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1

I am going to simplify this for you. No, you cannot use the 2.4 GHz antenna for 700 MHz. The parabolic part of the antenna may still provide a little bit of gain, but it won't work nearly as well as it did at 2.4 GHz. More importantly, the antenna is probably not passive. I base this on the fact that the band specified is very narrow if it were a purely ...


1

The gain and directivity of a parabolic dish is inversely related to the wavelength of the signal and directly related to the size (diameter) of the dish. The wavelength at 700 MHz is approximately 3.5 times greater than 2.4 GHz. Hence keeping the dish size constant and lowering the frequency (increasing the wavelength) by 3.5 will result in a drop in gain ...


4

Can I use a 2.4 GHz rated parabolic MIMO antenna for 700 MHz Verizon 4G LTE data? The gain of an antenna, that is, how much it focuses in one direction, is pretty much proportional to its size divided by the wavelength. Generally, antennas don't work (well) for frequencies they're not designed for, but you can consider a parabolic dish more of a reflector ...


1

Here what we call propagation equations : https://en.wikipedia.org/wiki/Friis_transmission_equation. To explain it with hands, the Base Station (BTS) (your celltower) is emitting a signal with a power of 100 W (+50 dBm) using an anisotropic antenna ( all directions). But this is attenuated ( power decreased) with the square of the distance to your cell ...


2

Cell towers only transmit around 10 watts usually. Sometimes up to 50 or so in urban areas. Your phone can transmit up to 2 watts. Transmit power does obviously have a big effect on the range of a signal, but it is not nearly as much as you would think due to the 1/r2 relationship of radio waves propagating out from the source. If your transmitter puts out ...


2

I like to know how much current and frequency is going through human body in this condition, and how could be calculated? Is this amount of current have any did effect on our body ? The power supplies used to charge phones do not usually have an earth pin, so the output is 'floating' at about half the mains voltage. The maximum amount of current that ...


1

The risk of using a "not-so-smart" phone while being charged is if the phone detect the battery has reached full charge and stays ON , because it has only one current sensor for both battery and phone load. What this means is the battery could spend too long during CV mode and while getting warm at the same time and result in a higher risk of catastrophic ...


0

Even finding ERP a 10 m is difficult. Peak power allowed in the USA can be found near 500 wars per channel. Likely typical power near 100 watts per channel. Intensity measures such as watts per meter are not so easy to obtain because the average number of channels are not included.


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