Low-Complexity User Selection for Rate Maximization in MIMO Broadcast Channels with Downlink Beamforming

Algorithm 1

Iterative power projection (IPP).

(1)  Ω={1,…,𝐾}, 𝒮=∅, 𝑛=0

(2)  while  |𝒮|<𝑁_𝑡  do

(3)  if  𝑛=0  then

(4)  Compute 𝑖^∗ by (16)

(5)  else

(6)  Compute 𝑖^∗ by (22)

(7)  end  if

(8)  𝑛=𝑛+1, 𝒮(𝑛)=𝒮(𝑛−1)∪{𝑖^∗}, Ω(𝑛)=Ω(𝑛−1)−{𝑖^∗}

(9)  Update Ω(𝑛) by (25)

(10)  end  while

(11)  Power Loading Principle: water-filling