干扰约束下的认知无线电传输链路自适应算法

Transmission link adaptive algorithm based on interference constraint in cognitive radios

针对干扰约束下的认知无线电传输链路自适应算法开展研究,基于OFDM的认知用户与主用户共存,认知用户在保证对主用户干扰容限的前提下执行子载波与功率分配,以树形分支贪婪算法为基础,引入功率余量因子和干扰余量因子并通过比较余量因子相对大小来选择子载波,通过减小分支数以降低算法复杂度。仿真结果表明,改进的树形分支贪婪算法获得的系统容量与最优分配算法基本一致,但复杂度明显降低。

The paper aims to research the link adaptive algorithm under interference constraint in cognitive radios. Under the situation of coexistence between cognitive users and primary users based on OFDM technology, cognitive users execute subcarriers and power allocation on the premise of primary user interference tolerance. Based on the tree branch greedy algorithm, the paper brings in two parameters which are interference allowance factor and power allowance factor. The subcarriers are chosen by compar- ing the two parameters, and the algorithm complexity is reduced by decreasing the number of branches. The simulation shows that the improved tree branch greedy algorithm acquires almost the same system capacity with the optimal allocation algorithm, and the complexity of the algorithm is obviously reduced.