-
1.发明授权Apparatus and method for generating a horizontal reset signal synchronous with a subcarrier locked clock 失效用于产生水平复位信号与SUBCARRIER锁定时钟同步的装置和方法
公开(公告)号：US5053862A
公开(公告)日：1991-10-01
申请号：US339032
申请日：1989-04-14
CPC分类号： H04N9/44
摘要： A method and apparatus for synchronizing a received television signal to a subcarrier locked signal is provided. The apparatus includes a comparison block for determining whether the received television signal and subcarrier locked signal are related by a predetermined fixed frequency relationship and for providing indications of the same, and a signal generation block for dividing down the subcarrier locked signal according to the predetermined fixed frequency relationship so as to provide an output signal which is synchronized with the subcarrier locked signal, and at a frequency determined according to the fixed frequency relationship when the signals are related. The apparatus is particularly useful in PIP applications where the received television signal is a horizontal signal and the subcarrier locked signal is a four times multiple of the subcarrier frequency. The comparison block preferably includes a counter and a windowing circuit for determining whether edges of horizontal signal pulses are received within or outside a predetermined time window, and a decision circuit for determining whether the occurrences (counts) of in and out of window edges are indicative of related or unrelated signals. The entire apparatus preferably includes only flip-flops, simple logic gates such as AND, NAND, or OR gates, inverters, multiplexer switches, and resettable counters. The apparatus also preferably further includes a standard combination of flip-flops and a NAND gate for providing a synchronized horizontal reset output signal when the comparison block determines that the received horizontal clock and the subcarrier locked clock are not related.
-
2.发明授权Apparatus and method for creating digitally remodulated video from digital components 失效用于从数字组件创建数字重新调制的视频的装置和方法
公开(公告)号：US5008740A
公开(公告)日：1991-04-16
申请号：US339044
申请日：1989-04-14
IPC分类号： H04N9/64
CPC分类号： H04N9/64
摘要： Apparatus and methods for remodulating digital luminance and color difference components for display as PIP information, or together with other composite video components for multi-PIP and test pattern applications are disclosed. A digital encoder is used for conducting a digital quadrature modulation on the color difference components and for digitally adding the luminance signal thereto prior to the converting of the remodulated information into an analog format. Preferably, the digital video information output by the encoder is in the form Y1+(R-Y)1, Y1 +(B-Y)1, Y2-(R-Y)1, Y2-(B-Y)1, Y3+(R-Y)2. Y3+(b-Y)2, Y4 -(R-Y)2, . . . , where Y is the luminance component, R-Y and B-Y are color difference components, and where the numbers index received samples of the video components with the luminance component being sampled at twice the frequency of the color difference components. Where digitally modulated composite video is desired, fixed black level, burst, and background values are multiplexed with the active R-Y and B-Y signals, while fixed sync tip, black level, and background values are multiplexed with the active Y signals prior to encoding.
摘要翻译： 公开了用于重新调制用于显示为PIP信息的数字亮度和色差分量的装置和方法，或与用于多PIP和测试图案应用的其他复合视频组件一起。 数字编码器用于对色差分量进行数字正交调制，并在将重新调制的信息转换为模拟格式之前，对其亮度信号进行数字加法。 优选地，由编码器输出的数字视频信息为Y1 +（R-Y）1，Y1 +（B-Y）1，Y2-（R-Y）1，Y2-（B-Y）1，Y3 +（R-Y） Y3 +（b-Y）2，Y4 - （R-Y）2， 。 。 其中Y是亮度分量，R-Y和B-Y是色差分量，并且其中以亮度分量被采样的视频分量的接收采样的数目为两倍于色差分量的频率。 在需要数字调制复合视频的情况下，固定黑电平，脉冲串和背景值与有源R-Y和B-Y信号多路复用，而固定同步提示，黑电平和背景值在编码之前与有效Y信号进行复用。
-
公开(公告)号：US4994765A
公开(公告)日：1991-02-19
申请号：US505089
申请日：1990-04-04
申请人： David C. Greene , Edwin R. Meyer
发明人： David C. Greene , Edwin R. Meyer
IPC分类号： H03B5/32
CPC分类号： H03B5/32 , Y10S331/03
摘要： A stabilized gated oscillator that provides pulses at a predetermined repetition rate in phase coherence with a gating signal includes a ceramic resonator in a feedback resonant circuit between the output terminal and the input terminal of a linear amplifier. The resonant circuit, which establishes the repetition rate, is constructed to provide an oscillator frequency in a frequency range between two resonant frequencies of the ceramic resonator wherein the ceramic resonator acts as an inductance.
摘要翻译： 在门控信号的相位相干中以预定的重复频率提供脉冲的稳定的门控振荡器包括在线性放大器的输出端子和输入端子之间的反馈谐振电路中的陶瓷谐振器。 建立重复率的谐振电路被构造成在陶瓷谐振器的两个谐振频率之间的频率范围内提供振荡器频率，其中陶瓷谐振器作为电感。
-
公开(公告)号：US4904962A
公开(公告)日：1990-02-27
申请号：US304698
申请日：1989-01-31
申请人： David C. Greene
发明人： David C. Greene
摘要： A gated oscillator circuit for generating a sampling signal for digitally processing television signals, uses an LC oscillator to achieve, high frequency stability and reduced edge jitter. Circuitry is provided on both sides of a tank circuit in the oscillator for decoupling the tank circuit from other active circuit elements thereby enhancing the frequency stability.
-
-
-
搜索结果
4 条记录 (耗时 0.026 秒)
