CN1273465A - Method and system for extending broadcast cover in single frequency network - Google Patents
Method and system for extending broadcast cover in single frequency network Download PDFInfo
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- CN1273465A CN1273465A CN 00104841 CN00104841A CN1273465A CN 1273465 A CN1273465 A CN 1273465A CN 00104841 CN00104841 CN 00104841 CN 00104841 A CN00104841 A CN 00104841A CN 1273465 A CN1273465 A CN 1273465A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
- H04H20/65—Arrangements characterised by transmission systems for broadcast
- H04H20/67—Common-wave systems, i.e. using separate transmitters operating on substantially the same frequency
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
- H04H20/02—Arrangements for relaying broadcast information
- H04H20/06—Arrangements for relaying broadcast information among broadcast stations
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H2201/00—Aspects of broadcast communication
- H04H2201/10—Aspects of broadcast communication characterised by the type of broadcast system
- H04H2201/20—Aspects of broadcast communication characterised by the type of broadcast system digital audio broadcasting [DAB]
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Abstract
A system for aligning the phase characteristics of N identical digitized audio program signals distributed from a studio to N broadcasting stations via N time division multiplex (TDM) communication signals includes N TDM multiplexers, each of which (i) multiplexes a digitized audio program signal into at least one channel of a TDM communication link established between the studio and one of the N broadcasting stations, and (ii) multiplexes a timing signal into another channel of the TDM communication signal. The timing signal at the studio and the timing signals at each of the broadcast stations are provided by an existing time distribution network.
Description
The present invention relates to through aerial electromagnetic signal transmission system, the system of synchronous signal emission particularly is provided from least two emission websites that spatially separate.
For enough aerial signal broadcasting coverages of warp are provided to the designated area, supplier can adopt a single emission website usually, utilizes enough power to arrive all parts of this area, or adopts a plurality of places that cover all parts of whole distract.Though two kinds of methods exist defective, wish that more location system reason is because of there is economy and technical reason.For example, in many interested frequencies, the signal of emission is worked in the mode of " sight line ".This shows that signal usually can not (with respect to the emission website) upward transmission in the horizon.In addition, block the zone in some areas of emission website as the geographic barrier of building, bridge, the earth etc. and so on.Economically, many emission websites less, lower-wattage with produce the equal-wattage amount and/or provide a single place of identical broadcasts coverage compare have with operating aspect often more cheap.In addition FCC favorable application point be that emission website existing, different frequency is converted to all in the place of same frequency work can in crowded commercial frequency band, vacate some bandwidth owing to do like this.Figure 1A has illustrated a single high power transmitter that covers interested Zone R, and Figure 1B has illustrated six low-powered transmitters, and each transmitter receives the program of performing in a radio or TV programme live feed from central authorities, covers approximately uniform interested Zone R.Each low-powered transmitter TXn overlay area Rn (all n from 1 to 6).
A defective of the multi-transmitter structural system of Figure 1B is that the receiver in the overlapping region (i.e. the zone that is covered by one or more transmitters, thereby similar from the signal level of different transmitters) is tending towards receiving a plurality of signals.Fig. 2 has illustrated near the receiver M the overlapping region between two transmitter TX1 and the TX2.In this explanation, each transmitter receives audio program to transmitter chain (hereinafter being referred to as STL) from studio, center X through the studio, the studio is to realize by T1 (or E1) digital circuit in the public switch telephone network (hereinafter being referred to as PSTN) to transmitter chain, because the network path of the SLT of TX1 can be longer or shorter than the network path of the STL of TX2, may not exist simultaneously by the audio program of TX1 and TX2 emission.Result near the receiver the overlay region is, along with it from a plurality of transmitter received signals, the output of demodulation will be between the version of two time delays of same audio program " jump ".Some existing system inserts the STL path with fixed delay to postpone with equilibrium path.Yet, when when PSTN (rather than through special circuit) realizes STL, STL may can not keep constant because of a variety of causes such as re-routing the variable process delay of selecting communication link, professional qualification change, data buffering and PSTN switch path delay.
An object of the present invention is to overcome basically deficiency and the defective pointed out above.
The present invention includes and be used to aim at from a studio through the system of N Time Division Multiplexing communication link to the phase property of N identical digitized audio programme signal of N broadcasting station distribution, a described studio and a described N broadcasting station receive a timing signal accurately separately, this system comprises N the TDM multiplexer that is positioned at described studio, each (i) in the wherein said N multiplexer is multiplexed into described digitized audio programme signal at least one channel of the TDM signal of communication of launching to described N broadcasting station from the studio, (ii) the described timing signal accurately that is received by described studio is multiplexed into the one other channel of described TDM signal of communication, for in the described N broadcasting station each, comprising:
(i) TDM demultiplexer is used for removing described digitized audio programme signal and described studio timing signal from a respective signal of described N TDM signal of communication,
(ii) a timing signal comparator is used for described studio timing signal and the local timing signal that postpones skew are compared with the generation comparative result, and the generation shift time corresponding with described comparative result; With
(iii) one postpones regulating circuit, is used for the delay of dynamic adjustments as the described TDM signal of communication of the function of described shift time, and wherein said delay regulating circuit preferably is collisionless (hitless) substantially.
The present invention also comprises a kind of being used to aim at from a studio by the method for N Time Division Multiplexing signal of communication to the phase property of the individual identical digitized audio programme signal of the N of N broadcasting station distribution, a described studio and a described N broadcasting station receive timing signal accurately separately, comprising:
Described digitized audio programme signal is multiplexed into from least one channel of the TDM signal of communication of the emission of described studio to a described N broadcasting station;
The described timing signal accurately that is received by described studio is multiplexed into the one other channel of described TDM signal of communication; With
For in the described N broadcasting station each,
A respective signal from described N TDM signal of communication is removed described digitized audio programme signal and described studio timing signal,
Described studio timing signal and local timing signal are compared with the generation comparative result, and the generation shift time corresponding with described comparative result; With
Dynamic adjustments is as the delay of the described TDM signal of communication of the function of described shift time, so that drive described shift time is zero substantially, and comprise that with the step of the described phase delay of the described audio program of collisionless mode dynamic adjustments basically wherein further step comprises from the time distribution network that is pre-existing in and receives the described accurate timing signal each.
Advantageously, a kind of system that is used to aim at from a studio phase property of N the identical digitized audio programme signal of distributing to N broadcasting station through N Time Division Multiplexing communication link.A studio and N broadcasting station receives timing signal accurately separately.This system comprises N the TDM multiplexer that is positioned at the studio.Each (i) in N multiplexer is multiplexed into the digitized audio programme signal at least one channel of the TDM communication link of setting up between in studio and N broadcasting station one and (ii) the timing signal accurately that is received by the studio is multiplexed into one other channel in the TDM communication link.In N broadcasting station each comprises the TDM demultiplexer, timing signal comparator and postpone regulating circuit.The respective links of TDM demultiplexer from N TDM communication link removed digitized audio programme signal and studio timing signal.The timing signal comparator relatively also produces the shift time corresponding with described comparative result with the studio timing signal with local timing signal.Postpone of the delay of regulating circuit dynamic adjustments as the digitized audio programme signal of the function of described shift time.In one embodiment, postponing the delay of regulating circuit dynamic adjustments digitized audio programme signal so that drive shift time is zero substantially.
In another embodiment of the present invention, postpone the essentially no collision of regulating circuit.Term " collisionless " be meant can be in postponing the output sequence of unit of digital data obliterated data or do not produce under the situation in gap and realize postponing to change not.
In another embodiment of the present invention, provide timing signal accurately by global positioning system (GPS) receiver.
In another embodiment of the present invention, the TDM communication link comprises the sound framer circuit that is used for the T1 communication link.
In another embodiment of the present invention, the TDM communication link is unidirectional basically, so that timing signal and program audio signal data flow to one corresponding N the broadcasting station from the studio.
In another embodiment of the present invention, this system further comprises an audio card that is arranged in the studio and is positioned at each the essentially identical audio card in N broadcasting station, wherein the audio card of studio is with the analogue audio frequency program digitalization, and the audio card in each broadcasting station converts digitized audio program to the analogue audio frequency program.
In another embodiment of the present invention, each audio card keeps audio signal to be always the linear phase delay on interested audio signal frequency band, thereby keeps constant audio signal group delay.
In another embodiment of the present invention, audio card comprises at least one FIR filter, to guarantee constant group delay.
With reference now to accompanying drawing, the present invention is described as an example, wherein:
Figure 1A illustrated of covering interested Zone R single, high power transmitter;
Figure 1B has illustrated provides the combination that is similar to six low-powered transmitters of identical coverage with the transmitter of Figure 1A;
Near the receiver of Fig. 2 explanation overlay region between two transmitters shown in Figure 1B; With
Fig. 3 illustrates the block diagram of signal distribution system.
Fig. 3 shows and is used to aim at from a studio through the block diagram of N Time Division Multiplexing communication link to a preferred embodiment of the signal distribution system 100 of the phase property of N identical digitized audio programme signal of N broadcasting station distribution.The embodiment of illustrated system 100 comprises 102, the first broadcasting places 104, scene, a studio and the second broadcasting place 106.Other embodiment of system 100 broadcasts the place though can comprise a plurality of (being certain Integer N).Scene, studio 102 comprises center time reference 110, audio program source 112, the one TDM multiplexers, 114, the first emission (TX hereinafter referred to as) voicefrequency circuit 116, the two TDM multiplexers 118 and the 2nd TX voicefrequency circuits 120.Generalized embodiment with this system in N broadcasting place comprises N TDM multiplexer and N TX voicefrequency circuit, so that each broadcasting station comprises that at scene, studio 102 a TDM multiplexer/voicefrequency circuit is right.Therefore, in the illustrated embodiment, scene, studio 102 comprises that two TDM multiplexer/voicefrequency circuits are right: 114/116 and 118/120.Each TDM multiplexer/voicefrequency circuit is to 112 receiving audio program signals 124 from center time reference 110 receiving center timing signals 122 and from the audio program source.A TDM multiplexer/voicefrequency circuit to 114/116 in, TDM multiplexer 114 receives timing signals 122, and TX voicefrequency circuit 116 receives audio program signals 124.The 2nd TDM multiplexer/voicefrequency circuit to 118/120 in, TDM multiplexer 118 receives timing signals 122, and TX voicefrequency circuit 120 receives audio program signals 124.Right for each TDM multiplexer/voicefrequency circuit, digitlization of TX voicefrequency circuit and the audio program signal 124 that handle to receive, and digitized signal 126 offered corresponding TDM multiplexer. TX voicefrequency circuit 116 and 120 utilizes Digital Signal Processing (hereinafter being referred to as DSP) technology, for example finite impulse response (hereinafter being referred to as FIR) filter keeps constant group delay, and keeps accurate and uniform phase alignment by voicefrequency circuit 116 and 120 thus.TDM multiplexer distribute digital signal 126 and timing signal 122 in spendable a plurality of time slots in output TDM signal.The one TDM multiplexer 118 produces a TDM 128, the two TDM multiplexers 120 that transmit and produces the 2nd TDM and transmit 129.Therefore, by TDM timing signal 122 conveyings of the corresponding digitized program signal 126 of packet handles and the audio signal programme signal 124 of 128 and 129 emissions that transmit with " time tag " this digitized signal 126.In other words, the timing signal 122 that sends together with digitized signal 126 in the TDM output signal provides with scene, studio 102 when send the relevant information of digitized signal 126.
The first broadcasting place 104 comprises a TDM demultiplexer 130, first local time reference, 132, the first timing signal comparators 134, the first postpone regulating circuit 136, first postpones skew 137, the first receives (hereinafter being referred to as RX) voicefrequency circuit 138 and exciter/transmitter module 139.First postpones regulating circuit 136 receptions transmits 128 by the TDM that the TDM multiplexer 116 that is positioned at scene, studio 102 produces, and the delay version of TDM signal 128 is offered TDM demultiplexer 130.TDM demultiplexer 130 is removed digitized signal 126 and timing signal 122 from the suitable time slot that TDM transmits 128, with digital audio signal 140 that produces recovery and the timing signal 142 that recovers, and by local time reference 132 local timing signals 144 that produce and that postpone by delay skew 137 subsequently.Timing signal comparator 134 produces and the timing signal 142 of recovery and the time difference time corresponding shifted signal 146 between the local timing signal 144.Postponing regulating circuit 136 time of reception shifted signals 146 and regulating its retardation that is applied to TDM signal 128 serves as zero with driving time shifted signal 146.For driving time shifted signal 146 is zero, the equation below must satisfying:
[postponing the delay of skew 137]=[postponing the delay of regulating circuit 136]+[PSTN delay]
The delay that postpones skew 137 must postpone big than the expection PSTN of maximum.Perform in a radio or TV programme station program audio 126 if transmit simultaneously in all broadcasting stations, the delay skew in all broadcasting stations must be identical.In alternative embodiment, can be different broadcasting stations and set different delay skews 137, transmit program audio 126 at different time to different broadcasting stations.This arranges to allow overlapping region slightly simplified between the adjacent broadcasting station.For example, the best position of equal power between two adjacent broadcasting stations, overlay region.If two adjacent broadcasting stations have unequal power, the position of equal power is not equidistant with each broadcasting station, but is positioned at the broadcasting station of more close lower-wattage.By control lag skew 137 delays that provide, can make the overlay region appear at the position of equal power exactly.
U.S. Patent No. 5,818 discloses an example that postpones regulating circuit 136 in 769 the specification.Delay line has been realized the change to the throughput delay of a series of unit of digital data, preferably with the collisionless pattern.Term " collisionless " is meant under the situation that produces the gap in the output sequence of obliterated data not or the unit of digital data that do not postponing and realizes postponing to change.Delay line also can, can begin to postpone to change when loss of data in this sequence unit of digital data of tolerable or the gap in this sequence unit of digital data during the pattern in " collision " immediately with " collision " pattern work.Voicefrequency circuit 138 receives digital audio signal 140 and produces the audio signal of handling as the function of digital audio signal 140 148.Exciter/transmitter 139 receives the audio signal of handling 148 and produces will be by the modulated carrier signal 150 of antenna module 152 emissions of disposing.
The second broadcasting place 106 comprises the 2nd TDM demultiplexer 160, second local time reference 162, second timing signal comparator 164, the second postpones regulating circuit 166, second postpones skew 167, the second receives (hereinafter being referred to as RX) voicefrequency circuit 168 and exciter/transmitter module 169.Usually, the parts in second broadcasting station 106 are to operate and reciprocation with the essentially identical mode of the parts in first broadcasting station 104.Second postpones regulating circuit 166 receptions transmits 129 by the 2nd TDM that produces at the TDM at scene, studio 102 multiplexer 120, and the delay version of TDM signal 129 is offered TDM demultiplexer 160.TDM demultiplexer 160 is removed digitized signal 126 and timing signal 122 from the suitable time slot that TDM transmits 129, with digital audio signal 170 that produces recovery and the timing signal 172 that recovers, and by local time reference 162 local timing signals 174 that produce and that postpone by delay skew 167 subsequently.Timing signal comparator 164 produces and the timing signal 172 of recovery and the time difference time corresponding shifted signal 176 between the local timing signal 174.Postponing regulating circuit 166 time of reception shifted signals 176 and regulating its retardation that is applied to TDM signal 129 serves as zero with driving time shifted signal 176.For driving time shifted signal 176 is zero, the equation below must satisfying:
[postponing the delay of skew 167]=[postponing the delay of regulating circuit 166]+[PSTN delay]
The delay that postpones skew 167 must postpone big than the expection PSTN of maximum.Perform in a radio or TV programme station program audio 126 if transmit simultaneously in all broadcasting stations, the delay skew 167 in all broadcasting stations must be identical.In alternative embodiment, can be different broadcasting stations and set different delay skews 167, transmit program audio 126 (as in the first broadcasting place 104, describing) at different time to different broadcasting stations.Voicefrequency circuit 168 receives digital audio signal 170 and produces the audio signal of handling as the function of digital audio signal 170 178.Exciter/transmitter 169 receives the audio signal of handling 178 and produces will be by the modulated carrier signal 180 of antenna module 182 emissions of disposing.
The RX voicefrequency circuit 138 and 168 that is positioned at broadcasting place 104 and 106 adopts the DSP technology separately respectively, and for example, the FIR filter is so that keep constant group delay by the RS voicefrequency circuit.Constant group delay is used for safeguarding the accuracy and consistent all the time phase alignment of the audio program signal of broadcasting by the RX voicefrequency circuit.
In N the TDM signal that is produced by studio on-the-spot 102 each is sent to N of broadcasting in the place through digital transmission channel.Though other transmission medium well known by persons skilled in the art can provide this channel, in a preferred embodiment, public switch telephone network (hereinafter being referred to as PSTN) provides digital transmission channel.Though can use other communication as E1, ATM, TCP/IP, Ethernet, ISDN or alternate manner and so on to transmit mechanism in alternative embodiment, in a preferred embodiment, the T1 circuit among the PSTN provides transmission channel.One from scene, studio 102 to the broadcasting station 104 or 106 T1 digital transmission link definition of T DM agreement and implement sound framing algorithm, the signal interruption that causes with the bit error that prevents because of Network Transmission.Usually, the T1 link comprises 24 different TDM time slots, and each time slot is carried the information of 8 bits.Utilize 24 TDM time slots of every group to comprise that a single framing bit is 193 bits to form a frame.The framing bit of 12 successive frames forms a single sign indicating number type, and receiving equipment uses this single sign indicating number type to set up frame synchronization.The transmission rate of T1 link is per second 1.544 megabits (hereinafter being referred to as MBPS), and therefore the maximum usable data rates of any single time slot is per second 64 kilobits (hereinafter being referred to as KBPS).By the TDM structural system of T1, can on a single T1 link, launch 24 different 64KBPS channels.For increasing bandwidth, individual channel can use more than a time slot.For example, if two time slots are used for an individual channel, channel capacity is increased to 128KBPS.If whole 24 time slots are used for an individual channel, this system reaches the maximum channel capacity of 1.536MBPS.
Center time reference that is positioned at scene, studio 102 and the local time reference 132 and 162 that lays respectively at broadcasting place 104 and 106 are carried out synchronously, so that provide the essentially identical time in each place.In other words, timing signal 122, local timing signal 144 and local timing signal 174 are always basic identical.In a preferred embodiment, utilize global positioning system (GPS) receiver be arranged in scene, studio 102 and each of broadcasting place 104 and 106 to realize this time synchronized.Gps system is the network of the geostationary orbit satellite of close synchronization on time.Satellite is mainly broadcasted location and the date and time information that ground receiver utilizes continuously for navigation purpose.Yet owing to satellite is carried out the local time information of synchronous and every satellite broadcasting its oneself on time, the GPS network also can be used for the ground site of extensive distribution is carried out time synchronized effectively.In a preferred embodiment of the invention, each GPS receiver is attended by the local zone time source for local frequency source reference.Local frequency source can comprise temperature compensating crystal oscillator, constant temperature (ovenized) oscillator, rubidium oscillator, caesium oscillator, hydrogen maser type (hydrogen maser) or other frequency source.Lose at short cycle under the situation of gps signal, the effect of " flywheel " can be played in the local zone time source, so that recovering to keep system works before the gps signal.
In addition, gps satellite comprises split-hair frequency reference, and the GPS receiver can recover frequency signal accurately from satellite broadcasting.Therefore, the GPS receiver can provide accurately that frequency source uses for juxtaposed equipment, as long as this receiver remains to the link of satellite.Be positioned at a receiver locking carrier frequency in each place, broadcasting station, thereby each broadcasting place is locked onto common reference.
Main practicality of the present invention is its ability to the little delay change dynamics compensation in the distribution network (for example public switch telephone network) between studio on-the-spot 102 and broadcasting place 104 and 106.Should equate the path delay of each ideally, from central studio place 102 to the broadcasting station.The obliterated data or insert the gap in serial data not because the delay regulating circuit of each broadcasting in place can change its throughput delay, this system can keep desirable equal path to postpone and not destroy or interrupt audio program.The precision of system mainly is subjected to the restriction of the temporal resolution of the TDM communication link between studio and the broadcasting station.For example, use T1 TDM communication link that this system can will be controlled in plus or minus two microseconds from the scene, studio to each path delay of broadcasting place (with respect to absolute standard).Can utilize communication link that precision is provided with bigger resolution.In a preferred embodiment, systemic resolution 0.1 microsecond, in other words, can the step bias internal studio of 0.1 microsecond on-the-spot with the broadcasting place between independent path delay, to optimize the performance of this system in broadcasting the overlay region.In other embodiments, can improve delay circuit (as in ' 769 patents, describing in detail) so that increase or reduce systemic resolution according to the performance requirement of system.
Be used to aim at from a studio through N Time Division Multiplexing signal of communication and comprise N TDM multiplexer to the system of the phase property of N same numbers audio program signal of N broadcasting station distribution, each multiplexer (i) is multiplexed into the digitized audio programme signal at least one channel of the TDM communication link of setting up in one of this studio and N broadcasting station and (ii) timing signal is multiplexed in the one other channel of TDM signal of communication.Be positioned at TDM signal of communication extraction digitized audio programme signal and the timing signal of the TDM demultiplexer in each broadcasting station from correspondence.The timing signal comparator compares the timing signal of extraction and the local timing signal of pressing accurately and the scalable amount postpones, and produces the shift time corresponding with this comparative result.Postponing the delay of the best dynamic adjustments of regulating circuit as the TDM signal of the function of shift time, is zero so that drive shifted signal substantially.Utilize existing time distribution network to be provided at the timing signal of studio and at the timing signal in each broadcasting station.
Claims (10)
1. one kind is used to aim at from a studio through the system of N Time Division Multiplexing signal of communication to the phase property of N same numbers audio program signal of N broadcasting station distribution, a described studio and a described N broadcasting station receive timing signal accurately separately, this system comprises N the TDM multiplexer that is positioned at described studio, it is characterized in that: each (i) in the described N multiplexer is multiplexed into described digitized audio programme signal from described studio at least one channel of the TDM signal of communication of one of described N broadcasting station emission, (ii) the described timing signal accurately that is received by described studio is multiplexed in the one other channel of described TDM signal of communication, for each broadcasting station in the described N broadcasting station
(i) TDM demultiplexer is used for removing described digitized audio programme signal and described studio timing signal from the respective signal of described N TDM signal of communication,
(ii) a timing signal comparator is used for described studio timing signal and the local timing signal that postpones skew are compared with the generation comparative result, and the generation shift time corresponding with described comparative result; With
(iii) one postpones regulating circuit, is used for the delay of dynamic adjustments as the described TDM signal of the function of shift time, and wherein said delay regulating circuit is collisionless substantially.
2. system according to claim 1, wherein provide described accurate timing signal by the time distribution network that is pre-existing in, the described time distribution network that is pre-existing in comprises global positioning system (GPS) satellite network, and provides described accurate timing signal by at least one GPS receiver.
3. system according to claim 1, wherein said TDM signal of communication comprises the T1 signal of communication, wherein said TDM signal of communication also comprises the E1 signal of communication.
4. system according to claim 3, wherein said TDM signal of communication is unidirectional substantially, consequently described accurate timing signal and described program audio signal flow to described in the described N broadcasting station from described studio.
5. system according to claim 4, wherein each described digitized audio programme signal comprises the frequency band that is enough to carry exactly the hi-fi music program, and comprises the dynamic range that is enough to carry exactly the hi-fi music program.
6. system according to claim 5, wherein each described digitized audio programme signal is carried the channel of at least one monophony information, or each described digitized audio programme signal is carried the channel of at least two stereo informations.
7. system according to claim 1, it is characterized in that: the studio card and the essentially identical audio card that is positioned at described N each station, broadcasting station that are arranged in described studio, described studio audio card is with the analogue audio frequency program digitalization, each described broadcasting station audio card converts described digitized audio program to described analogue audio frequency program, each described audio card keeps described audio signal to be always the linear phase delay on interested audio signal frequency band, thereby keep constant audio signal group delay, wherein said audio card comprises at least one FIR filter, so that keep described constant group delay.
8. system according to claim 1, the described delay of the described TDM signal of communication of wherein said delay regulating circuit dynamic adjustments is zero so that drive described shift time substantially.
9. one kind is used to aim at from a studio through the method for N Time Division Multiplexing signal of communication to the phase property of N same numbers audio program signal of N broadcasting station distribution, a described studio and a described N broadcasting station receive timing signal accurately separately, it is characterized in that:
Described digitized audio programme signal is multiplexed into from described studio at least one channel of the TDM signal of communication of one of described N broadcasting station emission;
The described timing signal accurately that is received by described studio is multiplexed in the one other channel of described TDM signal of communication; With
For each broadcasting station in the described N broadcasting station,
Respective signal from described N TDM signal of communication is removed described digitized audio programme signal and described studio timing signal;
Described studio timing signal and local timing signal are compared with the generation comparative result, and the generation shift time corresponding with described comparative result; With
Dynamic adjustments is as the delay of the described TDM signal of communication of the function of described shift time, with the step that comprises with the described phase delay of the described audio program of collisionless substantially mode dynamic adjustments, wherein further step comprises from the time distribution network that is pre-existing in and receives each described accurate timing signal.
10. one kind is used to aim at from a studio through the system of N Time Division Multiplexing communication link to the phase property of N identical digitized audio programme signal of N broadcasting station distribution, a described studio and a described N broadcasting station receive timing signal accurately separately, comprising:
Be positioned at N TDM multiplexer of described studio, each (i) in the wherein said N multiplexer is multiplexed into described digitized audio programme signal at least one channel in the TDM communication link of setting up between in a described studio and a described N broadcasting station one and (ii) the timing signal accurately that is received by described studio is multiplexed into one other channel in the described TDM communication link;
For in the described N broadcasting station each,
(i) TDM demultiplexer is used for removing described digitized audio programme signal and described studio timing signal from a respective links of described N TDM communication link,
(ii) a timing signal comparator is used for described studio timing signal and local timing signal are compared with the generation comparative result, and the generation shift time corresponding with described comparative result; With
(iii) postpone regulating circuit, be used for the delay of dynamic adjustments as the described digitized audio programme signal of the function of described shift time.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US28265299A | 1999-03-31 | 1999-03-31 | |
| US09/282,652 | 1999-03-31 |
Publications (1)
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|---|---|
| CN1273465A true CN1273465A (en) | 2000-11-15 |
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|---|---|---|---|
| CN 00104841 Pending CN1273465A (en) | 1999-03-31 | 2000-03-30 | Method and system for extending broadcast cover in single frequency network |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP1041758A3 (en) |
| CN (1) | CN1273465A (en) |
| TW (1) | TW507428B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007134486A1 (en) * | 2006-05-24 | 2007-11-29 | Zte Corporation | A synergetic transmitting system for digital broadcast sfn and method thereof |
| CN101355778B (en) * | 2007-07-27 | 2012-05-23 | 中兴通讯股份有限公司 | Single frequency network system, working method thereof and mobile communication system superposing the same |
| CN105356959A (en) * | 2008-12-31 | 2016-02-24 | 艾比奎蒂数字公司 | Synchronization of separated platforms in an HD radio broadcast single frequency network |
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| US7512175B2 (en) * | 2005-03-16 | 2009-03-31 | Ibiquity Digital Corporation | Method for synchronizing exporter and exciter clocks |
| US7865610B2 (en) | 2007-03-12 | 2011-01-04 | Nautel Limited | Point to multipoint reliable protocol for synchronous streaming data in a lossy IP network |
| FR2927747B1 (en) | 2008-02-19 | 2010-03-19 | Tdf | METHOD FOR BROADCASTING A DATA STREAM IN A NETWORK COMPRISING A PLURALITY OF TRANSMITTERS, COMPUTER PROGRAM PRODUCT, NETWORK HEAD AND CORRESPONDING SYSTEM. |
| EP3018842B1 (en) | 2014-11-04 | 2017-03-22 | Schleifring und Apparatebau GmbH | Method and device for the adjustment of contactless data links |
| KR20180123572A (en) * | 2016-03-29 | 2018-11-16 | 게이츠에어, 아이엔씨. | Time-multiplexed spectrum sharing |
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| GB9111313D0 (en) * | 1991-05-24 | 1991-07-17 | British Telecomm | Radio system |
| US5822324A (en) * | 1995-03-16 | 1998-10-13 | Bell Atlantic Network Services, Inc. | Simulcasting digital video programs for broadcast and interactive services |
| US6011977A (en) * | 1995-11-30 | 2000-01-04 | Ericsson Inc. | RF simulcasting system with dynamic wide-range automatic synchronization |
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2000
- 2000-02-19 TW TW89102903A patent/TW507428B/en not_active IP Right Cessation
- 2000-03-14 EP EP00105296A patent/EP1041758A3/en not_active Withdrawn
- 2000-03-30 CN CN 00104841 patent/CN1273465A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007134486A1 (en) * | 2006-05-24 | 2007-11-29 | Zte Corporation | A synergetic transmitting system for digital broadcast sfn and method thereof |
| US8068452B2 (en) | 2006-05-24 | 2011-11-29 | Zte Corporation | Synergetic transmitting system for digital broadcast SFN and method thereof |
| CN101355778B (en) * | 2007-07-27 | 2012-05-23 | 中兴通讯股份有限公司 | Single frequency network system, working method thereof and mobile communication system superposing the same |
| CN105356959A (en) * | 2008-12-31 | 2016-02-24 | 艾比奎蒂数字公司 | Synchronization of separated platforms in an HD radio broadcast single frequency network |
| CN105356959B (en) * | 2008-12-31 | 2018-06-15 | 艾比奎蒂数字公司 | The synchronization of the platform of separation in HD radio broadcasting single frequency networks |
Also Published As
| Publication number | Publication date |
|---|---|
| TW507428B (en) | 2002-10-21 |
| EP1041758A2 (en) | 2000-10-04 |
| EP1041758A3 (en) | 2004-03-03 |
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