Unlock instant, AI-driven research and patent intelligence for your innovation.

PLL for reproducing standard clock from random time information

A standard clock and random time technology, applied in the field of digital PLL, can solve problems such as unstable fluctuation suppression characteristics

Inactive Publication Date: 2004-02-04
NEC CORP
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, when the sampling interval is random, the fluctuation suppression characteristics of the system will be unstable due to the jitter of each delay time and the jitter of the time constant of the delay element due to the dispersion of the arrival time of the digital signal

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • PLL for reproducing standard clock from random time information
  • PLL for reproducing standard clock from random time information
  • PLL for reproducing standard clock from random time information

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0049] Reference embodiments of the present invention will be described below with reference to the accompanying drawings.

[0050] Such as figure 1 As shown, the second type of PLL according to the first embodiment of the present invention is a standard clock transmission system. At the sender, the count value of the standard clock is read at a random time interval smaller than the time interval T, and the sender The resulting time signal is transmitted. The PLL device includes: a receiving counter 4-1 having the same structure as the sending side counter, for counting the standard clock received by the receiving side; a memory 4-2 for storing the output of the receiving counter at a predetermined stage; a subtractor 4 -3, for comparing the count value of the reception counter 4-1 with the count value received by reading the count value of the reception counter 4-1 every time the count value of the sender counter is transmitted; difference time calculator 4-4 is used to ca...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A PLL is provided for reproducing a standard clock having a constant Jitter band from a random time information. This PLL is composed of a receiving counter 4-1; a subtractor 4-3; a differential time calculator for calculating a difference between the present count value and the preceding count value of the receiving counter; a first attenuator 4-5; a second attenuator 4-6; an integrator 4-7 for integrating the output of the second attenuator based on the differential time calculated by the differential time calculator; an adder 4-8 for adding the outputs of the adder and the integrator; a converter 4-9; and a voltage control oscillator 4-10.

Description

technical field [0001] The present invention relates to a phase-locked loop circuit (abbreviated as PLL hereinafter) and in particular to a circuit for performing image processing in a system such as MPEG2 (Motion Picture Experts Group 2) which is larger than the current television system and which is received at the receiving side of a transmission system. The encoded standard clock recovers the standard clock from the digital PLL. Background technique [0002] According to the MPEG specification of ISO (International Organization for Standardization), the digital transmission system of dynamic images is still under study. The sender sends a digital signal that conforms to the count of the sending counter by reading the count at random time intervals. At the same time, the receiver The PLL recovers the standard clock synchronized with the sender clock based on the digital signal obtained, which is the difference obtained by comparing the sender digital signal with the count...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H04N5/06H03L7/08H03L7/181H04L7/033H04N5/04H04N5/12H04N19/00H04N19/70H04N19/80
CPCH03L7/181H04N5/126H04N5/04H04N5/4401H03L7/08H04N21/426H04N21/4305
Inventor 六郷义典
Owner NEC CORP