Whiskbroom Sensor Vs Pushbroom Sensor-Difference between Whiskbroom Sensor and Pushbroom Sensor
This page compares Whiskbroom Sensor vs Pushbroom Sensor and mentions difference between Whiskbroom Sensor and Pushbroom Sensor or scanner types.
The figure-1 depicts Whiskbroom Sensor which uses linear or area array of detectors.
Here image is built up by movement of satellite along its orbital track and by
cross-track scanning using a mirror.
Example: LANDSAT MSS/TM
Cross-track scanner uses "back and forth" motion of the fore-optics. It scans each ground resolution cell one by one. Instantaneous FOV (Field Of View) of instrument determines pixel size.
The figure-2 depicts pushbroom sensor also known as along-track scanner.
This sensor type uses linear array of detectors aligned cross track.
Here reflected radiance passes through a lens and onto a line of detectors.
Hence scanning mirror is not needed.
Image is constructed by movement of the satellite along its orbital track.
Example: SPOT HRV (High Resolution Visible)
In this sensor type, area array can also be used for multi-spectral remote sensing. Dispersion is used in order to split light into narrow spectral bands and individual detectors.
Following table mentions comparison between Whiskbroom Sensor and Pushbroom Sensor.
|Whiskbroom Sensor||Pushbroom Sensor|
|Wide Swath Width||Narrow Swath Width|
|Complex mechanical system||Simple mechanical system|
|simple optical system||complex optical system|
|Filters and sensors are used||Dispersion grating and CCDs are used|
|Shorter dwell time||Longer dwell time|
|Pixel distortion||No pixel distortion|
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