Adaptive MU-MIMO beamforming

A base station (BS) for wireless communication comprising

• an electromagnetic lens (EML) that produces different phase factors to uplink (UL) incident waves from the same direction;
• M antennas that receive and/or transmit signals that pass through the EML wherein the angles of arrival and/or departure of one or more User Equipment (UE) are mapped to a subset of m antennas with m≤M;
• N (N≤M) radio frequency (RF) paths for transmitting and/or receiving;
• a connection and switch network that maps the signals from the M antennas to the N RF paths in the uplink (UL) or maps the signals from the N RF path to the M antennas in the downlink (DL);
• and,
• a processor unit that measures or estimates a receiving signal strength (RSS), Signal-to-Noise Ratio (SNR) or similar metrics on each antenna for each User Equipment (UE) based on one or more received UL reference signals, and generates signal(s) to control the connection and switch network to map the signals from the N RF paths to the M antennas and/or to control the connection and switch network to map the signals from the M antennas to the N RF paths,
• wherein the RF path selection to map the signals from the M antennas to the N RF paths in the UL or to map the signals from the N RF path to the M antennas in the DL are predefined for Customer Premise Equipment (CPEs) in fixed wireless access wherein each pre-defined RF path selection produces a pattern of beams serving a subset of CPEs, the BS serves the CPEs using Time Division Multiple Access (TDMA) by selecting a RF path selection to serve a subset of CPEs in a given time slot.

A method for wireless communication comprising one or more user equipment (UE) transmitting one or more uplink (UL) reference signals in a time slot allocated by a base station (BS);

• the BS controlling a connection and switch network to switch to a UL signal reception mode;
• the BS measuring and estimating on each of its M antennas the received signal strength (RSS), Signal-to-Noise Ratio (SNR) or similar metrics based on the received UL reference signals from each UE;
• the BS determining the connections to connect which of the M antennas to which of N RFs where M≥N and which antennas and/or which RF paths are to be turned off in a following data transmission time slot based on the scheduled UEs and the associated estimate of the RSS, SNR or similar metrics of the received UL reference signal from each of the scheduled UEs on each antenna;
• and the BS controlling the connection and switch network to implement the connections and to switch to a data transmission/reception mode.