Abstract—Inhome Power Line Communications (PLC) enables new and highly convenient networking functions without any additional wires to mains-powered devices. Multiple Input Multiple Output (MIMO) methods can significantly increase the PLC channel throughput and the link reliability. In this paper precoded spatial multiplexing is considered in more detail since it offers the best possible data throughput in the PLC channel. Precoded spatial multiplexing requires channel state information (CSI) at the transmitter. CSI feedback possibilities as well as appropriate quantization methods to reduce the amount of feedback data are investigated. We also present a new power allocation algorithm in conjunction with adaptive modulation.