What the syllabus asks you to cover
Rectangular wave guide. Transverse electric mode, transverse magnetic mode. Antenna Radiation, Theorem and Parameters.
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.
Guide or radiate the energy
A waveguide confines an electromagnetic field; an antenna couples guided energy to a radiated field or performs the reverse operation. In a hollow metallic guide, transverse-electric and transverse-magnetic modes have cutoff frequencies. A two-conductor transmission structure can support a transverse-electromagnetic mode; do not assume every guide supports TEM.
Compare antenna quantities
Radiation pattern describes directional response. Directivity compares radiation concentration with an isotropic radiator. Gain also includes radiation efficiency. Polarization describes the electric-field orientation; mismatched polarization reduces received power. Input impedance matters for matching the feed line.
Try it
An antenna with 6 dBi gain has a linear gain of about four, since . Gain is directional; it does not mean the antenna creates power.
Check your understanding
What happens to a waveguide mode below cutoff? Distinguish beamwidth, bandwidth and polarization. Use the reference readings for mode equations, radiation resistance, effective aperture and antenna matching.
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.