MIMO system A 26 GHz.

Is there anyone has experience designing MIMO system for 26 GHz? Why we should avoid using technique like VBLAST at 26 GHz? Also, why cross polarization technique is so popular at this frequency?

What is your applications? Microwave, Mobile Telecomm, ?
TX max power?
Receiver sensitivity?
Modulation plan?
data throughput?

it is on microwave link application.

Max. tx power around 20 dbm.

receiver sensitivity around -70 dbm.

Modulation scheme is 256 QAM.

Air link throughput 700 Mb/s.