Intermediate at 160, Intermode at 234, Interrogation Frequency at 247, and… — Page 391, Lesson 395

This is the index of the book — the alphabetical listing of every topic inside. I want to walk you through how to read it, because it tells you exactly where each subject lives in the book, and it gives you a preview of the ground we’ll cover together. Let’s start with the entries under I. We have Integrity Monitoring at page 319 — that’s the process that checks whether a navigation system’s output can be trusted. Intermediate at 160, Intermode at 234, Interrogation Frequency at 247, and Interrogator at pages 183, 227, and 247. An interrogator is the ground or airborne equipment that sends out the interrogation signal — the question — in a secondary radar or transponder system. The Interrogation Frequency is the specific frequency that interrogation is sent on. Then we have the Inverse Square Law at page 19 — that’s the physical law that says the strength of a signal falls off with the square of the distance from the source. Inversion at 190, Ionization Intensity at 28, Ionospheric Conditions at 309, Ionospheric Propagation at pages 24 and 313, Ionospheric Propagation Error at 317, and Ionospheric Scatter at 185. The ionosphere is the layer of the atmosphere that reflects radio waves, and these entries cover how that reflection works, how conditions change it, and the errors it introduces. Then IRS at pages 268 and 285 — that’s the Inertial Reference System, the unit that senses acceleration and rotation to track your position. Moving to J: Janus Array at pages 68 and 69 — that’s a specific arrangement of Doppler antennas. Jittered at 248 — that’s a technique where the pulse timing is deliberately varied to defeat jamming or interference. K: Kalman Filtering at 278 — that’s the mathematical process that blends data from multiple sensors to get the best position estimate. Kepler’s Laws at 305 — those are the laws of planetary motion that govern how satellites orbit the Earth. Keyed Modulation at 43 — that’s modulation where the carrier is switched on and off, like Morse code. And Kilohertz at page 5 — that’s the unit of frequency, one thousand cycles per second. Now L: L1, L2, and L3 Frequencies, all at page 308 — those are the three carrier frequencies transmitted by GPS satellites. LAAS at 319 — that’s the Local Area Augmentation System, a ground-based system that improves GPS accuracy near an airport. LADGNSS at 305 — that’s Local Area Differential GNSS, a related augmentation concept. Then we have Level 1, Level 2, Level 3, and Level 4, all at page 236 — those are the four levels of something, likely a classification of navigation performance or integrity. Level 4 RNAV at 266 — that’s the highest level of Area Navigation, RNAV, which allows precise navigation without flying directly over ground-based beacons. Limaçon at 112 — that’s a mathematical curve, and it appears in the shape of certain antenna radiation patterns. Line of Sight at pages 243 and 251 — that’s the principle that VHF and UHF signals travel in straight lines and are blocked by the Earth’s curvature. Line of Sight Range (MTR) at 78 — MTR is the Maximum Theoretical Range, the farthest distance you can receive a signal before the Earth’s curvature blocks it. LNAV at pages 268 and 277 — that’s Lateral Navigation, the GPS-based navigation mode that guides you along a horizontal path. Localizer at 148 — that’s the ILS component that gives you left-right guidance on approach. Localizer Indications at 156 — that’s how that guidance is displayed on your instruments. Locator at pages 88 and 148 — that’s a low-power NDB used as a final approach fix. And Loop Aerial at pages 59, 85, and 89 — that’s the directional antenna used in ADF to determine the bearing to a station. So this index is your map. Every one of these terms is a topic we’ll cover in depth — the definitions, the operating principles, the limitations, and the failure conditions. Right now, I just want you to see the landscape: the book is organized so you can find any subject quickly, and the page numbers tell you exactly where to look. As we go through the chapters, you’ll meet each of these terms properly, with the full technical detail behind them.