Types of beamforming in 5G

There are 3 types of beamforming used in 5G:

• Analog Beamforming: same signal is fed to each antenna and then analog phase-shifters are used to steer the signal emitted by the array so beams are controlled by a series of phase-shifters to send the same signal from multiple antennas but with different phases
• Digital Beamforming: designs different signals for each antennas in the digital baseband. There is RF CHAIN for each antenna This makes digital beamforming particularly desirable for spatial multiplexing, where we want to transmit a superposition of signals, each with a separate directivity.
• Hybrid Beamforming: combines the digital beamforming and analog beamforming, it means part of the beamforming is done by digital processing in the baseband, and part of the beamforming by analog RF beamformers. The number of TRXs and RF Chains in the beamforming antenna are in general lower than the number of antennas.