High Resolution Remote Sensing

These flashcards cover key vocabulary and concepts related to High Resolution Remote Sensing, focusing on remote sensing techniques, resolutions, and applications.

Resolution

In remote sensing, it refers to the detail or quality of the data captured, including aspects like spatial, spectral, radiometric, and temporal resolution.

Spatial Resolution

Refers to the amount of detail visible in an image, measured by the size of pixels, e.g., Landsat TM = 30 m, Sentinel-2 = 10 m.

Spectral Resolution

Describes how a sensor samples the spectral curve, indicating the number of spectral bands captured, e.g., multispectral has 4-20 bands while hyperspectral can have hundreds.

Radiometric Resolution

The number of brightness levels an imaging system can record, also known as radiometric sensitivity, expressed in bits.

Temporal Resolution

A measure of the frequency of data acquisition, indicating how often a specific location is observed by the sensor.

Uncrewed Aerial Vehicles (UAVs)

Drones that are used for remote sensing, evolving from military uses to various commercial applications.

Multispectral Imagery

Data captured in a few broad spectral bands, allowing discrimination of materials but not identification.

Hyperspectral Imagery

Optical data with many narrow bands that can identify materials by representing detailed spectral signatures.

Spectral Mixture Analysis

A technique in remote sensing that assumes pixel reflectance is a linear combination of reflectance from different endmembers.

Structure from Motion (SfM)

A photogrammetric technique that creates 3D models from overlapping 2D images by matching features across the images.

Principal Component Analysis (PCA)

A dimensionality reduction method that simplifies hyperspectral data to a few principal components while retaining variance.

Georeferencing

The process of associating image data with real-world coordinates using GPS data and ground control points.

Cloud-Free Composites

Images that combine multiple captures to create a clearer view by averaging or selecting cloud-free observations.

Spectral Profiles

Graphs showing the reflectance of materials across different wavelengths, critical for identifying materials in hyperspectral data.

Visual Line of Sight (VLOS)

A regulatory requirement for UAV operations, meaning the pilot must keep the drone within sight during flight.

Dimensionality Reduction

The process of simplifying dataset complexity while maintaining essential information, often used in hyperspectral data analysis.