Power Efficient Dynamic Bandwidth Allocation Algorithm in OFDMA-PONs

Abstract—We propose two dynamic bandwidth alloca-tion (DBA) algorithms by considering three dimensions, i.e., time slot, subcarrier, and bit allocation, to minimize the transmitting power of optical network units (ONUs) in orthogonal frequency division multiplexing access passive optical networks (OFDMA-PONs). In the first proposed al-gorithm, we make use of the three-dimensional DBA algo-rithm from wireless OFDM, modify it according to the characteristics of the fiber channel, and apply it to up-stream access in OFDMA-PONs to reduce the transmitting power of ONUs. In order to furtherminimize the total trans-mitting power, we propose the second algorithm by allocat-ing the subcarrier and bit in the same procedure. The complexity of the two proposed algorithms was evaluated by polynomial time. From simulation results, the transmit-ting power of ONUs under a certain bit error rate is re-duced by ∼30 % and ∼50 % using the first and the second proposed algorithms, respectively, compared with the traditional two-dimensional DBA algorithm in OFDMA-PONs. Index Terms—Dynamic bandwidth allocation; Orthogonal frequency multiplexing access passive optical networks