Photodetector triggered pulse selection from a mode locked ruby laser
Photodetector triggered single pulse selection from mode locked ruby laser
Billman, K. W.↗
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Random walk techniques in the solution of first order digital phase-locked loops
First order digital phase locked loops analysis for single channel command system, using random walk techniques
Holmes, J. K.↗
Frequency-counted measurements and phase locking to noisy oscillators
Frequency counted measurements and phase locking to noisy oscillators, showing counted frequency method sample variance slow convergence to actual variance
Gray, R. M.↗
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.↗
An all digital phase locked loop for FM demodulation
Digital phase locked loop for FM signals demodulation, considering system nonlinear difference equation
Garodnick, J.↗
The approximate transient performance of a phase-locked loop on board a tumbling satellite
Transient performance of phase locked loop onboard tumbling satellite, noting relation to time, SNR and fade modulation
Yao, K.↗
Mode locking of the CW dye laser
CW dye laser mode locking with lithium niobate phase modulator, observing 500 psec pulse generation
Kuizenga, D. J.↗
A compilation of results pertaining to the behavior of phase locked loops
State-of-the art on phase locked loops PLL is reported by summarizing some specific results. Following a statement of the overall analysis and design objectives, results are presented in a format identifying working terminology, inherent assumptions, and references for each result. The use of PLL in tracking, synchronization, and demodulation is reemphasized, as well as the mathematical challenge involved in solving nonlinear stochastic differential equations.
Gleicher, N.↗
Phase-lock demodulation of a PM signal contaminated with incidental AM
Signals from phase-modulated satellite transmitters usually exhibit some degree of incidental amplitude modulation. The effects of incidental AM are analyzed when this type of signal is demodulated by a phase-lock receiver which does not employ a limiter preceding the loop phase detector. The presence of incidental AM causes a reduction in the receiver output signal-to-noise ratio. The tolerable level of AM decreases in proportion to the phase modulation index Beta. For a square-wave modulating signal, a 1 db reduction results at the receiver PM channel output when Beta = 1 radian and the percentage of AM = 23, Beta = 1.2 radians and the percentage of AM = 16, or Beta = 1.5 radians and the percentage of AM = 4. Although only the PM channel of the receiver is used ordinarily, utilizing both the AM and PM channel by summing offers an improvement in S/N relative to the S/N ratio of the PM channel if the percentage of incidental AM is greater than fifteen.
Robinson, G. B.↗
Acquisition time for sideband modulated phase lock loops.
In this paper a definition for acquisition of a sideband modulated carrier is proposed for the phase lock loop, and the acquisition differential equation solved for a region of the modulation parameter space to determine the expected value of acquisition time. Principally the case of modulation by a single unmodulated subcarrier is considered. The numerical analysis is made for the noiseless case.
Gilbert, A. L.↗
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.↗
Effect of saturated frequency chirping on mode-locked laser pulses.
A dye-induced nonlinear frequency chirping is analytically shown to have significant modifications on the nature of the output mode-locked lasers. It is shown that the saturated frequency sweeping is responsible for substantial pulse broadening as well as substructures.
Kim, D. M.↗
The digital phase-locked loop as a near-optimum FM demodulator.
This paper presents an approach to the optimum digital demodulation of a continuous-time FM signal using stochastic estimation theory. The primary result is a digital phase-locked loop realization possessing performance characteristics that approach those of the analog counterpart. Some practical considerations are presented and simulation results for a first-order message model are presented.
Kelly, C. N.↗
Near optimum digital phase locked loops.
Near optimum digital phase locked loops are derived utilizing nonlinear estimation theory. Nonlinear approximations are employed to yield realizable loop structures. Baseband equivalent loop gains are derived which under high signal to noise ratio conditions may be calculated off-line. Additional simplifications are made which permit the application of the Kalman filter algorithms to determine the optimum loop filter. Performance is evaluated by a theoretical analysis and by simulation. Theoretical and simulated results are discussed and a comparison to analog results is made.
Polk, D. R.↗
An all digital phase locked loop for FM demodulation.
A phase-locked loop designed with all-digital circuitry which avoids certain problems, and a digital voltage controlled oscillator algorithm are described. The system operates synchronously and performs all required digital calculations within one sampling period, thereby performing as a real-time special-purpose computer. The SNR ratio is computed for frequency offsets and sinusoidal modulation, and experimental results verify the theoretical calculations.
Greco, J.↗
Automatic carrier acquisition system for phase-lock-loop receivers
Programmable oscillator and zero-beat detector acquires phase-lock of carrier by frequency scanning. Generation of high-level dc pulse at instant of zero crossing provides positive trigger for decision gate to stop search and close loop for phase-coherent tracking.
Bunce, R. C.↗
Frequency control circuit for all-digital phase-lock loops
Phase-lock loop references all its operations to fixed high-frequency service clock operating at highest speed which digital circuits permit. Wide-range control circuit provides linear control of frequency of reference signal. It requires only two counters in combination with control circuit consisting only of flip-flop and gate.
Anderson, T. O.↗