Phase-locked Loop Dynamics in the Presence of Noise by Fokker-planck Techniques
Phase error behavior of phase-locked loop tracking system in presence of gaussian noise determined by fokker-planck equation
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Tracking analysis of a first order phase- locked loop with two sinewaves modulation
Phase locked-loop tracking with sine wave modulation in Apollo communication systems
Lee, S. Y.↗
A class of optimum digital phase locked loops
This paper presents a class of optimum digital filters for digital phase locked loops, for the important case in which the maximum update rate of the loop filter and numerically controlled oscillator (NCO) is limited. This case is typical when the loop filter is implemented in a microprocessor. In these situations, pure delay is encountered in the loop transfer function and thus the stability and gain margin of the loop are of crucial interest. The optimum filters designed for such situations are evaluated in terms of their gain margin for stability, dynamic error, and steady-state error performance. For situations involving considerably high phase dynamics an adaptive and programmable implementation is also proposed to obtain an overall optimum strategy.
Kumar, R.↗
Threshold analysis of phase-locked-loop demodulators using most likely noise
Threshold carrier to noise ratio for phase lock demodulators, using computerized prediction model
Osborne, P. W.↗
First slip times versus static phase error offset for the first- and passive second-order phase-locked loop
Slip vs static error offset for first and passive second order phase locked loop as function of signal to noise ratio via computer simulation
Holmes, J. K.↗
Phase-locked injection laser arrays with nonuniform stripe spacing
A new type of phase-locked injection laser array which utilises nonuniform spacing between the lasing stripes has been studied. The variation in spacing alters the stripe-to-stripe coupling which modifies the array mode selection. Arrays that operate with a single far-field lobe have been fabricated.
Ackley, D. E.↗
Application of multirate digital filter banks to wideband all-digital phase-locked loops design
A new class of architecture for all-digital phase-locked loops (DPLL's) is presented in this article. These architectures, referred to as parallel DPLL (PDPLL), employ multirate digital filter banks (DFB's) to track signals with a lower processing rate than the Nyquist rate, without reducing the input (Nyquist) bandwidth. The PDPLL basically trades complexity for hardware-processing speed by introducing parallel processing in the receiver. It is demonstrated here that the DPLL performance is identical to that of a PDPLL for both steady-state and transient behavior. A test signal with a time-varying Doppler characteristic is used to compare the performance of both the DPLL and the PDPLL.
Sadr, R.↗
Application of multirate digital filter banks to wideband all-digital phase-locked loops design
A new class of architecture for all-digital phase-locked loops (DPLL's) is presented in this article. These architectures, referred to as parallel DPLL (PDPLL), employ multirate digital filter banks (DFB's) to track signals with a lower processing rate than the Nyquist rate, without reducing the input (Nyquist) bandwidth. The PDPLL basically trades complexity for hardware-processing speed by introducing parallel processing in the receiver. It is demonstrated here that the DPLL performance is identical to that of a PDPLL for both steady-state and transient behavior. A test signal with a time-varying Doppler characteristic is used to compare the performance of both the DPLL and the PDPLL.
Sadr, Ramin↗
Carrier arraying with coupled phase-locked loops for tracking improvement
This paper considers a system that couples several phase-locked loops (PLL's) to improve carrier tracking performance. The system coherently combines the received carrier signals at geographically separated ground antennas to increase the total effective aperture. It automatically aligns the received carrier's phases to enhance received carrier signal-to-noise ratio. The tracking performance of this system is being assessed in terms of rms phase jitter.
Divsalar, D.↗
Phase-Locked Loop For Measurement Of Small And Large Delays
Electronic signal-generating and processing subsystem of ultrasonic inspection or measurement system consists mainly of variable-and-fixed-frequency, pulsed phase-locked loop (VFFPPLL) measuring phase shifts from 0 degrees to more than 360 degrees with accurancy of 0.112 degrees. VFFPPLL measures phase shifts between transmitted ultrasonic toneburst and its echo, thereby measuring ultrasonic-propagation delay. Used to determine strain in bolt or to track irregular surface of specimen being inspected ultrasonically.
Froggatt, Mark↗
A class of optimum digital phase locked loops for the DSN advanced receiver
A class of optimum digital filters for digital phase locked loop of the deep space network advanced receiver is discussed. The filter minimizes a weighted combination of the variance of the random component of the phase error and the sum square of the deterministic dynamic component of phase error at the output of the numerically controlled oscillator (NCO). By varying the weighting coefficient over a suitable range of values, a wide set of filters are obtained such that, for any specified value of the equivalent loop-noise bandwidth, there corresponds a unique filter in this class. This filter thus has the property of having the best transient response over all possible filters of the same bandwidth and type. The optimum filters are also evaluated in terms of their gain margin for stability and their steady-state error performance.
Hurd, W. J.↗
Designing Estimator/Predictor Digital Phase-Locked Loops
Signal delays in equipment compensated automatically. New approach to design of digital phase-locked loop (DPLL) incorporates concepts from estimation theory and involves decomposition of closed-loop transfer function into estimator and predictor. Estimator provides recursive estimates of phase, frequency, and higher order derivatives of phase with respect to time, while predictor compensates for delay, called "transport lag," caused by PLL equipment and by DPLL computations.
Statman, J. I.↗
External cavity coupling and phase locking of gallium arsenide injection lasers.
Gallium arsenide injection lasers, discussing external cavity coupling, phase locking, laser uniformity, dimensions and arrays
Ahearn, W. E.↗
The non-linear transient behavior of second, third and fourth order phase-locked loops
Non-linear transient behavior of second, third, and fourth order phase-locked loops
Carden, F. F.↗
Time to cycle slip in first and second order phase lock loops
Markov process for time to cycle slip in first and second order phase lock loops
Schuchman, L.↗
Optimal signal-to-noise in digital phase lock amplifiers
An expression for the optimal signal-to-noise ratio for linear phase lock amplifiers is derived. In its digital form the optimal method can be implemented by real-time signal processing techniques. The case of detector-noise-limited systems is analyzed in detail; it is found that the optimal technique can be used to eliminate effectively the detector's time constant from the set of parameters determining the overall efficiency. This has important implications for optical detection system design. Also reported is an experimental verification of the optimal method, thus establishing its practicality.
Doering, Charles R.↗
Automatic frequency discriminators and control for a phase-lock loop providing frequency preset capabilities Patent
Development of automatic frequency discriminators and control for phase lock loop providing frequency preset capabilities
Kline, A. J., Jr.↗
On the probability of cycle-slipping in first-order phase-locked loops.
The first-passage time boundary value problem for first-order phase-locked loops (PLL) is analyzed, and spectral representations are developed for the probability density function (pdf), the distribution function, and the moments of the first time to passage (or cycle-slip). For the sinusoidal PLL, an asymptotic formula, that is surprisingly accurate even at low loop SNR's and large frequency offsets, is obtained for the pdf of the time to cycle-slip, in terms of the mean time to slip.
La Frieda, J. R.↗