MIMO receiver that selects candidate vector set and operation method thereof

An operation method, performed by a receiver, of receiving at least first and second transmit signals through a plurality of antennas, the operation method comprising:

• calculating, with respect to the first transmit signal, Euclidean distances with respect to all of candidate vectors of an initial candidate vector set;
• selecting a first candidate vector set from among a plurality of candidate vector sets, based on information about the Euclidean distances, each size of the plurality of candidate vector sets being different;
• and
• generating a log likelihood ratio (LLR) with respect to symbols of the second transmit signal based on the first candidate vector set.

A method, performed by a receiver, of detecting signals in a wireless communication system comprising a multiple input multiple output (MIMO) channel, the method comprising:

• calculating, for each physical channel of the MIMO channel, information based on one or more of received transmit signals and predetermined candidate vectors, and generating, based on the information, a log likelihood ratio (LLR) with respect to the one or more of the received transmit signals;
• selecting, based on the information, a first candidate vector set from among a plurality of candidate vector sets having different sizes for generating the LLR;
• and
• generating an LLR with respect to received transmit signals received subsequently to the one or more of the received transmit signals based on the first candidate vector set.