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--- user:kurser:ham_vt2023_l8 [2023/03/07 16:18] – created ETA313-08 user
+++ user:kurser:ham_vt2023_l8 [2025/02/16 10:13] (current) – user
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 =====ETA313-08 Lab 2: Build an antenna	=====
+[[user:kurser:ham_vt2025|Back to course information]]
+Agenda: ETA to construct antennas at ETA.
+Go and search for DIY antennas online!
+===The following theory is copied from Theory Lesson 3: Antennas, Transmission lines, Propagation ===
+[[user:kurser:ham_vt2023_l7|ETA313-07]]
+Antenna = two port that converts energy from propagating in a transmission line to propagation in free-space.
+Characterized by:
+  * Input impedance, SWR, Z_in
+  * Operation frequency, resonance frequency, f_0
+  * Directivity D, antenna gain, dBi, dBd
+  * far field distance = d_f > 2*D^2/lambda, given d_f >> D, d_f >> lambda
+  * Radiation efficiency, eta
+  * radiation pattern, E & H patterns
+  * Polarization and x-pol suppression and so on...
+We can only measure input impedance and operational frequency easily with a VNA/Antena analyzer ... so lets do that at ETA.
+Different types
+  * Dipole
+  * Monopole
+  * Small loop
+  * Yagi
+  * Quad
+  * Patch
+  * Bowtie
+  * PCB/PIFA
+  * Spiral/Helical