认知无线电中差值能量检测

在认知无线电系统中，认知用户需要实时准确地判断频谱的使用情况。研究了能量检测算法的检测性能，发现当噪声波动性较大时，能量检测性能会大幅下降，在低信噪比时尤为明显。因此提出利用噪声不确定性的最大波动范围修正能量检测，并在此基础上提出了一种差值联合能量检测，即通过每次能量检测的差值变化大小校正判决结果，得到最终的融合判决结果。仿真表明，这种改进的能量检测方法的性能在保证传统能量检测优点的情况下有效地提高了认知用户对频谱实时准确的检测性能。

Difference Value Energy Detection in Cognitive Radio

In cognitive radio systems, cognitive users need to accurate determine the using of the spectrum by real-time.Studying the performance detection of energy detection, it was found that the larger the noise fluctuations, the sharper the decline in performance of energy detection, especially in low SNR. We used the maximum fluctuations range of the noise uncertainty to amend the energy detection and gave a joint detection of the difference value and the energy which utilize the alteration of the difference value in the every energy detection to amend the judgment result and get the blending final result based on it. Simulation results show that under guaranteeing the advantage of the traditional energy detection the performance of our new energy detection can effectively improve the cognitive users accurate detection per-formance of spectrum usage in real-time.