Surveying Glossary — Letter P

A professional land survey that determines and documents the precise legal boundaries of a property parcel using field measurements and existing records.

A dimensionless geometric factor that quantifies how satellite geometry affects the accuracy of horizontal and vertical position measurements in GNSS surveying.

Phase shift measurement is a surveying technique that determines distances and positions by analyzing the phase difference between transmitted and reflected electromagnetic signals.

Photogrammetry is the science and technology of obtaining reliable information about physical objects and the environment through the process of recording, measuring, and interpreting photographic images.

A specialized surveying technique that establishes precise horizontal and vertical positioning of pipelines for design, construction, maintenance, and regulatory compliance purposes.

Pix4D Photogrammetry is a professional software platform that processes digital images captured by drones or cameras to generate precise 3D models, orthomosaics, and point clouds for surveying and mapping applications.

A detailed graphical representation of a surveyed parcel of land showing boundaries, dimensions, structures, and legal descriptions used for property documentation and conveyance.

A weighted string or cord suspended from a fixed point to establish a vertical reference line for surveying and construction measurements.

A plumb line is a simple surveying instrument consisting of a weight suspended from a string or wire used to establish a true vertical reference line for accurate measurements and construction layout.

A large collection of three-dimensional coordinate points captured by surveying instruments to represent the surface geometry of objects, terrain, or structures.

Point cloud classification is the process of automatically or manually assigning semantic labels to individual 3D points in a point cloud dataset to categorize them by object type, surface material, or functional purpose.

A computational technique that removes erroneous or extraneous data points from three-dimensional point cloud datasets to improve accuracy and clarity in surveying measurements.

Point cloud registration is the process of aligning multiple point clouds from different scans or sensors into a single coordinate system to create a unified 3D model.

Point cloud registration is the process of aligning multiple point clouds in a common coordinate system to create a unified, georeferenced 3D dataset.

A GPS/GNSS surveying technique that processes satellite data after fieldwork is complete to achieve precise positioning with centimeter-level accuracy.

A surveying method using unmanned aerial vehicles equipped with GNSS receivers that processes positioning data after flight to achieve centimeter-level accuracy without real-time corrections.

Parts Per Million (PPM) is a unit of measurement expressing the ratio of one part of a substance to one million parts of the whole, commonly used in surveying to specify measurement accuracy and instrument precision.

Precise Point Positioning (PPP) is a GNSS technique that uses corrections from a single receiver to achieve centimeter-level or better positioning accuracy without requiring ground control stations or base stations.

Precise Point Positioning (PPP) is a GNSS technique that uses satellite orbit and clock corrections to achieve centimeter-level positioning accuracy without requiring a reference ground station.

Precision refers to the consistency and repeatability of measurements, while accuracy measures how close those measurements are to the true value.

The prism constant is a correction factor representing the offset distance between a reflective prism's physical center and its effective optical center used in electronic distance measurement.

A prism reflector is a retroreflective optical device used in surveying to reflect laser signals back to total stations and other electronic measuring instruments with high precision.

A surveyed point marking the boundary intersection of adjoining land parcels, established through precise measurements and legal documentation.

A legal survey that establishes and documents the exact boundaries, dimensions, and improvements of a property parcel based on recorded deed descriptions and field measurements.