Abstract—2×2 unitary precoding based on receiver feedback is applied alongside spatial multiplexing at the base station in HSDPA (D-TxAA) when the mobile terminal supports MIMO transmissios [1]. This precoding will influence achievable sumrate

MIMO technology spatial multiplexing

Current modern wireless communication is based on orthogonal frequency division multiplexing (OFDM) and the reliability of it significantly increased with the multiple inputs multiple outputs (MIMO), and there is a scope to enhance the perfor