Synthetic Aperture Radar (SAR):-
To know about SAR let us initially learn about RADAR
Does anyone have any idea about this?
RADAR:-
OK! Let me say what's RADAR first. RAdio Detection And Ranging(RADAR) may be a quite system which uses radio waves to detect the space,velocity,speed and a lot more. This object detection and distance calculation within the RADAR will help us to possess the SAR. Here, we use it for detecting our desired objects. It may be any kind of object, we'll get a definite image about the structure of the item. Moreover we will convert it into 2D images by taking picture shots and 3D structures by 3D reconstruction method. Got confused ah? don't be concerned. Further details will help to urge cleared.
SAR:-
SAR is capable of high-resolution remote sensing and also it can select their frequencies to avoid weather-caused signal attention, so it's independent of weather and altitude. we will use SAR in both day and night because it has that much imaging capability.
Working:-
Synthetic Aperture Radar (SAR) may be a coherent mostly airborne or spaceborne side-looking radar system which utilizes the flight path of the platform to simulate a particularly large antenna or aperture electronically, and that is why it generates high-resolution remote sensing imagery. Over the time, individual transmit or receive cycles (PRT's) are completed with the information from each cycle being stored electronically. The signal processing uses the magnitude and also the phase of the received signals over successive pulses from elements of an artificial aperture to form the ultimate image. After a given number of cycles, the stored data is recombined (taking under consideration the Doppler effects inherent within the different transmitter to focus on geometry in each and each succeeding cycle) to form a high-resolution image of the terrain being overflown.
The SAR works similar to a phased array, but contrary to an outsized number of the parallel antenna elements of a phased array, SAR uses one antenna in time-multiplex which results in both advantages and downsides. the various geometric positions of the antenna elements are results of the moving platform now.
The SAR-processor stores all the radar returned signals, as amplitudes and phases, for the fundamental quantity T from position A to D. Now it's possible to reconstruct the signal which might are obtained by an antenna of length v*T, where v is that the platform speed. because the line of sight direction changes along the radar platform trajectory, an artificial aperture is produced by signal processing that has the effect of lengthening the antenna. Making T large makes the Synthetic Aperture large and hence a better resolution may be achieved.
Result:-
As a target (like a ship) first enters the radar beam, the backscattered echoes from each transmitted pulse begin to be recorded. because the platform continues to maneuver forward, all echoes from the target for every pulse are recorded during the whole time that the target is within the beam. The purpose at which the target leaves the view of the radar beam it slows later, determines the length of the synthesized or stimulated antenna as like SONAR, LASER just like the one. The synthesized expanding beamwidth, combined with the increased time,the target is within the beam as ground range increases, balancing one another, such that the resolution remains constant across the whole swath.
Resolution:-
The highest obtainable azimuth resolution of a SAR is approximately equal to one-half the length of the actual antenna and does not depend on platform altitude(distance). This way of precise scanning the things, will allow us to construct and review the objects from various angles easily by transmitting the sound waves which are easy by transmitting the sound waves which are easily reflectable than anything like LASER, IR, etc.. Hopefully, we get the clear image of what they actually look like.
By,
Harish L
19BEC017
To know about SAR let us initially learn about RADAR
Does anyone have any idea about this?
RADAR:-
OK! Let me say what's RADAR first. RAdio Detection And Ranging(RADAR) may be a quite system which uses radio waves to detect the space,velocity,speed and a lot more. This object detection and distance calculation within the RADAR will help us to possess the SAR. Here, we use it for detecting our desired objects. It may be any kind of object, we'll get a definite image about the structure of the item. Moreover we will convert it into 2D images by taking picture shots and 3D structures by 3D reconstruction method. Got confused ah? don't be concerned. Further details will help to urge cleared.
SAR:-
SAR is capable of high-resolution remote sensing and also it can select their frequencies to avoid weather-caused signal attention, so it's independent of weather and altitude. we will use SAR in both day and night because it has that much imaging capability.
Working:-
Synthetic Aperture Radar (SAR) may be a coherent mostly airborne or spaceborne side-looking radar system which utilizes the flight path of the platform to simulate a particularly large antenna or aperture electronically, and that is why it generates high-resolution remote sensing imagery. Over the time, individual transmit or receive cycles (PRT's) are completed with the information from each cycle being stored electronically. The signal processing uses the magnitude and also the phase of the received signals over successive pulses from elements of an artificial aperture to form the ultimate image. After a given number of cycles, the stored data is recombined (taking under consideration the Doppler effects inherent within the different transmitter to focus on geometry in each and each succeeding cycle) to form a high-resolution image of the terrain being overflown.
The SAR works similar to a phased array, but contrary to an outsized number of the parallel antenna elements of a phased array, SAR uses one antenna in time-multiplex which results in both advantages and downsides. the various geometric positions of the antenna elements are results of the moving platform now.
The SAR-processor stores all the radar returned signals, as amplitudes and phases, for the fundamental quantity T from position A to D. Now it's possible to reconstruct the signal which might are obtained by an antenna of length v*T, where v is that the platform speed. because the line of sight direction changes along the radar platform trajectory, an artificial aperture is produced by signal processing that has the effect of lengthening the antenna. Making T large makes the Synthetic Aperture large and hence a better resolution may be achieved.
Result:-
As a target (like a ship) first enters the radar beam, the backscattered echoes from each transmitted pulse begin to be recorded. because the platform continues to maneuver forward, all echoes from the target for every pulse are recorded during the whole time that the target is within the beam. The purpose at which the target leaves the view of the radar beam it slows later, determines the length of the synthesized or stimulated antenna as like SONAR, LASER just like the one. The synthesized expanding beamwidth, combined with the increased time,the target is within the beam as ground range increases, balancing one another, such that the resolution remains constant across the whole swath.
Resolution:-
The highest obtainable azimuth resolution of a SAR is approximately equal to one-half the length of the actual antenna and does not depend on platform altitude(distance). This way of precise scanning the things, will allow us to construct and review the objects from various angles easily by transmitting the sound waves which are easy by transmitting the sound waves which are easily reflectable than anything like LASER, IR, etc.. Hopefully, we get the clear image of what they actually look like.
By,
Harish L
19BEC017
No comments:
Post a Comment