Questions tagged [polarization]
The polarization tag has no usage guidance.
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Would two perpendicular dipoles work to avoid polarization mismatch?
What would happen if you made an antenna consisting of two perpendicular dipoles tuned for the same frequency and connected to the same feed line? Would this work to avoid polarization mismatch loss?
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How can cross-polarization loss be determined given the angle between two antennas?
This question addresses the case where two antennas are exactly 90° cross-polarized, but not other angles.
How can I determine the theoretical, and estimate the actual, attenuation from cross-...
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Which way is a yagi polarized?
I am installing a yagi antenna that will receive signals from multiple omni antennas that are vertically polarized. Which way should the elements of the yagi point to match? Up and down, or horizontal?...
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Coupling 2 Antennas to one line?
Imagine two dipole (or Yagi) antennas as might be used to create a circularly polarized combination antenna. The two are physically oriented (rotated) by 90 deg, and if in the same receiving plane, ...
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Dual Polarization Yagi Antenna for 10 m
Imagine that someone has built a 4 element horizontal yagi antenna for 28 MHz with elements insulated from the boom, and with the driven element not split in the middle and using a gamma match to set ...
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Receiving the ISS SSTV: dipole antenna configuration and orientation
In short
I am trying to receive SSTV Images from the ISS (145.8Mhz) and I all have is a simple "bunny ears" dipole antenna.
In what configuration (straight, vee shaped, upside down vee, ...) ...
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What are the properties of the radiation of a magnetron?
It is commonly known that electromagnetic radiation from an antenna is polarized; the electric field is parallel to the rod and the magnetic component is perpendicular to it.
What does the radiation ...
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Can I slant-polarize a bay antenna?
I am trying to work a 700mhz LTE signal with a DB2 uhf bowtie television antenna. I find the cellular signal to be horizontally polarized. Can the bowties simply be twisted 45 degrees in both ...
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How Does the Propagation of H-pol E-M Fields Compare to That of V-pol E-M Fields (other things equal)?
A rather popular belief on this topic is that h-pol is superior to v-pol. Probably that is traceable to published "far-field" patterns over a lossy ground plane generated by Method of ...
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Are circular polarized antennas on HF subject to polarization fading?
Consider the common scenario of two amateur radio operators communicating through an ionospheric channel. Typically, each station will have a linearly polarized antenna, like a dipole or a vertical. I ...
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Why do horizontally-polarized RF waves reflect better off ground than vertically-polarized waves?
It's a well-known fact among hams who use HF frequencies that horizontally-polarized RF waves reflect better off of ground than vertically-polarized waves. This explains why ground conductivity is so ...
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Long range HF polarization
Is it possible to polarize HF signal (20-30m) at long range (thousands of km)?
It was commented in my over questions that polarization is not feasible at long range. However in this article is ...
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Variable polarization Yagi using two antennas on the same boom, joined together with variable feedpoint phase?
I have been trying for ages to find a way to mount a 10 m vertical Yagi properly, so that the mounting pole doesn't stuff up the impedance and radiation pattern, and have had no luck so far. Apart ...
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Magnetic loop antenna: vertical vs horizontal
I have a magnetic loop antenna for T/R with remote tuning. I would like to mount this in the attic horizontally. Will I loose much performance between mounting it horizontally verses vertical?
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Circular polarized antenna feed changes as I rotate it?
I had a 100cm prime focus dish laying around and I thought of making a circularly polarized feed for it, since it seemed pretty straightforward from what I've been reading. Helical feeds are supposed ...
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Why can I receive a vertically polarized signal on a horizontally polarized antenna on HF and vice versa?
One explanation I found is that a signal reflected from ionosphere is always circularly polarized. Thus it can be received by both vertically and horizontally polarized antennas (naturally, with 3 dB ...
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Which polarization for a Yagi antenna will have the best side rejection for received signals with vertical polarization?
I'm trying to null out vertical signals from a particular suburb which is about 40 kms away from my location by pointing a 4 element 10 m yagi such that the direction i want to null out is off to the ...
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Antenna polarization when dealing with satellite communications
It's easy to understand, conceptually anyway, the difference between a horizontally polarized antenna and a vertically polarized one, when referenced to ground. However, when they are pointed nearly ...
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What is the difference between "Cross Polarized" vs "Circularly Polarized" Antennas?
What is the difference between cross-polarized yagi antennas and circularly polarized antennas?
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Horizontal dipole radiation gaps
Consider the radiation pattern of a horizontal dipole mounted at a height of 1.75λ. Is it possible for a receiving station's antenna to be mounted at a certain height such that the radiation of the ...
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2 Meter horizontal or vertical dipole polarization?
When should I use one polarization over the other on 2 meters?
I've looked at the radiation patterns for horizontal dipole and seen how it changes based on mounting height. I haven't been able to ...
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Rhombic Polarization Question, provided radiation maps
I am trying to engineer my first antenna to get on the air. I need to hit a repeater 50 miles away at a lower elevation than me so that I can use its IRLP nodes. Would this mean I am looking for low ...
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Does antenna width/shape affect resonant frequency like length does?
I was wondering if I made an antenna from a Rohn 25G tower, would it have the same resonant frequency as a pole of the same height (assuming guys are insulated)? Also with the Rohn antenna, the waves ...
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Will swapping receiver polarity on a spiral antenna change right hand to left hand polarization?
I'm evaluating a helix antenna, and wanted to try out a reverse circular polarization than it's designed for. I do know that it's balanced and has no other components that would preclude polarity ...
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Should I chose a vertical or a horizontal HF antenna?
If I only have the budget for one HF antenna, should I chose a vertical or a horizontal antenna?
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