning. It is similar to but functions differently in comparison to its counterparts range-while-search (RWS), long range search (LRS), air combat mode (ACM), velocity search with ranging (VSR) and combined radar mode (CRM). In track-while-scan mode the radar has the ability to acquire and lock/track multiple targets while simultaneously providing a view of the surrounding airspace, which in turn aids the pilot and or operator in maintaining better situational awareness. Background Early airborne radar systems generally operated purely as tracking systems, with a dedicated radar operator manually "tuning" the system to locate targets in a relatively narrow field-of-view in front of the aircraft. The searching area could be moved using a variety of methods, typically phase-shifting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vehicle Tracking System
A vehicle tracking system combines the use of automatic vehicle location in individual vehicles with software that collects these fleet data for a comprehensive picture of vehicle locations. Modern vehicle tracking systems commonly use GPS or GLONASS technology for locating the vehicle, but other types of automatic vehicle location technology can also be used. Vehicle information can be viewed on electronic maps via the Internet or specialized software. Urban public transit authorities are an increasingly common user of vehicle tracking systems, particularly in large cities. Active versus passive tracking Several types of vehicle tracking devices exist. Typically they are classified as "passive" and "active". "Passive" devices store GPS location, speed, heading and sometimes a trigger event such as key on/off, door open/closed. Once the vehicle returns to a predetermined point, the device is removed and the data downloaded to a computer for evaluation. Passive systems includ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
