To help you get acquainted with our business, we have collected here some acronyms and phrases that are part of our everyday work.

## Tomography and X-ray imaging

http://en.wikipedia.org/wiki/Tomography

CT | Computed Tomography http://en.wikipedia.org/wiki/X-ray_computed_tomography |

NDT | Non Destructive Testing http://en.wikipedia.org/wiki/Nondestructive_testing |

MRI | Magnetic Resonance Imaging http://en.wikipedia.org/wiki/Mri, not in our focus. |

SI | Statistical Inversion. Bayesian approach to inverse problems, where all model variables are handled as random variables. http://www.springer.com/mathematics/computational+science+%26+engineerin... |

FBP | Filtered Back Projection, a technique that is used in FDK algorithm. http://en.wikipedia.org/wiki/Filtered_back_projection#Dual_transform |

FDK | The algorithm of Feldkamp, David, Kress (1984) is a basic and traditional back-projection algorithm for three-dimensional image reconstruction from cone-beam projections. |

ART, SART, MART | (Multiplicative / Simultaneous) algebraic Reconstruction Technique. These are iterative tomographic reconstruction algorithms. http://en.wikipedia.org/wiki/Algebraic_Reconstruction_Technique |

OSEM | Ordered-Subsets Expectation Maximization, iterative method used in computer tomography. http://en.wikipedia.org/wiki/Osem_(mathematics) |

MCMC | Markov Chain Monte Carlo method, used in statistical inversion theory. http://en.wikipedia.org/wiki/Markov_chain_Monte_Carlo |

PSIG | Parallel Statistical Inversion alGorithm. Advanced reconstruction method by Eigenor. |

CR |
Computed Radiography. Refers to X-ray radiography that uses an imaging plate instead |

DR | Digital Radiography. X-ray projections are acquired directly with a digital sensor. Basic feature in CT imaging devices. Also sometimes referred to Direct Radiography. |

FPD | Flat Panel Detector. |

PACS | Picture Archiving and Communication System, an image storage and communication system mostly for medical images. |

FoV | Field of view |

Voxel | Volume element. Three-dimensional cube of data. |

IP | Imaging Plate |

CAT | Computerized axial tomography scan |

## Radar

http://en.wikipedia.org/wiki/Radar

http://www.radartutorial.eu/index.en.html

PRT, PRF, PRI | Pulse Repetition Time, Pulse Repetition Frequency, Pulse Repetition Interval. These all describe how often a pulse in sent from radar in different metrics. http://en.wikipedia.org/wiki/Pulse_repetition_frequency |

SMPRF | Simultaneous Multi Pulse Repetition Frequency, also a trademark of Eigenor. http://journals.ametsoc.org/doi/abs/10.1175/JAM2288.1 |

Single-PRI, Multi-PRI (/PRT/PRF) | There are a few differences if we speak about multi-PRT or multi-PRF pulsing schemes. Mainly, time intervals (example: T¹, T² and T³) between pulses are differently sequenced: Multi-PRF: T ^{1}, T^{1}, T^{1}, T^{1}, T^{2}, T^{2}, T^{2}, T^{2}, T^{3}, T^{3}, T^{3}, T^{3} and repeatMulti-PRT: T ^{1}, T^{2}, T^{3}, T^{1}, T^{2}, T^{3}, T^{1}, T^{2}, T^{3}, T^{1}, T^{2}, T^{3} and repeatThis will make a difference in signal handling and enables or disables some features depending on the scheme. Generally speaking, Multi-PRT scheme can be considered more advantageous. |

DSP | Digital Signal Processing (http://en.wikipedia.org/wiki/Digital_signal_processing). When we speak about it in radar contexts, we usually mean analog to digital conversions and filtering that is done on hardware. |

I/Q data | Radar data that is represented as complex values in digital format. Input for our radar software. |

GC | Ground Clutter, powerful echo that earth and other nearby targets (e.g. houses) produce that usually ruins radar data from close ranges. http://en.wikipedia.org/wiki/Ground_clutter#Clutter |

ACF | Auto Correlation Function, http://en.wikipedia.org/wiki/Autocorrelation_function |

SNR | Signal to Noise Ratio, describes the relationship between noisy data and real data in radar measurement. http://en.wikipedia.org/wiki/Signal-to-noise_ratio |

Doppler speed (of an object) | Speed vector (of an object) that is perpendicular to the radar. http://en.wikipedia.org/wiki/Doppler_effect |

Dual Polarization | Modern radars can send their pulses in two of polarizations. Typical radar pulse is a mixture of H(orizontal) and V(ertical) channels. The receiving is done on both channels as well. Many of the radar echoes have a different kind of echo in the other channel. |

H | Horizontal polarization or channel. http://en.wikipedia.org/wiki/Weather_radar#Polarization |

V | Vertical polarization or channel. http://en.wikipedia.org/wiki/Weather_radar#Polarization |

dBZ | Unit of reflectivity. |

X, C, Ka, Ku, W (band) | Radar bands of different wavelengths are used in radars, since they can detect different phenomena. Some bands are technically also very hard to implement in sending and receiving sense. http://en.wikipedia.org/wiki/Radar#Frequency_bands |

## Computer Science

GPU | Graphical Processing Unit i.e. graphics card of the computer, a very powerful tool for parallel calculations. http://en.wikipedia.org/wiki/Graphics_processing_unit |

CPU | Central Processing Unit, i.e. central calculation unit of the computer. http://en.wikipedia.org/wiki/Cpu |

AVX | Advanced Vector Extensions, new features, instructions and coding schemes in x86 architecture in microprocessors from Intel and AMD http://en.wikipedia.org/wiki/Advanced_Vector_Extensions |

OpenCL | One of the possible methods to utilize GPUs as multipurpose calculation units, implemented in Eigenors products. http://en.wikipedia.org/wiki/OpenCL |