Research on an Improved Power Allocation Algorithm in OFDM-based Cognitive Radio Systems
Xuezhi Tan · Science Technology and Engineering · 2011
The iterative partitioned water-filling algorithm is improved applying in the power allocation in the OFDM-based cognitive radio systems that aimed at maximizing the capacity of the systems with the consideration of the total power constraint and each subchannel power constraints.The power leakage of the adjacent subcarriers is especially considered when the power constraints of the PU s are very strict,and set the protection band between the PU s' spectrum and the SU s' spectrum and made power allocation of the other subcarriers form the ladder shape,only performing the iterative partitioned water-filling algorithm in the subchannels whose power constraints were strict.The simulation result shows that the improved power allocation algorithm is not only close to the iterative partitioned water-filling algorithm,but also has low complexity.