Questions tagged [timing]

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Timing Jitter in PLLs

Regarding white (uncorrelated) and coloured (correlated) timing jitter. I know that for free-running oscillators (such as VCOs), various kinds of noise causes the jitter, for example (1/f) coloured ...
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How to make the error of the Gardner timing error detector not depend on signal amplitude?

I have implemented a Gardner timing error detector with an interpolator and timing recovery in software. I noticed that the error term of the Gardner TED depends on the signal amplitude, which causes ...
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Band-edge timing error detector, time accumulator

im trying to implement a band-edge FLL and timing locked loop from this paper (https://www.researchgate.net/publication/261499267_Band_edge_filters_perform_non_data-...
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4 votes
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Actual Sample Rate slightly off?

When capturing microphone audio, I noticed that my static buffer eventually overflows. So I timed the samples, and low and behold I'm getting an actual sample rate of 44102-ish Hz (my timer is very ...
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A-GPS frequency (fd) search ranges

A-GPS is able to reduce the fd search range from several kHz (GPS search range) to several hundred Hz (a-GPS search range). I know the GPS search range has a center at 0 Hz. What is the center ...
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GPS timing and computational complexity

I have been using Garmin GPS device for years. Just curious which algorithm is used in the device: Navigation equations that can calculate both GPS device's position and its clock bias. In this way, ...
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Isn't Gardner's algorithm and Early-Late gate the same thing?

I'm reading about some symbol synchronization methods and I find these two (ELG and Gardner) very similar. Early-Late gate takes 2 samples, one at $t=T-\delta$ and the other at $t=T+\delta$, then ...
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Sampling multiple sensors at different rates

I have a question regarding how best to sample data from multiple sensors when they are all updating at different/changing rates. I am new to data acquisition so please bear with me. For my Master's ...
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How can I perform timing recovery from the envelope of PSK signals?

I'm trying to reimplement FDMDV in GNU Radio, largely for educational purposes. It consists of 15 PSK subcarriers, 75 Hz apart, 50 symbols/sec each. The center one is BPSK and alternates phase each ...
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3 votes
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Gardner Timing Recovery for Repeated Symbols

I am implementing the Gardner Timing Error Detection algorithm for a QPSK signal. I understand the concepts behind it but I am curious as to what effect repeated signals can have on the phase lock. ...
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Gardner timing recovery and constellation diagram

I would like to ask for some guidance regarding 2 issues mainly QPSK and Gardner algorithm for timing recovery. I am having as input a set of IQ samples (10 samples per symbol) to which I need to ...
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"Time To Lock" in Bit Timing Synchronisation

In the context of bit timing synchronisation in digital communications, what is meant by the requirement that says the "Time to lock to a sampling point should be no more than X symbols"? There seems ...
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Sampling Clock Offset estimation

I want to estimate sampling clock offset. I am currently referring this paper " CRAMER-RAO BOUNDS FOR DATA-AIDED SAMPLING CLOCK OFFSET AND CHANNEL ESTIMATION ". Is there any other method to estimate? ...
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Practical Gardner timing error implementation

I'm trying to demodulate a QPSK communication. For the moment I do: Signal detection by computing the ratio between the power of the carrier wave compared to the signal power. Initial clock ...
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What effect does mutipath have on estimating optimal sampling time using the averaging method described therein

This question takes off from this question regarding syncronization of BPSK signals. For the sake of argument let us assume 10 samples make up 1 bit. One method currently suggested is break up the ...
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How to determine where to sample for demodulation of BPSK signals?

I have a simple BPSK demodulator. Very simply, the signal comes in and is split into two branches, one for I and one for Q. The I branch is mixed with a sin wave of the carrier, and the Q branch ...
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