03-09-2012, 02:54 PM
BRIEF ON BVR TACTICS
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TYPES OF RADAR
The two basic types of radar are PULSE and CONTINUOUS WAVE . The PULSE radar is the more conventional radar, which transmits a burst of radar energy and then waits for the energy (or echo) to be reflected back to the antenna. After a specific period of time (depending on how far the radar is searching) another pulse will be sent followed by another listening period. Since radar waves travel at the speed of light, range from the return can be calculated.
CONTINUOUS WAVE (CW) radars transmit a constant beam of radar energy. When a CW radar illuminates a moving object (such as an aircraft or a car) the radar wave returns to a separate antenna with a frequency that is slightly higher (if the object is moving toward the radar) or lower than the frequency of the original radar energy. By measuring this change of the Doppler Shift the speed of the object can be determined.
DOPPLER SHIFT
The Doppler- Effect is the apparent change in frequency or pitch when a sound source moves either toward or away from the listener, or when the listener moves either toward or away from the sound source. This principle, discovered by the German physicist Christian Doppler, applies to all wave motion.
To understand the Doppler effect, first assume that the frequency of a sound from a source is held constant. The wavelength of the sound will also remain constant. If both the source and the receiver of the sound remain stationary, the receiver will hear the same frequency sound produced by the source. This is because the receiver is receiving the same number of waves per second that the source is producing.
JAMMER
Similar to radar but only transmits electro-magnetic frequencies in the same block band of radar in the opposite (180 deg) phase, thereby nullifying the radar frequencies effectiveness.
[attachment=33214]
TYPES OF RADAR
The two basic types of radar are PULSE and CONTINUOUS WAVE . The PULSE radar is the more conventional radar, which transmits a burst of radar energy and then waits for the energy (or echo) to be reflected back to the antenna. After a specific period of time (depending on how far the radar is searching) another pulse will be sent followed by another listening period. Since radar waves travel at the speed of light, range from the return can be calculated.
CONTINUOUS WAVE (CW) radars transmit a constant beam of radar energy. When a CW radar illuminates a moving object (such as an aircraft or a car) the radar wave returns to a separate antenna with a frequency that is slightly higher (if the object is moving toward the radar) or lower than the frequency of the original radar energy. By measuring this change of the Doppler Shift the speed of the object can be determined.
DOPPLER SHIFT
The Doppler- Effect is the apparent change in frequency or pitch when a sound source moves either toward or away from the listener, or when the listener moves either toward or away from the sound source. This principle, discovered by the German physicist Christian Doppler, applies to all wave motion.
To understand the Doppler effect, first assume that the frequency of a sound from a source is held constant. The wavelength of the sound will also remain constant. If both the source and the receiver of the sound remain stationary, the receiver will hear the same frequency sound produced by the source. This is because the receiver is receiving the same number of waves per second that the source is producing.
JAMMER
Similar to radar but only transmits electro-magnetic frequencies in the same block band of radar in the opposite (180 deg) phase, thereby nullifying the radar frequencies effectiveness.