Questions tagged [demodulation]
The demodulation tag has no usage guidance.
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Why do we need a diode in an AM demodulation circuit?
The incoming signal is a modulated carrier wave, right? If we only apply a low-pass filter to it, we will get an AC signal that can be passed to a speaker directly, right?
Using a diode, we end up ...
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Synchronous demodulation
In the analog switch-based synchronous demodulation of a signal, say 1 MHz, how does the turn-on and turn-off time of the switch impact the demodulated and filtered DC output (demodulation here is ...
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Frequency demodulation circuit
This is how I designed the frequency modulation circuit, but I cannot perform the demodulation process. It can be done with a PLL but I couldn't install it. How can I demodulate?
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Reading a spectrum analyser in MATLAB
When demodulating an AM waveform why is there a frequency spike on the spectrum analyser of exactly two times the carrier frequency with an upper and lower sideband. It is past the cut off frequency ...
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What Exactly Is Meant by a 2nd Order Phase Locked Loop?
I'm teaching myself about polyphase clock sync for demodulation of OQPSK. An article from gnuradio.org entitled "Polyphase Clock Sync" makes references to a 2nd order loop. The context seems ...
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How can I design a beta modulator block
I am simulating a block beta modulator, but the problem is to switch uses in that block. What component do I have to use in place of U3? I did not find this type of any component in LTspice library ...
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Simple detection of a transient FM frequency shift
I have an application with a 2D array of inductive sensors for position detection of an object on a plane. I have experimented with inductance to digital converters (https://www.ti.com/product/LDC1314)...
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Reverse engineering key fob RF signals
I have been trying to decode the signal of a keyfob with a cheap 315MHz RF receiver (XY-MK-5V) and a ...
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Simple envelope detector
I demodulated a signal using this simple envelope detector. When I checked the output, the amplitude was decreased - it was not the same as the original signal that was modulated (from the forward ...
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FM demodulation circuit
I'm doing an FM demodulator circuit. I am copying the circuit from LTspice in the first image) to Multsim (the second image.)
Is what I did in Multisim correct? How can I get a graph from Multisim ...
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Name of RF demodulation technique using a demultiplexer
I can't remember the name of a demodulation technique I read the whitepaper on. My memory is not exact but I remember the following vaugely:
Core to it is a 1:4 demultiplexer run at 4x the desired ...
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What is the motivation behind ADA2200-style half-wave synchronous demodulator?
I came across an interesting IC that contains most components of a little lock-in amplifier (except output LPF) - ADA2200. I am curious however why they opted for such a design where instead of ...
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BPSK demodulation on scilab
I have a csv file which contains the time and magnitude of the BPSK modulated waveform. I now want to demodulate this. Its bitrate is fc/128 (~106 kbit/s) and the carrier frequency is fc/16 (~847 kHz)....
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Analog television: What is the difference between the first IF and second (demodulated) IF?
I am trying to understand what kind of changes occur to a signal in the chips which sit between the tuner and, for example the FM audio demodulator.
Take the attached example - the TDA2546A. It takes ...
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