Technique for calculating the relative velocity between two points by measuring the shift in frequency of a sound wave transmitted from one point to the other
A non-invasive study which uses sound waves to show the flow in a blood vessel and can be used to determine the degree of narrowing (percent stenosis) of the vessel A wand is placed on the skin over the vessel to be imaged This study has no risks and is not painful
shift in frequency of a wave due to the relative motion between the emitter and the receiver Frequency shift is v/lambda Radars echo are shifted twice this value because this shift must be accounted for both for the forward and for the return path
A navigation system that works by sending four radar beams of constant wave energy (8800 mHz) from the aircraft to the ground and measuring the changes in the frequency of the energy returned to the aircraft The system is completely contained within the aircraft and requires no external signal It provides aircraft position information with respect to a particular reference point and the selected course
The Doppler effect, named after a German physicist, is the apparent change in pitch of the sound that occurs when the source of the sound is moving relative to the listener For example: A car horn will sound higher in pitch as it approaches, and lower in pitch after it passes us This is one principle that is employed in a rotating speaker system like a Leslie The rapid movement of the horn to and away from the listener creates a sort of vibrato effect There are many modern effects units that simulate the Leslie sound, and also offer other types of Doppler effects
Shift in frequency caused by relative motion along the line of sight between the sensor and the observed scene In SAR, it is more formally the first derivative of the signal phase in the azimuth direction The span of useful Doppler frequencies illuminated by the antenna must be smaller than the azimuth pulse repetition frequency (prf), otherwise false image features (azimuth ambiguities) will occur
An indicator of the quality of a GPS position which takes acount of each satellites location relative to the other satellites in the constellation and their geometry in relation to the GPS receiver A low DOP value indicates a higher probability of accuracy
Directory Operational Binding Management Protocol Specified in the X 500 subspecification ITU-T X 519 (=ISO/IEC 9594-5): " defines the exchange of administrative information between two DSAs to administer operational bindings between them "