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24 result(s) found where the letter starting with "P"

Package
A definition of the style of enclosure in which the oscillator will be packaged. This may be done by drawing or may be selected from a set of standard packages. The package includes all dimensions and connection definitions.
 

Parts per million
A measure of frequency compared to the center frequency of the oscillator. It is defined as one Hertz per Megahertz of the oscillator frequency.A measure of frequency compared to the center frequency of the oscillator. It is defined as one Hertz per Megahertz of the oscillator frequency.
 

PBX
Private Branch Exchange
 

PCM
Pulse Code Modulation
 

PCS
Personal Communications Services
 

PDH
Plesiochronous Digital Hierarchy
 

PDOP
Position Dilution of Precision
 

Period
The time required for one repetition (cycle) of the output waveform measured in seconds or fractions of seconds. It is mathematically identical to the inverse of frequency (1/frequency).
 

Phase
A measure of a fraction of the period of a repetitive phenomenon, measured with respect to some distinguishable feature of the phenomenon itself. In the standard frequency and time signal service, phase time differences such as time differences between two identified phases of the same phenomenon or of two different phenomena are mainly considered.
 

Phase deviation
The difference of the phase from a reference.
 

Phase jump
A sudden phase change in a signal.
 

Phase locked loop
A circuit in which a crystal oscillator is used as a time base for a voltage controlled oscillator maintaining frequency and phase lock between the two oscillators. This is a useful technique for achieving a frequency programmable crystal oscillator and output frequencies that are out of the range of a crystal manufactured to achieve certain performance specifications. However, short term frequency stability is one or two orders of magnitude worse than for a true crystal oscillator.
 

Phase noise
In an oscillator, rapid, short-term, random fluctuations in the phase of a wave, caused by time-domain instabilities. Note: Phase noise, in decibels relative to carrier power (dBc) on a 1-Hz bandwidth, is given by = 10log[0.5(S (f ))] where S (f ) is the spectral density of phase fluctuations.
 

Phase shift
An intentional change in phase from a reference.
 

Phase signature
A deliberate phase offset for the purpose of signal identification. For example, NIST's radio station WWVB broadcast is deliberately phase shifted at 10 minutes after the hour, so a person knows that WWVB is being tracked and not some other signal.
 

PLL
See phase locked loop.
 

ppm
See parts per million.
 

PPS
Pulse Per Second.
 

Precision
The degree of mutual agreement among a series of individual measurements. Precision is often, but not necessarily, expressed by the standard deviation of the measurements.
 

Primary Server
Another name for a stratum 1 server. See also "stratum".
 

PRN
Pseudo/Random Noise Code.
 

PRR
Primary Reference Receiver.
 

PRS
Primary Reference Source.
 

PSTN
Public Switched Telephone Network.