Differences

This shows you the differences between two versions of the page.

--- en:antennas [2019/04/17 12:18] – fluktuacia
+++ en:antennas [2019/04/18 14:39] – fluktuacia
@@ Line 72: / Line 72: @@
 ==== Preamplifier LNA01A ====
-Good quality preamplifier is essential due to antenna's low gain and low intensities of reflected signal.
+A good quality preamplifier is essential due to loses during signal propagation via antenna and due to low intensities of reflected signal.
-[[http://www.mlab.cz/Modules/CommRF/LNA01A/LNA01A_Bottom_Small.JPG|LNA01A]] represents a preamplifier designed for meteor detection in 2m band. It amplifies the signal from antenna and thus decrease the effect of receiver's own noise. It further reduces complications connected with signal transmission via coaxial cable (it compensates for the cable attenuation and so it is possible to use cheaper coaxial cable of RG58 type).
+[[http://www.mlab.cz/Modules/CommRF/LNA01A/LNA01A_Bottom_Small.JPG|LNA01A]] is a preamplifier designed for meteor detection in 2m band. Its benefit is mainly in amplification of signal from antenna (thus decreasing the influence of antenna’s lead (?? svod antény) and the noise from receiver). Furthermore it reduces complications connected to signal radiation from receiver’s oscillator.
 {{cs:antennas:gp_plast16.jpg?direct&300 | }}
 {{cs:antennas:gp_plast17.jpg?direct&300 | }}
+Preamplifier is therefore always installed in the immediate proximity of antenna in an plastic waterproof wiring box.
-==== Further improvements ====
+==== Modelling tools ====
-Antenna should fulfil these requirements.
+  * [[http://www.qsl.net/kd2bd/splat.html|RF Signal Propagation, Loss, And Terrain analysis tool for the electromagnetic spectrum between 20 MHz and 20 GHz.]]
+  * [[http://en.wikipedia.org/wiki/Numerical_Electromagnetics_Code|NEC2 software]]
+  * [[https://github.com/BogdanDIA/nec2-array|Antenna field in v NEC2]]
-  * It should have larger gain than currently used Ground Plane.
-  * Radiation pattern should not reach zero at zenith.
-  * It should have hemispheric radiation pattern.
-  * It should be possible to integrate it with an amplifier.
-  * Radiation pattern and directionality should be made adjustable via phasing of more antennas.