多带OFDM-UWB动态子载波分配算法

Dynamic subcarrier allocating algorithm for multi-band OFDM-UWB system

超宽带系统的传输功率谱密度是严格限制的,发射功率是超宽带系统的主要性能指标之一。为了最小化系统总发射功率,论文在给定用户速率和误比特率限制的前提下提出了一种新的功率最小化的自适应子载波分配算法。该算法采用次优算法,通过基于差值的子载波选择、子载波比特分配和相同比特子载波分配优化三个完整的动态分配,有效避免了衰落严重的子载波对用户传输性能的影响。仿真结果表明,在没有增加算法复杂度的情况下该算法的单位比特功耗和误比特率性能要优于其它算法1dB以上。

The power spectral density of ultra-wideband system is strictly limited,and the transmission power is one of the main performances to be taken into consideration.In this paper,a new adaptive subcarrier allocating algorithm is proposed for multiuser multiband orthogonal frequency division multiplexing ultra-wideband system.This algorithm dynamically assigns the subcarriers and bits for multiuser to minimize the total transmission power for a given bit error rate and user＇s data rate.It avoids the effect of deep fading subcarriers on the user effectively by perfectly dynamical allocating subcarriers,which is sub-optimal and includes subcarrier selecting based difference,bit allocating and subcarrier optimizing between users with the same bits.Simulation results show that the algorithm has more than 1 dB gain over other algorithms in power per bit and bit error rate under the same complexity.