Synchronizing data transmission and reception

Hello Everyone,

I am transmitting data from one PC (with SDR) to another PC (with
The data is a IQ stream of 1s and 0s which will be read from a file and
modulated(QAM, QPSK or any other).
The data will be received at the other PC, demodulated and dumped into a
file for further analysis.

The data will be sent and received repeatedly

The problem is that I want the data to be synchronized so that
samples can be analyzed.
I thought of using a header or something but I am not able to implement
in GRC.
I only want the data to be dumped from the start.
In the beginning I am comfortable with even wired
transmission(connecting Tx
to Rx directly) but main thing is synchronization.

Please help with the flowgraph in GRC so that I can synchronize data.

Thank you

P.S - I tried packet encoder and decoder blocks but couldn’t retrieve
synchronized data.
I am using GNURadio 3.7.0 on a 64-bit Ubuntu 12.04

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