Hello everyone. Today I will bring you the RTN560A beamforming process. Hope it helps you.
This section describes the overall beamforming process.
The beamforming process consists of three steps:
Sector sweep (SLS): indicates the coarse scanning to determine the general orientation.
Fine-grained adjustment (BRP): Beam Refinement adjusts beams to the optimal receive beam.
Beam tracking (BT): Beam tracking, which keeps tracking and antenna alignment when the device is running at a low speed.
The following figure shows the beamforming process.
Beacon broadcast phase:
The RBS uses table lookup to obtain the preset wavelength code table during transmission, sends broadcasts in all directions, and the TAU receives broadcasts in all directions.
The TUA demodulates broadcast parameters to determine the broadcast period and data transmission time.
Sector sweeping phase:
Training and transmission are performed to find the best transmit beam.
The RBS/TAU listens to the channel and sends a request signal or a request signal to send a request signal to obtain a transmission opportunity.
The TAU obtains the preset wavelength code table by searching the table and transmits SSW frames in each direction. The SSW frames contain the MAC address of the RBS.
After receiving the scan request, the RBS transmits SSW frames in all directions.
The TAU notifies the RBS of the best beam direction in the SSW-Feedback message.
The RBS notifies the TAU of the best frame number in an SSW-ACK message.
Precise adjustment phase: Training transmit and receive signals, and generating a new receive wave code table using channel phase estimation.
The RBS/TAU uses dedicated BRP frames for two interactions to generate a receive wave code table.
The RBS/TAU uses the preset wave code table to transmit data and the newly generated wave code table to receive data. Both transmit data using directional beams, achieving beamforming.
