CN107483904A - Cable television cut system and channel-splitting filter - Google Patents

A kind of cable television cut system and channel-splitting filter.Including N number of optical sender.1st input interface of any one or more optical senders in N number of optical sender is used to receive the 1st input signal, and the 1st input signal includes broadcast television signal；2nd input interface of optical sender is used to receive the 2nd input signal, and the 2nd input signal is user's request program signal that network quadrature amplitude modulator corresponding with optical sender is sent；Optical sender is used to user's request program signal is converted into optical signal respectively, and the optical signal and broadcast television signal of user's request program signal are sent in a manner of wavelength-division multiplex.Optical sender is increased or decreased according to actual user's quantity situation that program request covers, change to network very little is with regard to that can meet networking demand when lifting program request covering user increase or program request rate, the cost of System Expansion is reduced, system architecture and network O＆M is simplified, reduces operation cost.

Cable television cut system and channel-splitting filter

Technical field

The present invention relates to cable TV transmission technology field, more particularly to a kind of cable television cut system and channel-splitting filter.

Background technology

With direct satellite broadcasting TV, IPTV (Internet Protocol television, IPTV) etc. The appearance of new video transmission technologies, intensified competition of each Virtual network operator in field of video transmission.Therefore Virtual network operator Especially radio and TV operator needs active development video request program (Video On Demand, VOD) technology and application, offer abundant Colorful interactive service, to strengthen the loyalty of user, customer loss is reduced, improves user's average income (Average Revenue Per User, ARPU) value.

VOD business meets TV user individual demand, is that cable TV network operator opens widest interactive increasing Value business.For VOD IVOD business, now mainly there is two ways to realize：One kind is by the orthogonal width of network Degree modulation (Internet Protocol Quadrature Amplitude Modulation, IPQAM) mode, another kind are Realized by IPTV modes.When being interacted by IPQAM, cable tv broadcast passage takes as downlink video passage Certain broadcast channel bandwidth, for bidirectional data path, only need few order program data bandwidth.Line number is entered by IPTV modes During according to interaction, up and down row of channels of the data channel as program request is higher to downlink data bandwidth demand.

In the example of downlink video passage of VOD business is used as by IPQAM modes, including general headend and sub-headend. General headend obtains the resource of corresponding program request by ip router, and the resource is sent to sub-headend.The general headend is also Radio and television optical signal (broadcast TV program signal) is transmitted to sub-headend by optical link.

Use of the sub-headend by the digital broadcast television optical signal of reception and user's request program signal to certain coverage Family is sent.Specifically, sub-headend will send number after program request signal modulation by IPQAM by the long optical transmitter of the straight harmonics of 1550nm Word narrow broadcast TV optical signal.The digital narrow broadcast TV optical signal for being sent the long optical transmitter of the straight harmonics of 1550nm by optical multiplexer It is multiplexed with digital broadcast television optical signal.Optical signal after multiplexing is transmitted through EDFA amplifications distribution and then through optical fiber again, finally Received by photoreceiver.

But the number of users covered with demand (telecommunication) service increases or the lifting of program request rate, the IPQAM in sub-headend is provided Frequency resource be unable to meet demand, single 1550nm directly adjusts the program request stream for intercutting wavelength carrying to be unable to meet demand, now one Aspect needs to increase IPQAM boards, on the other hand needs to reduce the straight EDFA for adjusting and intercutting wavelength and its being followed by covering number of users, The system architecture of whole sub-headend will be made to occur greatly to change, so as to cause cost increase, the operation of network to be deteriorated.

The content of the invention

The application specific embodiment provides a kind of cable television cut system and channel-splitting filter, by setting in the system Multiple optical senders are put, by the way that different optical senders is corresponding from different users respectively, are covered so as to reach increase system While covering user or lifting program request rate, less change system architecture.

On the one hand, the application specific embodiment provides a kind of cable television cut system, and the system is launched including N number of light Machine, N are the positive integer more than or equal to 1；1st input of any one or more optical senders in N number of optical sender Interface is used to receive the 1st input signal, and the 1st input signal includes broadcast television signal；2nd input of the optical sender Interface is used to receive the 2nd input signal, and the 2nd input signal is network quadrature amplitude modulation corresponding with the optical sender User's request program signal that device is sent, the broadcast television signal be fixed frequency wavelength optical signal, user's program request Programme signal is radiofrequency signal；The optical sender is used to user's request program signal is converted into optical signal respectively, and with The mode of wavelength-division multiplex sends the optical signal and broadcast television signal of user's request program signal.

In a possible design, N number of optical sender is connected in series, and the described 2nd to the 1st of N optical senders 1st input signal of input interface input also includes the optical signal that upper level optical sender changes user's request program signal, Wherein, each two optical signal in N number of optical signal that the optical signal of the broadcast television signal and user's request program signal are changed Between wavelength interval be present；The system also includes X channel-splitting filter, and the channel-splitting filter is used to receive the output of N levels optical sender Optical signal and export the optical signal of fixed frequency wavelength, wherein, the optical signal of 1 to Y channel-splitting filter in X channel-splitting filter output Wavelength corresponding to the regional extent of user be, institute identical with the user corresponding to the optical sender being multiplexed by the wavelength It is the positive integer more than or equal to N to state X, and Y positions are less than or equal to X positive integer.

In a possible design, the N of optical signal and user's request program signal conversion of the broadcast television signal Existing wavelength interval is deferred to intensive multiplexed optical wave as defined in International Telecommunication Union and required with wavelength interval between individual optical signal.

In a possible design, the system also includes the high-power image intensifer of multiport；The big work(of multiport Rate image intensifer receives the signal of N optical senders output, and the signal is amplified；The multiple high-power light in port Amplifier also sends the signal after amplification to channel-splitting filter.

In a possible design, the system also includes EDFA Erbium-Doped Fiber Amplifier；The EDFA Erbium-Doped Fiber Amplifier connects The signal of N optical senders output is received, and the signal is amplified；The EDFA Erbium-Doped Fiber Amplifier is also by the letter after amplification Number to channel-splitting filter send.

In a possible design, the channel-splitting filter includes the 1st wavelength division multiplexer, the 2nd wavelength division multiplexer and the 3rd wavelength-division Multiplexer；1st wavelength division multiplexer passes through output by the open optical signal for being total to port and obtaining N optical senders and sending Straight-through port exports the optical signal of Ai wavelength, passes through other wavelength after reflector port output input optical signal removing Ai wavelength Signal；2nd wavelength division multiplexer is used for the optical signal for obtaining the 1st wavelength division multiplexer reflector port by public port and exporting, and Bucket exports the optical signal of B wavelength by exporting straight-through port, passes through other wavelength after reflector port output removing B wavelength Signal；3rd wavelength division multiplexer is used for the optical signal that Ai wavelength is obtained by straight-through port, and is obtained by reflector port The optical signal of B wavelength, it is defeated by public port after the optical signal of Ai wavelength and B wavelength is multiplexed by the 3rd wavelength division multiplexer Go out；Wherein, for the optical signal of Ai wavelength to intercut signal, the optical signal of B wavelength is broadcast singal.

In a possible design, the acquisition of the 1st wavelength division multiplexer, the 2nd wavelength division multiplexer and the 3rd wavelength division multiplexer For dense wave division multiplexer.

In a possible design, the 2nd input interface and a network quadrature amplitude modulation of N number of optical sender The different port connection of device；Or the 2nd input interface and a network quadrature amplitude of Z optical sender in N number of optical sender The different port connection of modulator；Or the 2nd input interface of N number of optical sender and the difference of a network quadrature amplitude modulator Port connects.

Second aspect, the application specific embodiment provide a kind of channel-splitting filter, the channel-splitting filter include the 1st wavelength division multiplexer, 2nd wavelength division multiplexer and the 3rd wavelength division multiplexer；1st wavelength division multiplexer obtains N optical senders hair by the open port that is total to The optical signal sent, and export Ai wavelength by exporting straight-through port and intercut optical signal, input light exported by reflector port Signal removes the signal of other wavelength after Ai wavelength；2nd wavelength division multiplexer is used to obtain the 1st wavelength-division multiplex by public port The optical signal of device reflector port output, and bucket exports the optical signal of B wavelength by exporting straight-through port, it is defeated by reflector port Go out remove B wavelength after other wavelength signal；3rd wavelength division multiplexer is used to obtain Ai wavelength by straight-through port Optical signal, and obtain by reflector port the optical signal of B wavelength, the 3rd wavelength division multiplexer is by Ai wavelength and B wavelength After optical signal multiplexing, exported by public port.

In a possible design, the 1st wavelength division multiplexer, the 2nd wavelength division multiplexer and the 3rd wavelength division multiplexer are close Collect wavelength division multiplexer.

A kind of radio and television broadcast relay system that the application specific embodiment provides, by setting multiple nets in the system Network quadrature amplitude modulator and optical sender, and the actual user's quantity situation covered according to current program request increases or decreases Corresponding network quadrature amplitude modulator and optical sender, to network very little when lifting program request covering user increase or program request rate Change with regard to the actual use networking demand of user can be met, reduce the cost of System Expansion, simplify system architecture And network O＆M, reduce operation cost.

Brief description of the drawings

Figure 1A is a kind of information processing part for radio and television broadcast relay system that the application specific embodiment provides；

Figure 1B is a kind of partial message transmission for radio and television broadcast relay system that the application specific embodiment provides；

Fig. 2 is a kind of channel-splitting filter figure that the application specific embodiment provides；

Fig. 3 is a kind of data transmission system that the application specific embodiment provides.

Embodiment

To make the purpose, technical scheme and advantage of the application clearer, below in conjunction with the application specific embodiment and Technical scheme is clearly and completely described corresponding accompanying drawing.Obviously, described embodiment is only the application one Section Example, rather than whole embodiments.Based on the embodiment in the application, those of ordinary skill in the art are not doing Go out under the premise of creative work the every other embodiment obtained, belong to the scope of the application protection.

Below in conjunction with accompanying drawing, the technical scheme that each embodiment of the application provides is described in detail.

It should be noted that network quadrature amplitude (the Internet Protocol described in the application specific embodiment Quadrature Amplitude Modulation, IPQAM) modulator, collection " scrambling, modulation, frequency transformation " function is one Body, the program stream that it inputs DVB/IP from IP backbone is multiplexed in specified multi-service transport stream again, then carries out QAM tune System and frequency transformation, export radio frequency (Radio Frequency, RF) signal.

Fig. 1 is a kind of cable television cut system that the application specific embodiment provides, wherein, including Figure 1A and figure 1B, described Figure 1A are a kind of information processing part for cable television cut system that the application specific embodiment provides, and are schemed 1B is a kind of partial message transmission for cable television cut system that the application specific embodiment provides.As shown in figure 1, institute Stating system includes receiving broadcast TV program signal and user's request program signal that the general headend is sent.By will be described wide Broadcast TV programme signal and after user's request program signal is multiplexed, inputted to user's set top box, pass through user's set top box pair Played after broadcast TV program signal or the decoding of request program signal.

Specifically, the system includes IPQAM modulators and optical sender.In the present system, IPQAM modulators and light hair Penetrating the quantity of machine can flexibly be adjusted according to the quantity of required covering user.Due to the limit of modulator frequency frequency planning System, the channel that common planning is used for program request is very limited amount of, more than the frequency that program request is distributed in 47~860MHz frequency spectrums Typically at two or three or so, in order to coordinate IPQAM to use (a port exports 8 frequencies) well, program request frequency number is general It is arranged to 8 multiple, thus the conventional frequency that intercuts is planned to 16,24, most 32, thus each insert playing light transmitter is only The order request of specified quantity can be provided.The application is by increasing optical sender (the covering user domain size for reducing optical sender) And corresponding frequency resource is distributed for increased optical sender, so as to improve the quantity or satisfaction of the user of the system covering The lifting demand of program request rate in covering domain.

In the system includes an IPQAM modulator and optical sender example, its general of the IPQAM modulators user User's request program signal that DVB/IP inputs from IP backbone is multiplexed in specified multi-service transport stream again, then is carried out QAM modulation and frequency transformation, export radio frequency (Radio Frequency, RF) user's request program signal.The optical sender is used In reception radio and television.The optical sender is used to the RF request program signals that IPQAM modulators export being converted to program request section Sight signal, then will be exported after the request program optical signal and the multiplexing of broadcast TV program optical signal.The signal of the output The optical signal of the optical signal of first wave length including broadcast TV program signal and the second wave length of request program light.

In the system includes multiple optical sender examples, enter below so that the system includes N number of optical sender as an example Row illustrates, wherein, N is the positive integer more than 1.Described first is connected in series to N optical senders, and N number of light is launched Each optical sender in machine includes the first incoming line and the second incoming line, the second input line of each optical sender Road is used to be connected with IPQAM modulators.First incoming line is used to input the first signal, and second circuit is used to input Secondary signal.

The first signal that the first optical sender in N number of optical sender is inputted by the first incoming line is first wave Long straight broadcast program optical signal, the first optical sender in N number of optical sender inputted by the second incoming line Binary signal be connected with the first optical sender IPQAM modulators output the first request program signal, first program request Programme signal is RF signals.

The first request program signal that first optical sender exports IPQAM modulators is converted to the first request program Optical signal, the first request program optical signal are second wave length.First optical sender is again by first request program Exported after optical signal and the multiplexing of broadcast TV program optical signal.The signal of the output includes the first of broadcast TV program signal The optical signal of the second wave length of the optical signal of wavelength and the first request program light.

Second optical sender is connected with the first optical sender, IPQAM modulators and the 3rd optical sender, wherein, the The outlet line of one optical sender is connected with the first incoming line of the second optical sender, and the second of second optical sender is defeated Enter circuit to be connected with IPQAM modulators, the outlet line of second optical sender and the first input line of the 3rd optical sender Road connects.First optical sender includes the first wave length of broadcast TV program signal to the signal that the second optical sender inputs Optical signal and the first request program light second wave length optical signal.The IPQAM modulators input to the second optical sender Signal include the second program request programme signal, the second program request programme signal is RF signals.

The second program request programme signal that second optical sender inputs IPQAM modulators is converted to the second request program Optical signal, the second request program optical signal are the 3rd wavelength.Second optical sender again inputs the first optical sender Broadcast TV program signal first wave length optical signal and the first request program light second wave length optical signal and Exported after the multiplexing of two request program optical signals.The program signal optical signal of the signal of the output including first wave length, the First request program optical signal of two wavelength and the second request program optical signal of the 3rd wavelength.

3rd optical sender is connected with the second optical sender, IPQAM modulators and the 4th optical sender.The 3rd light hair The signal that machine receives the output of the second optical sender by the first incoming line is penetrated, the 3rd optical sender passes through the second input line Programme signal is thirdly broadcast in road reception IPQAM modulator inputs, and the programme signal of thirdly broadcasting is RF signals.According to above-mentioned Mode, RF signals are converted into optical signal, and the optical signal of two different incoming lines is multiplexed, the signal after multiplexing are passed The optical sender of next stage is defeated by, until N level optical sender output signals.The output signal includes broadcast TV program light Signal, first to N request program optical signals, wherein, the straight broadcast program optical signal is first wave length, the first request program Optical signal is second wave length, N request program optical signals are N+1 wavelength.The first wave length is individual to the N+1 of N+1 wavelength Include the first interval in the optical signal of different frequency range wavelength between any two optical signal respectively and meet certain intervals.Between wavelength Every deferring to intensive light wave as defined in International Telecommunication Union (International Telecommunication Union, ITU) (Dense Wavelength Division Multiplexing, DWDM) wavelength interval is multiplexed to require.

In above-described embodiment of the application, the 2nd input interface and a network quadrature amplitude of N number of optical sender The different port connection of modulator；Or the 2nd input interface of Z optical sender in N number of optical sender is orthogonal with a network The different port connection of amplitude modulator；Or the 2nd input interface and network quadrature amplitude modulator of N number of optical sender Different port connects.

In the specific embodiment of the application, the signal of N optical senders output includes the request program of multiple different wave lengths Optical signal.In order that user receives the request program optical signal corresponding with the program of its program request, the system also includes dividing Ripple device, by channel-splitting filter make user receive its program request program request program optical signal exchanger.Specifically, by a channel-splitting filter User terminal in coverage is divided into a user group, and the user group is corresponding with IPQAM modulators.According to please The user group corresponding to request program information user is asked, by the request program information to corresponding with the user group IPQAM modulators send.The light that the request program information is converted to fixed wave length by the IPQAM modulators again is believed Number, with other optical signals be multiplexed.

In one example, the N optical senders include multiple signal output ports, the multiple signal output port It is connected with channel-splitting filter, is transmitted the optical signal of specified wavelength to designated area respectively by channel-splitting filter.User side reception device connects The signal is received, and is decoded and is played according to the signal.

In another example, also it is connected respectively with multiport image intensifer between the N optical senders and channel-splitting filter, The N optical senders to the multiport image intensifer output include first to N+1 wavelength optical signal.The multiport Image intensifer will be sent to multiple channel-splitting filters respectively after described first to N+1 wavelength optical signal amplification, will by channel-splitting filter The optical signal of specified wavelength transmits to designated area.User side reception device receives the signal, and is carried out according to the signal Decoding and broadcasting.

Fig. 2 is a kind of channel-splitting filter that the application specific embodiment provides.As described in Figure 2, the channel-splitting filter output certain wave Long optical signal.For example, the channel-splitting filter includes the 1st wavelength division multiplexer, the 2nd wavelength division multiplexer and the 3rd wavelength division multiplexer；It is described 1st wavelength division multiplexer is exported by the open optical signal for being total to port and obtaining N optical senders and sending by exporting straight-through port Ai wavelength intercuts optical signal, and the signal of other wavelength after input optical signal removing Ai wavelength is exported by reflector port； 2nd wavelength division multiplexer be used for by public port obtain the 1st wavelength division multiplexer reflector port output optical signal, and bucket pass through it is defeated Go out the optical signal of straight-through port output B wavelength, the signal of other wavelength after removing B wavelength is exported by reflector port；Institute The optical signal that the 3rd wavelength division multiplexer is used to obtain Ai wavelength by output port is stated, and B wavelength is obtained by reflector port Optical signal, the 3rd wavelength division multiplexer by the optical signal of Ai wavelength and B wavelength be multiplexed after, exported by public port.

In the specific embodiment of the application, the optical signal of each output in the multiple channel-splitting filter includes radio and television The optical signal of program and the optical signal of request program, wherein, the optical signal of direct broadcast TV program is first wave length, program request section Purpose optical signal is the 2nd wavelength to N+1 wavelength.Therefore, in the specific embodiment of the application, in the multiple channel-splitting filter The optical signal each exported includes the optical signal of first wave length and the optical signal of the 2nd wavelength into the optical signal of N+1 wavelength Any one wavelength.

It is any one in the optical signal of the optical signal of output first wave length and the optical signal of the 2nd wavelength to N+1 wavelength In the channel-splitting filter of individual wavelength, the channel-splitting filter can be with

In one example, the channel-splitting filter undertakes wavelength selection function, and its input is N+1 wavelength (N number of narrow broadcast wavelength With 1 broadcasting wave length), its output is 1 broadcasting wave length+some narrow broadcast wavelength.The channel-splitting filter is close by the optical element of 3 routines Collecting wavelength division multiplexer (DenseWavelengthDivisionMultiplexing, WDM) composition, (WDM devices are to light wave progress Row synthesis and the device separated).1 broadcasting wave length (λ 0) and 4 narrow broadcast wavelength (1~λ of λ 4) input the first of channel-splitting filter together In individual WDM numberings W10 public port, W10 straight-through port passes through λ 4 wavelength, the λ 3 of 1 λ of reflector port output 0 λ of λ 2 light Ripple, by same method, the λ 3 of 1 λ of W10 reflector ports 0 λ of λ 2 light wave is connected to W11 public port, W11 straight-through port Pass through the light waves of λ 0, the λ 3 of 1 λ of emission port output λ 2 light wave.The λ 0 of light wave λ 4 of W10, W11 straight-through port are connected respectively to W12 Straight-through port and reflector port, in W12 COM port, there have been the light waves of 4 λ of λ 0, the channel-splitting filter to realize wide ripple wavelength X 0 Separated with a narrow broadcast wavelength X 4 from 5 wavelength.

It should be noted that above-mentioned input light wave, output light-wave are only the distance in the application specific embodiment, and can not For the restriction to the application.In the specific embodiment of the application, the signal of each WDM outputs can be set according to being actually needed It is fixed.

In the above example, the optical signal of output first wave length and second wave length is only the act of the specific embodiment of the invention Example, and cannot be used for limitation of the invention.Based on the basic thought of above-mentioned channel-splitting filter, those skilled in the art are without wound The work for the property made, according to being actually needed channel-splitting filter can be made to export any number of wavelengths, the optical signal of any wavelength.

It should be noted that the application is limited without specific the structure type of wavelength division multiplexer, model etc..For example, The wavelength division multiplexer can be respectively intensive multiplexed optical wave (Dense Wavelength Division Multiplexing, DWDM).

Fig. 3 is a kind of data transmission system that the application specific embodiment provides.Such as Fig. 3, including general headend and sub-headend. The general headend provides the resource of broadcast TV program signal and user's request program signal to sub-headend.The sub-headend includes User's request program signal and broadcast TV program signal are obtained from general headend.The sub-headend includes covering model to the system Multiple users in enclosing provide broadcast TV program signal and user's request program signal.

The user by bi-directional set-top box and register one's residence terminal and optical fiber directly to family (Fiber To The Home, FTTH) ray machine connects.The user terminal obtains user's request program signal by FTTH ray machines and straight broadcast TV program is believed Number, network signal is obtained or sent by optical network unit (Optical Network Unit, ONU).

The ip router of the sub-headend receives the request program request that user sends, and the request program request includes User profile and the program of request program request.After the ip router of the sub-headend determines user profile according to the request, by institute Request is stated to send to the ip router of general headend.The ip router of the general headend is asked according to the request by user's distribution Request program resource.

Router is according to the user profile for the network (Internet Protocol, IP) of the general headend, to sub-headend Ip router send program request program resource.The ip router of the sub-headend modulates the request program resource to IPQAM Device is sent, and the port numbers that IPQAM modulators are sent also are included in the request program resource.So as to by IPQAM modulators to Corresponding optical sender sends user's request program signal.The optical sender receives user's program request that IPQAM modulators are sent Programme signal, user's request program signal include request program resource.The optical sender is by user's request program signal Optical signal is converted to by radiofrequency signal, and programme televised live optical signal and request program optical signal multiplexing rear line are sent.

In the specific embodiment of the application, the specific attachment structure of the IPQAM modulators and multiple optical senders can With as shown in figure 1, the optical sender includes carrying out light multiplexing.

When the second input port of multiple optical senders in the system connects from different IPQAM modulators, institute Ip router is stated always according to user profile, it is determined that being sent to the IPQAM modulator corresponding with the user profile.

In the above-mentioned any embodiment of the application, the optical sender can be the straight tunable light emission machines of 1550nm.

It should also be noted that, term " comprising ", "comprising" or its any other variant are intended to nonexcludability Comprising, so that commodity or equipment including a series of elements not only include those key elements, but also including without clear and definite The other element listed, or also include for this commodity or the intrinsic key element of equipment.In the feelings not limited more Under condition, the key element that is limited by sentence "including a ...", it is not excluded that in the commodity including the key element or equipment also Other identical element be present.

It will be understood by those skilled in the art that the application can use complete hardware embodiment, complete software embodiment or combination The form of embodiment in terms of software and hardware.Moreover, the application can use one or more wherein include computer can With in the computer-usable storage medium (including but is not limited to magnetic disk storage, CD-ROM, optical memory etc.) of program code The form of the computer program product of implementation.

Embodiments herein is the foregoing is only, is not limited to the application.For those skilled in the art For, the application can have various modifications and variations.All any modifications made within spirit herein and principle, it is equal Replace, improve etc., it should be included within the scope of claims hereof.