A New Hybrid Protocol for Random Access and Data Transmission Based on Two-Phase ACB Mechanisms for M2M Communications

Algorithm 1

Joint optimization of the ACB factors and the number of RBs for PRACH.

Input:

The total number of RBs in a RA cycle (i.e., ), the estimated number of active M2M UEs in the th cycle (i.e., ), the number

of preambles assigned in every 6 RBs in the th cycle (i.e., ), the number of RBs constituting one PUSCH in the th cycle (i.e., ).

Output:

The first ACB factor (i.e., ), the second ACB factor (i.e., ), the number of RBs for PRACH (i.e., ).

()if    then

()Determine the first ACB factor .

()Determine the number of RBs for PRACH based on (22) and (23).

()Determine the second ACB factor .

()else

()Determine the first ACB factor .

()Determine the number of RBs for PRACH based on (19) and (20).

()Determine the second ACB factor .

()end if

() return  , , ;