一种无线OFDM系统中的高效功率和比特分配算法
doi: 10.3724/SP.J.1146.2005.01149
A Computationally Efficient Transmit Power and Bit Allocations Algorithm for Wireless OFDM Systems
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摘要: 在限定无线OFDM通信系统的传输速率和最大误码率的情况下，该文提出了一种最小化发射功率的高效功率和比特分配算法。该算法首先利用注水水平和系统传输速率之间的关系求出无需预设步长和初始值的注水水平迭代公式，然后在部分子载波上使用简化的Greedy算法进行强制收敛。由于充分地利用了注水算法和Greedy算法的优点，该文算法不仅有效地避免了传统自适应算法的收敛性、初始值和步长选择等问题，而且计算效率更高。仿真结果验证了该算法的有效性。
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关键词:
- OFDM功率和比特分配注水算法
Abstract: In this paper, a computationally efficient algorithm for transmit power and bit allocations in wireless OFDM communication system is proposed, the aim is to minimize total transmit power under the constraints of data rate and max Bit Error Rate (BER). By exploiting the relation between water-filling level and system data rate, the proposed algorithm finds out an iterative method of searching water-filling level without preset step and initial value, then allocates the final bits and power with a simplified Greedy algorithm in partial subcarriers. The proposed algorithm avoids the probolems of the convergency probobality, the preset initial valuse and the selecting of optimal step in traditional adaptive water-filling algorithm by combining the water-filling and the Greedy algorithms effectivly, and its computationally efficiency is high. Simulation results verify the performance of the proposed algorithm. -
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