A Semidynamic Bidirectional Clustering Algorithm for Downlink Cell-Free Massive Distributed Antenna System

Algorithm 1

Semidynamic Bidirectional Clustering Algorithm.

Initialization: RAPs set , MSs set , cluster set , . MSs set .

Step 1: associate MSs with their respective RAP according to the maximum large-scale fading.

 for do

  , for .

 end for

Step 2: calculate the average rate gain per MS of cooperation cluster between any two clusters.

 for do

  for do

   calculate and based on (19),

  end for

 end for

Step 3: merge cooperation cluster.

 while do

  if then

   update and , , , , , , go to step 2.

  end if

  if then

   update , go to step 3.

  end if

 end while