# Tag Info

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For maximum sensitivity preamble detection with time referencing, consider using a barker code, or for more choices with longer lengths a PRN (pseudo-random noise) sequence, or for even more choices when more distinction is needed (CDMA) Gold codes are a possibility. (Also not further detailed but have other advantages are Kasami codes and Zadoff-Chu codes)....

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You should be able to see an peak correlation as from your plot and the length of your pattern it does not appear to be noisy enough such that you would not see a peak (unless your noise is completely in the time domain as in excessive jitter that I cannot visibly see). I suspect that the pattern you are using is extending far beyond the length of the ...

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As provided pics show, there is no difference between the DC value of input and output signal of the filter i.e. they are both zero. but there is a problem in your filter design and that is, you set the 'FilterOrder' key to 1. I think its better to remove 'FilterOrder' key and its value and let the algorithm choose the smallest filter order for you. As for ...

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If the constellation at the tarsmitter is symmetric about 0 on the real line then you can simply threshold the output between -1 and +1 with 0 as the threshold. So anything above zero is a logical 1 and everything below zero is a logical 0. This detection is rule is optimal when the noise is additive.

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CRC is a "definite" indicator of the channel impacting the bits and error in received symbol. So deploying a CRC check would definitely help. Length of CRC would depend on the overall system and data packets.

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For OFDM we select the known gold sequence as the preamble or pilots. We can correctly estimate the channel(10 to 20taps). As you talked about channel delay spread, which is expressed in tap, I assume you want to track the frequency variation. This is equivalent to "correct" sampling channel frequency response. Denote $\tau_m$ the delay spread (the longest ...

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For eg. Using a length of 8 pilot samples can we detect a channel of 20 taps? If your OFDM system is sensibly designed, then, no, you need a pilot on every subcarrier. They don't necessarily have to be sent in the same OFDM symbol. "Sensible" OFDM design means that you choose your subcarrier spacing no smaller than you have to. The reason that you're doing ...

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