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Simulink 2x1 MIMO Channel Estimation Test

I have been working on a MATLAB Simulink based Alamouti testbed for USRP software defined radio. I am using the Ettus B210.

I have implemented a very simplistic channel estimation scheme whereby I transmit each of the four QPSK constellation points on each antenna consecutively. I then receive using a single antenna, and after all of the frequency and phase synchronisation I divide what was received by the ideal constellation leading to a simple H-matrix.

Check out this video where you can see the pilot constellation change as I move the antenna! Awesome!


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