摘要:
The present invention relates to a sending device able to send packets in a network comprising at least two stations, the said device comprising means for extracting image pips on the basis of a synchronization signal, initializing an image counter on the basis of the image pips, initializing a counter every “m” zero-crossings of the image counter, the counter being regulated by a clock produced by the image counter, sampling the counter every period Tsmp, where Tsmp emanates from a time base synchronized on all the stations of the said network; and sending packets containing the samples of the counter in the network. According to the invention, it comprises means for receiving packets containing samples sent by a station of the network as echo to the samples and when samples are received for: evaluating a duration of propagation of samples over an outward-return trip between the said device and the said station; determining a phase shift value Δφ on the basis of the duration of propagation; sending the phase shift value Δφ in the network.
摘要:
The present invention relates to the domain of synchronization of items of equipment connected by a packet switching network. It relates more specifically to a system for generation of a synchronization signal (PIPA, PIPB) and a clock signal (CLK_outA, CLK_outB) by a slave station (SA, SB) connected to a master station (SM) via a packet switching network. The master station (SM) is conformed to produce a master clock signal (CLKM) of frequency FM and a master synchronization signal (PIPM). The master synchronization signal (PIPM) is in phase with the master clock signal (SM). The slave station (SA, SB) comprises the primary synthesis means (SM1A, SM1B) producing a slave periodic signal TICKSA, TICKSB), the periodic signal (TICKSA, TICKSB) is in phase with the master clock signal (CLKM). According to the invention, the slave station (SA, SB) also comprises the secondary means of synthesis (SM2A, SM2B) to synthesize a clock signal (CLK_outA, CLK_outB) and the synchronization signal (PIPA, PIPB) and in that said clock signal (CLK_outA, CLK_outB) and said synchronization signal (PIPA, PIPB) are in phase with said signal (TICKSA, TICKSB).
摘要:
The present invention relates to the domain of video equipment. It relates to a phase-locked loop able to recover the timing of a synchronization signal comprising a temporal discontinuity of amaximum amplitude equal to PCR_Modulus, the loop comprising: a sample comparator comparing the samples and the local samples of a synthesized signal, means for producing the synthesized signal from a corrected signal, a corrector receiving a comparison result delivered by the comparison means and delivering the corrected signal, According to the invention, the comparison means comprises the means to determine a difference in value between the local samples and the samples of the synchronization signal and in that the comparison result has a value that depends on the value ε and on the difference between the value ε and the value PCR_Modulus/2.
摘要:
A synchronization aid device is part of receiving communication equipment of an IP network, having a primary clock signal consisting of primary clock pulses spaced apart by a first period. This device comprises i) a required to increment its value by one unit on each primary clock pulse and reset its value to zero each time it reaches a value M, ii) detection means required to generate a secondary clock pulse each time the value of the counter is zero, the secondary clock pulses forming a secondary clock signal having a second period equal to M times the first period, and iii) control means required, each time the receiving equipment receives a packet containing at least one first bit having a first value, to initialize the counter with a chosen value.
摘要:
A device is disclosed for transmitting packets in a packet communication network comprising at least two stations, including in particular means for generating a first timestamp from a sampled value of a master counter, means for generating a second timestamp from a sampled value of a second counter synchronized on the at least two stations and means for transmitting jointly the two timestamps in the packet communication network. A device is further disclosed for receiving packets in a packet communication network, which uses the double timestamp generated by the transmitter device.
摘要:
The present invention relates to the domain of video equipment. It concerns more specifically a transmission device able to transmit packets, said device comprising the means to extract image ticks from a synchronisation signal, the means to initialise an image counter from said image ticks, the means to initialise a CPT— PCR counter every “m” passage through zero of the image counter, CPT_PCR producing counting ramps CSE_PCR with a range M, the means to sample the counting ramps CSE_PCR every Tech period, where Tech is from a time base synchronised on all the stations of said network, and the means to transmit packets comprising a PCRe sample of the CSE_PCR counting ramp. According to the invention, it also comprises the means to insert in the packet:—an Num index identifying the CSE_PCR counting ramp from which the PCRe sample is realised, and—a time label Datejnit indicating a CSE_PCR counting ramp timestamp passage through a reference value PCR_REF comprised between 0 and M-1.
摘要:
The present invention pertains to a device able to send packets in a packet communication network comprising at least two stations, the said device comprising means for: -extracting image pips on the basis of a synchronization signal; -initializing a first counter on the basis of the said image pips; -initializing a second counter every “m” zero-crossings of the first counter; -sampling the second counter every period Tsmp, where Tsmp emanates from a time base synchronized on all the stations of the said network; and -sending packets containing the samples in the network, characterized in that it comprises, furthermore, means for: receiving at least one phase deviation value Δφ to be applied; -sending the phase deviation value Δφ in the network. The present invention also pertains to a reception device able to receive packets in a packet communication network comprising at least two stations.
摘要:
A device (D2) is dedicated to the reconstruction of clock signals, for example within communication equipment (EQ2) of an IP network. This device (D2) comprises i) a phase-locked loop (BY) having a cut-off frequency dependent, on the one hand, on a configuration value making it possible to reconstruct clock signals according to a chosen clock frequency, and on the other hand, a chosen sampling frequency, and ii) control means (MC2) responsible for forcing the phase-locked loop (BV) to present a variable cut-off frequency according to a received operating mode indication.
摘要:
The present invention relates to the domain of video equipment. More specifically, it concerns a reception device that comprises the means for: receiving packets containing samples, that come from data sampled every Tech period, where Tech is from a time base synchronized on all the stations of said network, regenerating a counting ramp having a count increment and a range value PCR_Modulus, using a phase-locked loop PLL1 that receives the samples and that delivers local samples every Tech period and a reconstituted clock, initializing, at every zero-crossing of the counting ramp, an image counter that is determined by the reconstituted clock. According to the invention, it comprises, further, means for determining the values of count increments.
摘要:
An apparatus for transmitting and receiving packets in a packet switching network that includes at least two stations. The apparatus includes a phase-locked loop, as well as means for receiving packets containing samples of the network, the samples being derived from data sampled every Tech period, where Tech is derived from a time base synchronized on all the stations of the network and the samples being associated with incremental values predicting at least one sample, calculating, in case of interruption of packet reception, a prediction of a sample that should have been received, by adding an increment value to a received sample value.