# Tag Info

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What your're suggesting could likely be done with a bunch of loop antennas, like NFC type antennas, but one single antenna that size will likely not work, it would probably be way off on its resonant frequency.

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The loss tangent settings allow to define the angle of the (complex) permeability/permittivity.

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You are correct, a cell phone antenna is bombarded constantly with radio waves from other phones, broadcast radio and TV stations, satellites, wifi routers ... it is a very long list. Several systems work together to single out the one signal meant for your phone. The antenna is an efficient receptor only for a narrow range of frequencies. Next, the ...

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Probably these dimensions are used to calculate the inductance by an approximation formular. Wheeler's formular is likely used as it's often referenced when searching for such a respective approximation formular. Then $b$ is: And for $h$ you can think of printing that picture several times and placing the sheets one onto the other. Here are also ...

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From AN1445 - Antenna desugn guide for MFRC52x, PN51x and PN53x Antenna Symmetry The symmetry in antenna design is absolutely necessary with respect to tuning and EMC behavior. Otherwise common mode currents are generated to parasitic capacitances from the antenna to ground. Theses currents can cause emissions that hurt EMV regulations It can be ...

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It looks to me like that is the ground return path for the loop. If you'll notice that on the other side of the board the last loop crosses over and the 3rd coil is actually the last coil before ground. I think the main reason this was done was purely asthetical, as the current through the loop would be the same. It could change the mutual inductance ...

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Yes if the metal is ferrous it can cause problems. I worked a long time ago on a project where they mounted aerials for telemetry on moving carts on the iron chassis. The transponder failed completely. The iron basically soaks up all your flux - acts as a near short circuit.

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Since patch antennas are commonly made on pcb's, it would work. But as stated the dielectric properties of the material will of course influence the result.

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Your two metal blocks (assuming they're insulated from each other) make up a capacitor. Yes, current will flow as the capacitor charges. Then when you remove the source, the charges will find some path, however high the resistance, and the capacitor will discharge at a rate determined by the capacitance and the resistance.

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There will be a brief flow of current when you first connect the battery to the metal blocks. That current will charge the capacitance between the blocks. Once that capacitance (and other stray capacitance) is charged, there will be no further flow. If there is no leakage current between the blocks, the charge on the capacitor formed by the blocks will ...

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Passive repeaters are quite common, and are most commonly used in the communications industry for line-of-sight issues that can be helped by a repeater who's required locations don't have readily available power or it's not required. Passive repeaters can be simply a physical reflection or refraction surface, or can be two antennas connected together with ...

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First off where are you located at? That yagi you posted is for the S-band at 2.6Ghz. Most of the 4G LTE spectrum is not S-band. Sprint in the US, and some parts of Europe, China and India have limited S-band LTE. The cell system is not like Blue Tooth or WiFi. Those are using S-band(WiFi can also use 5Ghz, but you can control that to the degree of ...

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There are at several kinds of antennas which could be described as "coils of wire", with very different principles. small loop antennas are actual coils (often with ferrite rods), though they are woven differently from power inductors or actuator coils, as self-capacitance must be reduced. These are tuned by a variable capacitor which is used to complete ...

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It's ideal when the trace width ends up being the same width as your pad because the pad simply works as an extension of the transmission line. However, in most cases this is not possible, but don't panic because this is not the end of the world. When the pad is much wider than the 50Ω trace it's a good idea to have a void on the ground plane(s) immediately ...

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An old ARRL VHF Manual shows dipole diagrams like this: As in your diagram, both antenna and feedline are balanced. Feeding with coax transmission line may require a balun near the antenna feed point. The top diagram shows two half-waves end-driven by a balanced feed line. However, a half-wave dipole, unfed is also shown, suggesting that the entire length ...

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I thought that a coil of wire might be good as an antenna. There are a lot of antennas that could be described as "a coil of wire", and some of them are pretty good, but there's a lot more to antenna design than just randomly coiling wires. If this is valid would using said antenna improve reception and transmittance if used? As opposed to no antenna ...

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Short answer, probably not, no. Radio waves (RF) is a highly complex field of study, separate from traditional electronics; it would take a book to explain even the basics of RF. In essence, the antenna must be tuned to the frequency of interest. "Tuning" is both a mechanical and electrical property. "Tuning" is only good for a narrow band of frequencies ...

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Decibel, or dB, is a measure for a relation of two parameters. $Decibel = 10 \cdot log\frac{P}{P_0}$, with $P_0$ beeing the parameter you compare your signal with. For calculating the gain of an antenna, you compare the recievable power at some point with the recievable power at that same point when a simple dipole antenna is used. When the power in ...

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