Type II port selection codebook

5G NR
1

What is the difference between Type II Codebook and Type II port selection codebook? Where are these codebooks used?

2

This can help you to understand:

What is a codebook and it’s relation to PMI?

  • Precoding

    • Precoding is a digital signal processing technique used to improve the performance of the communication system.
    • It involves the multiplication of the transmit signal by a precoding matrix, which is selected from the codebook.
    • The precoding matrix is chosen based on the channel state information (CSI) available at the transmitter.
    • This information is typically obtained through a feedback mechanism from the receiver (PMI).

  • Codebook in 5G

    • A codebook is a predefined set of complex valued matrices that represent various spatial precoding weights.
    • These weights are applied to the transmitted signals to improve the performance of the wireless link.
    • The codebook is designed based on certain criteria, such as maximizing the SNR at the receiver or minimizing the interference to other users in the network.
    • The codebook is indexed, and the index of the selected precoding matrix is fed back to the transmitter by the receiver using PMI.
    • When a receiver selects the most suitable precoding matrix from a codebook based on the current CSI, it sends the PMI back to the transmitter.
    • The transmitter then applies the corresponding precoding weights to the transmitted signals.
    • This process helps to focus the transmitted energy towards the desired receiver (beamforming), thus improving the signal quality and mitigating interference.

  • Codebook Types in 5G

    • Type I - Single Panel
    • Type I - Multi Panel
    • Type II - Single Panel
    • Type II - Port Selection

Credits: :point_down: