Precoding matrix

1. What is precoding matrix?
2. What is precoding matrix indicator in 5G?
3. What is precoding and beamforming?
4. Why precoding is used in MIMO?

What is precoding matrix?

Precoding is a technique that exploits transmit diversity by weighting the information stream, i.e. the transmitter sends the coded information to the receiver to achieve pre-knowledge of the channel. The receiver is a simple detector, such as a matched filter, and does not have to know the channel state information.

What is precoding matrix indicator in 5G?

This is a E-UTRA parameter related to MIMO feedback for some of the E-UTRA transmission modes. The precoding feedback is used for channel dependent codebook based precoding and relies on UEs reporting the desired PMI (Precoding Matrix Indicator).

What is precoding and beamforming?

The term precoding refers more to a software implementation of communication theory, and beamforming refers more to the hardware implementation and the antennas in the system. And precoding generally refers to the transmitter side, while beamforming can be applied to both transmitters and receivers.

Why precoding is used in MIMO?

Precoding is a process used at the transmitter end to weight the information stream depending on the CSI [5]. Precoding helps in shifting the hardware complexity to the base station from the transmitting mobile station. In MIMO systems, to achieve better system performance, the information of complete CSI is required.