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Questions tagged [symbol-timing]

35 questions
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FSK Demodulation, Bit Timing Recovery

I am currently implementing acoustic FSK modulation and demodulation. I am not a signal processing guy so any help about the bit timing recovery would be very appreciated. Currently I implemented the demodulator using two matched filters for each…
peter
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How to measure/estimate symbol rate of a signal with unknown ( but probably QAM ) modulation?

Is it possible to estimate the symbol rate of a signal whose modulation is not know exactly but it can only be guessed that it is probably some kind of QAM (probably 64 or 256). What is the best way to get an estimate for the symbol rate of a…
jhegedus
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Symbol time offset simulation

I ran a number of simulations for symbol timing synchronization in the past. I used GNU Radio mainly. Now, I'm trying to do the same thing in C++. To achieve that, I need a way to introduce symbol offset to the symbols. So suppose I have a complex…
Moses Browne Mwakyanjala
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Time recovery algorithm and a symbol with samples

I am working on my graduation thesis. The topic is a receiver implementation in FPGA. I am doing an implementation of symbol timing recovery. For this part I have decided to choose the Gardner algorithm. I have found here discussions about Gardner,…
Ali23
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Symbol Timing recovery for modulation producing ISI

I am interested in understanding why the common timing recovery algorithms function for modulation schemes which produce ISI. For example, suppose you are receiving at the output of a matched filter a raised cosine pulse and you are interested in…
FourierFlux
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Synchronization of BPSK with variable-length symbols (ISO 14443)

Does anyone have an idea how one would perform BPSK symbol synchronization if symbol length is allowed to vary? As dumb as that sounds, this is not a theretical question.The "Proximity" Type B NFC protocol defined in ISO/IEC 14443 has such a…
Evan Cox
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How does the Meyr-Oerder Timing Algorithm work?

I`ve came across a Paper for this Algorihm for estimating the Symbol-Timing from Meyr and Oerder, which I want to understand. The Algorithm uses blocks from the samples and calculates the Timing Estimation for the difference between the…
Chris
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Symbol timing recovery design

I am trying to design the Symbol timing recovery(#STR) block of #DVBS Receiver. These are the specifications Symbol rate ($f_s$) = $2\textrm{ MHz}$ Acquisition range = $10\%$ of Symbol rate Acquisition time = better than $50\textrm{ ms}$ …
avi1987
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Loop bandwidth for symbol timing recovery

I am trying to design the Symbol timing recovery (STR) block of DVBS Receiver. How should I chose the loop bandwidth and damping ratio for determining the loop filter coefficients $k_1$ and $k_2$? In some literature they are given as $B_nT_s=…
avi1987
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Phase and Symbol Timing recovery - Lock detection

I have a BPSK receiver that perfectly synchronizes in both phase and timing. This can be observed by looking at the convergence of Costa's loop and symbol timing recovery. My question is how to mathematically detect the lock for PLL-based algorithms…
Moses Browne Mwakyanjala
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Symbol timing recovery: Polyphase vs piecewise linear interpolation

A symbol timing recovery scheme shown below has been successfully implemented in C++. Different TEDs (Mueller & Mueller, Early-Late, Maximum Likelihood, Gardner, Zero-Crossing, etc) are included in the implementation. I use a cubic interpolator I…
Moses Browne Mwakyanjala
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symbol synchronization

PLL is typically used in carrier synchronization and its diagram is well known, consisting of a multiplier, a low pass filter, and a VCO. In "Phase-locked Loop" at wiki (https://en.wikipedia.org/wiki/Phase-locked_loop), it says in the "Application"…
Cindy
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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 from that you get the timing error; Gardner takes…
researcher9
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Fractional spaced equalizer + timing (clock) recovery

I am trying to figure out how timing recovery is used after equalization (or, being more correct, when the equalizer is in the timing recovery loop), having a T/2 fractional spaced equalizer and using the Gardner algorithm as timing error…
user1113242
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Optimal time for sampling symbol in digital receivers

I'm studying various publications about symbol timing recovery algorithms, Early-late, Mueller and Muller & Gardner. All documents I've read tells that, to minimize ISI : The optimal time for sampling the signal is at the peak of the receiver…
omnit
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