frame_sync
Frame synchronization is the problem of align the receiver and transmitter in time and frequency, this is the most complex algorithmic and computational part of the entire project and must be done in several steps.
First the preamble structure itself is of large importance and, where we can see that each preamble consists of three parts that can be distinguished from each other.
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The first part of the preamble is a number of upchrips that start at 0 and indicate the beginning of a new packet. Then the network identifers follow where the information is stored from which device the packet is and to which device the packet is heading to. Lastly the downchirps are sent and these downchirp together with the upchirps are used for synchronization,
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