提出了一种I支路功率方差比方法(I branch power variance ratio,IBPVR),并详细推导了另外3种载噪比估计方法(NWPR、MM、SNV),比较了这4种方法在强信号和弱信号情况下的跟踪性能。实验结果显示,在载噪比超过50dBHz时,NWPR方法与SNV方法并未出现饱和现象,SNV方法在弱信号情况下会产生估计偏差,NWPR与IBPVR方法的估计性能比较好。 An I branch power variance ratio (IBPVR) method was proposed and three other methods of estimating carrier to noise ratio (NWPR, MM, SNV) were deduced in detail. Compared these four methods, And weak signal tracking performance. Experimental results show that there is no saturation phenomenon between NWPR method and SNV method when the carrier-noise ratio exceeds 50dBHz, and the SNV method produces estimation error in the case of weak signal, and the estimation performance of NWPR and IBPVR methods is good.