Citation
Abstract
Two possible algorithms for the carrier-to-noise power (P./No) estimation in the Block V Receiver are analyzed and their performances compared. The expected value and the variance of each estimator algorithm are derived. The two algorithms examined here are known as the I-arm estimator, which relies on samples from only the in-phase arm of the digital phase-lock loop, and the IQ-arm estimator, which uses both in-phase and quadrature-phase arm signals. The IQ-arm algorithm is currently implemented in the Advanced Receiver II (ARX II). Both estimators are biased. The performance degradation due to phase Jitter in the carrier tracking loop is taken into account. Curves of the expected value and the signal-to-noise ratio of the P./Ng estimators versus actual P,/No are shown. From this, it is clear that the Earm estimator performs better than the IQ-arm estimator when the datato-noise power ratio (Pa/No) is high, 1.e., at high P./No values and a significant modulation index. same performance. When Py/No is low, the two estimators have essentially the rate of I; and Q; is f;/K = 1/T,, where T, = KT; is
Details
- Volume
- 42-106
- Published
- August 15, 1991
- Pages
- 353–363
- File Size
- 338.2 KB