Efficient Capacity-Based Joint Quantized Precoding and Transmit Antenna Selection Using Cross-Entropy Method for Multiuser MIMO Systems

Table 1

Complexity of joint precoding and transmit antenna selection algorithms where 𝑛_𝑇 is the number of selected transmit antennas, 𝑁_𝑇 is the number of total antennas, 𝐾 donates the number of users, 𝐿 donates the number of feedback bits, 𝑁_GA and 𝜏_GA are the population size and iterations used in the GA algorithm, and 𝑁_CE and 𝜏_CE are the population size and iterations used in the CE method.

Algorithms	Complexity order 𝒪	(𝑁𝑇,𝑛𝑇,𝐾,𝐿)=(16,4,2,6)
Exhaustive search method	𝒪(𝐶^𝑁𝑇𝑛𝑇×𝑃^2𝐿𝐾)	7,338,240
GA method	𝒪(𝑁GA×𝜏GA)	16,800
CE method	𝒪(𝑁CE×𝜏CE)	16,800