Uplink detection method and device in non-orthogonal multiple access system, and base station

A base station, comprising a processor, a transceiver and a memory, wherein

• the processor is configured to read programs in the memory so as to:
• perform pilot activation detection on each terminal in a first terminal set corresponding to an non-orthogonal multiple access (NOMA) transmission unit block repeatedly until a detection end condition is met, wherein the first terminal set comprises terminals that may transmit uplink data on the NOMA transmission unit block,
• perform, on a time-frequency resource of the NOMA transmission unit block, channel estimation on each terminal in a second terminal set determined through the pilot activation detection within each repetition period, wherein the second terminal set comprises terminals that have actually transmitted the uplink data on the NOMA transmission unit block, and
• detect and decode a data channel according to a channel estimation result of each terminal in the second terminal set within each repetition period and an uplink data signal on the time-frequency resource of the NOMA transmission unit block;
• the transceiver is configured to receive and transmit data under the control of the processor;
• and
• the memory is configured to store therein data for the operation of the processor;
• wherein in the case that the pilot activation detection is performed on each terminal in the first terminal set corresponding to the NOMA transmission unit block, the processor is further configured to read the programs in the memory, so as to:
• perform, based on a pilot signal received power or a pilot-signal correlation, the pilot activation detection on each terminal in the first terminal set corresponding to the NOMA transmission unit block;
• wherein in the case that the pilot activation detection is performed on each terminal in the first terminal set corresponding to the NOMA transmission unit block, the processor is configured to read the programs in the memory, so as to:
• perform least squares LS channel estimation on a pilot signal on the NOMA transmission unit block in a frequency domain, to obtain a frequency domain LS channel estimation value;
• convert the frequency domain LS channel estimation value to a time domain channel estimation value;
• determine a detection statistic value and a judgment threshold of interference noise power according to the time domain channel estimation value;
• and determine the second terminal set according to the detection statistic value and the judgment threshold of the interference noise power;
• or
• determine an autocorrelation matrix of a pilot signal on each uplink subcarrier of the time-frequency resource of the NOMA transmission unit block;
• determine an average value of autocorrelation matrices of pilot signals on all uplink subcarriers of the time-frequency resource of the NOMA transmission unit block;
• determine a maximum eigenvalue and a minimum eigenvalue of the average value;
• and determine the second terminal set according to the maximum eigenvalue and the minimum eigenvalue.