What the syllabus asks you to cover
Ground or surface wave, Space wave, duct propagation, Ionospheric or sky wave. Critical frequency, Troposphere wave. Free space propagation, Plane earth propagation.
Start here for the core ideas. A dedicated GitBook topic page was not available; this original guide is introductory. Use the syllabus checklist and references below to study the remaining details.
Choose the propagation model
Ground-wave, sky-wave and space-wave propagation describe different transmission mechanisms. Their usefulness depends on frequency, terrain, ionospheric conditions, antenna height and link geometry. Reflection, diffraction and scattering explain why a signal may arrive over several paths rather than one direct path.
Connect frequency and path loss
For an ideal unobstructed far-field link with matched polarization, the Friis relationship contains the factor . It is not a universal prediction for cluttered or near-field environments. A radio link budget combines transmit power, gains and losses using consistent linear units or decibels.
Try it
In the ideal free-space model, doubling distance adds about 6 dB of path loss. Real links may show a different change because of obstacles, fading and antenna placement.
Check your understanding
Which assumptions must hold before using a free-space model? Distinguish a propagation mechanism from a frequency-allocation rule. Use current official allocation documents for permitted bands; do not infer permissions from a propagation table.
Pause and recall
Without looking back, explain the main idea, recall a key definition or formula, and describe when it applies. Include assumptions and units where relevant. Revisit any step you could not explain.