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Coastal ocean dynamics applications radar (CODAR) describes a type of portable, land-based, High Frequency (HF) radar developed between 1973 and 1983 at NOAA's Wave Propagation Laboratory in Boulder, Colorado. CODAR is a noninvasive system that permits to measure and map near-surface ocean currents in coastal waters. It is transportable and offers output ocean current maps on site in near real time. Moreover, using CODAR it is possible to measure waves heights and it provides an indirect estimate of local wind direction. == Equipment == CODAR utilizes a compact antenna system that consists of crossed loops and a whip for receiving and a whip for transmitting radio pulses.〔Barrick et aL, Ocean Surface Currents Mapped by Radar - Science, New Series, Vol. 198, No. 4313 (Oct. 14, 1977), pp. 138-144, http://www.jstor.org/stable/1744926 1977〕 The system can be transported by vehicle and it is capable of being operated from a portable power supply (for modern instrumentation it is recommended a minimum capacity of 1050 Watts.〔see Technical Specification sheet 2010 at http://www.marine.calpoly.edu/getwet/codar.pdf〕 CODAR is capable of operating in virtually all weather conditions (it is tolerable a temperature from 0°F (-18°C) to 90°F (32°C) 〔http://www.marine.calpoly.edu/getwet/codar.pdf〕 and the relatively small dimensions of the antenna system consent CODAR deployment even in highly populated and rocky coastal areas. However, as the signal is rapidly attenuated by land, the antenna has to be mounted as close to the surface water as possible. The Operating Frequency Range of modern equipments goes from 3 to 50 MHz and it can be programmed for unattended operation for periods of up to two weeks.〔High Frequency Radar Measurements of Coastal Ocean Parameters, CETN-I-41 6/86, Coastal Engineering Research Centre, Technical Note. http://chl.erdc.usace.army.mil/library/publications/chetn/pdf/cetn-i-41.pdf〕 The main equipment is cabled to the electronic segment, that is housed near-by in a sheltered environment and contains the system hardware, where information is stored. A minicomputer controls the radar and processes the signals and the operator can communicate with the system through a portable keyboard terminal. The raw spectral data can be processed on-line to obtain real-time outputs and the final data products can be displayed on a graphics terminal or outputted to a hardcopy plotter. Otherwise, off-line processing at a later date can be accomplished. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Coastal ocean dynamics applications radar」の詳細全文を読む スポンサード リンク
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