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Question about analog cell phones
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Why do analog cell phones use FM? Why not AM?
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Because hard-limiting just prior to the discriminator in an FM receiver
provides a signal-capture effect, in which the strongest of several
competing signals will be received almost free of interference.
Unless the undesired signals are nearly the same strength as the
desired one, the undesired signals are greatly suppressed.
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Do you even know if they do?
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Microwave-frequencies can be done in AM just as well as FM? Why not
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Why not use FM?
Do you know they use FM?
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use AM?
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Why ? AM is more susceptable to noise and inrterference.
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Yes, the frequency is irrelevant. FM was chosen for other reasons.
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In order to avoid "clipping" and interference with nearby stations,
the modulator signal should be attenuated prior to D-A conversion and
transmission. At the receiving end, the carrier signal should be
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Why?
Why would you use D-A conversion at the TRANSMITTER?
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amplified prior to demodulation and A-D conversion.
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A/D and D/A conversions are techniques used in digital systems, not =
analog.
However, I did not follow the logic of your statement.
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Sorry. Please ignore the A/D-D/A part. I accidentaly included it.
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It somewhat resembled the argument for audio-spectrum pre-emphasis
commonly used in recording and broadcasting, but not quite.
That part about amplifying the carrier signal prior to demodulation
made me blink, to say the least.
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Why? The idea of amplifying the carrier signal prior to demodulation
is to increase the loudness of the psychedelic heterodynes.
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Why would you use A-D conversion at the RECEIVER?
If it's an "analog phone," why is it using A-D and D-A?
Do you know what an "analog cell phone" is?
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