SRS antenna round hair
As we all know, 5G networks and others support beaforming technology, which can be directed to the terminal. If the base station wants to transmit directionally, it must first detect the location of the terminal, the quality of the transmission path, etc., so that the resources of the base station are more accurately allocated to each terminal. Sending SRS information by the terminal is one of the methods used by the base station to detect the terminal location and channel quality (the other is the PMI method, which will not be expanded for the time being).
SRS stands for Sounding Reference Signal (SRS). SRS round transmission refers to which physical antenna the terminal sends SRS information on.
In SRS mode, the more antennas that can participate in the transmission of reference signals, the more accurate the channel estimation, and the higher the rate that can be obtained; if only the fixed antenna is sent, other antenna information will be lost, and the antenna is not fully utilized and difficult to obtain The highest rate.
5G terminals are generally equipped with multiple transceiver antennas. At present, mainstream 5G mobile phones and CPEs use 2 transmitting antennas and 4 receiving antennas (that is, 2T4R). If multiple antennas of 5G terminals are used to report channel information in turn (that is, SRS antennas transmit in turn), the information obtained by the base station can be more comprehensive and more accurate data transmission can be performed:
In 1T1R, only one antenna is fixed to feed back SRS information to the base station, that is, SRS round transmission is not supported.
In 1T4R, the terminal transmits SRS signals on 4 antennas in turn, and selects 1 antenna for transmission at a time; NSA terminals often use this mode.
2T4R, the terminal transmits SRS signals on 4 antennas in turn, and selects 2 antennas to transmit at a time; SA terminals often use this mode.
Others include 1T2R, etc., and so on. (Note: R here means round-turn, not receive-receive)
