Background technology
The MOST network mainly is responsible for the transfer of data of on-vehicle information amusement and remote information equipment as a kind of vehicle mounted multimedia network-bus, and MOST network utilisation optical fiber transmits entertainment information as transmission medium with ring topology.Fig. 1 is existing MOST network architecture block diagram, and is as shown in Figure 1, and the MOST network can have 64 nodes at most; 64 receiving terminals of promptly maximum series connection; Be installed on mass transit carrier, supply every user to choose different separately amusements, limited the extensibility of network configuration.
Main frame in whole network system as the platform of collecting, integrate, provide all information.Main frame is earlier collected different entertainment information, according to the requirement of each receiving terminal relevant information is packaged into the MediaLB form, and converting thereof into optical signalling again will transmit on the MOST network.Receiving terminal is user's a man-machine interface, and the user proposes relevant information requirement to main frame, and on the MOST network, extracts through receiving terminal, and at the information deblocking of receiving terminal with the MediaLB form, and output is at the display of receiving terminal.Whole system can arbitrarily increase and decrease node in response to the receiving terminal of varying number, and when newly-increased or minimizing node, main frame can distribute the address/numbering of receiving terminal on the MOST network automatically in order, to discern each information requirement from which platform receiving terminal.Propose different entertainment information in response to different receiving terminals in the same time, a large amount of frequency ranges of network demand utilize optical fiber transmission technique, can transmit a large amount of different entertainment information in real time.
As shown in Figure 1; Each node is responsible for transmission information to next node in the MOST network; If middle arbitrary node failure, failure node just can't communicate information to next node, and for example node 3 breaks down; Malfunctioning node 3 just can not communicate information to next node 4, and whole M OST network will leave operating state and be in paralyzed state.On the existing MOST network design and incompatible other popular automotive networking system such as CAN Bus, LIN Bus.If above automobile, the MOST network information can not be communicated by letter with CAN or LIN the MOST network application.
In addition, existing in-car TV solution generally is to utilize the antenna received RF signal, after radio frequency low noise amplifier and more powerful amplifier reinforcement signal strength signal intensity, is sent to the extension set at each seat again.The RF front-end circuit of each extension set can independently carry out demodulation and decoding.But if the in-car TV program all is provided, need use tens pieces of RF front-end circuits to each user on the mass transit carrier, and a powerful amplifier, hardware cost is high.
Have, traditional auto-navigation system need be installed a gps receiver again, calculates current coordinate position behind the reception GPS wireless signal, shows the road information in relevant area again according to the storing map of receiving terminal.But if to each user on the mass transit carrier GPS is provided all, need use tens gps receivers, hardware cost is high.
In a word, existing MOST network, extensibility is limited, and the fault defence capability is low, can't communicate with other automotive networking system.If in-car TV and GPS location all are provided to each user on the mass transit carrier, with high costs.
Embodiment
For the purpose, technical scheme and the advantage that make the embodiment of the invention is clearer, the embodiment of the invention is explained further details below in conjunction with accompanying drawing.At this, illustrative examples of the present invention and explanation thereof are used to explain the present invention, but not as to qualification of the present invention.
As shown in Figure 2, the vehicle-mounted MOST network system of present embodiment comprises: at least two vehicle-mounted MOST networks 201, at least one bridger 202 and stream medium data packetization module 203.Wherein, each vehicle-mounted MOST network 201 comprises a plurality of nodes, like the node among Fig. 1; Bridger 202 connects described vehicle-mounted MOST network; Stream medium data packetization module 203 is packaged as program stream piece group with the program stream piece of user's program request.
As shown in Figure 3, but the framework of being made up of at least two vehicle-mounted MOST networks and at least one bridger can be called the diffused mos T network architecture, and each described vehicle-mounted MOST network comprises a plurality of nodes, (64 nodes can be arranged at most).
But the diffused mos T network architecture can comprise MOST25 network and/or MOST150 network; For example the MOST1 network among Fig. 2 is the MOST25 network; The MOST2 network is the MOST150 network, also can the MOST1 network and the MOST2 network all be the MOST25 network or all be the MOST150 network.Bridger can be the MOST network bridging of different size together.The network architecture of present embodiment can effectively be itself to use the MOST network to increase new MOST specification node, and for example MOST25 and MOST150 can use by bridge joint together, will not change in the lump by original network.
Bridger is regarded as a node in the MOST network. and the software design of bridger need be message packet in the package of MOST.
Said bridger comprises: at least two MOST INIC interfaces and controller, said MOST INIC interface utilizes MediaLB and I2C transfer control signal, message packet and synchronizing signal.Comprise destination address mark in the described message packet, controller can be transferred to destination address with described message packet according to the destination address mark of said message packet.
The MOST network is originally as a ring-type synchronizing network (Ring synchronous network).Each node all can pass to next node to synchronizing signal in the network. and " bridger 1 " can connect two MOST Ring extended network.The present invention can break through a MOST network down in itself 64 nodes limitation and limit; The MOST network can not stop expanding node; 2 MOST networks only are shown among Fig. 2, the invention is not restricted to this, those skilled in the art can know; The present invention can be connected to a plurality of MOST networks through bridger, and is as shown in Figure 4.
In the framework of the MOST of Fig. 3 network, even the node failure in the ring-type synchronizing network can not let the whole network architecture lose efficacy yet, the network architecture still can be kept certain network function, and the MOST stability of network is improved.
MOST network on the right of the bridger of Fig. 3 is connected to the MOST network on the left side can reduce half to the risk that whole network pauses, and for example, when the MOST on the right network node lost efficacy, can not influence left side MOST network.The network architecture among Fig. 3 safeguards that more easily when stopping fixed running like whole network part, other partly still can be worked, and the user can inquire any one node that goes wrong, and the detection of MOST network and maintenance can be easier.
Fig. 5 is the composition sketch map of present embodiment based on the receiving terminal part at main frame and node place in a scalable network framework place onboard system of vehicle-mounted MOST network; As shown in Figure 5; The MOST network transmits information with optical fiber can promote information capacity in a large number; Onboard system can receive and provide multiple different Infotainment, comprises audio input interface, audio-visual input interface (like DVD player), external hard disk machine, USB storage device, SD card, radio signals and television broadcasting signal etc.
Embodiment two
As shown in Figure 6, but the diffused mos T network architecture can also comprise: and the vehicle-mounted CAN network is connected with described MOST network through described bridger; Vehicle-mounted LIN network is connected with described MOST network through described bridger.
As shown in Figure 7, said bridger comprises: at least two MOST INIC interfaces and controller, said MOST INIC interface utilizes MediaLB and I2C transfer control signal, message packet and synchronizing signal.Comprise destination address mark in the described message packet, controller can be transferred to destination address with described message packet according to the destination address mark of said message packet.Controller decision message packet in the bridger is communicated to different purpose ground, MOST for example, and CAN, LIN, this controller can be connected the MOST network with other network standard under MOST definition standard.
In the framework of the MOST of Fig. 6 network, even the node failure in the ring-type synchronizing network can not let the whole network architecture lose efficacy yet, the network architecture still can be kept certain network function, and the MOST stability of network is improved.
The bridger of Fig. 6 links together the MOST network on the left side, the MOST network on the right, following vehicle-mounted CAN network and vehicle-mounted LIN network; Can reduce the risk that whole network pauses; For example; When the MOST on the right network node lost efficacy, can not influence the vehicle-mounted CAN network and the vehicle-mounted LIN network of left side MOST network, bottom.The network architecture among Fig. 6 safeguards that more easily when stopping fixed running like whole network part, other part still can be worked, and the user can inquire any one node that goes wrong, and the detection of MOST network and maintenance can be easier.
As shown in Figure 8, vehicle-mounted MOST network system can also comprise: program stream piece group transport module 1001, data collection module 1002, data distribution module 1003, at least one radio-frequency front-end device 1004 and a gps receiver 1005.
Wherein, program stream piece group transport module 1001 arrives said node with the program stream piece group of stream medium data packetization module 203 packings through same channel transfer.Under the prerequisite that guarantees the Network Transmission bandwidth, in order to simplify the transmission of program stream in network, the present invention adopts the technology of repacking (Data re-packeting on harddisc streaming for video-on-demandapplication) of the hard disk stream medium data of video request program; With the Media Stream in the storage medium; According to broadcast request, piecemeal adds broadcast information again; After reconfiguring packing again, in transmission through network.Like this, can reduce transmission channel, make full use of the network bandwidth, simplify transmission course.
Program stream piece group should satisfy the following formula requirement:
Wherein, T is the program stream transmission intercal, and BW is the network bandwidth, and n is the number of users in the network, and Npkg is the program block number that each user requires at time interval T, and Bpkg is the length (this numerical value is constant) of the program block of customer requirements, and Pid is a user profile length.
Concrete realization instance is shown in Figure 9.In this instance, three user's program requests two program streams in the broadcast nodes, wherein user 1 with user's 3 program requests same program, but because the program request temporal differences, at interval, user 1 requires different pieces with user 3 at one time.The stream medium data packetization module 203 of broadcast nodes adds piece in the program stream 11 and piece 2 respectively user 1 and user's 3 information; And with the piece 3 that adds in the program stream 2 of user's 2 information; New program stream piece group is formed in packing together, through program stream piece group transport module 1001 this program stream piece group is used same channel transfer in network again.The user then through confirming user profile, receives the piece of oneself, ignores other users' piece.Instance is visible thus, and the present invention can utilize same passage to transmit a plurality of users' program block simultaneously through piecemeal reorganization program stream.
Shown in figure 10; Each node comprises a timing watch-dog 301, a master controller 302 and a MOST network controller 303; Regularly watch-dog 301 connects master controller 302 and MOST network controller 303; Real-time and master controller 302 transmits signals, confirms whether master controller 302 and MOST network controller 303 work under normal condition.Shown in figure 11, when timing watch-dog 301 finds that master controllers or MOST network controller break down, control said master controller and get into the pattern that skips over, optical signalling complete be replicated in output.
Data collection module 1002 is collected the preference information that the user chooses through node, and according to said preference information said user is classified; Data distribution module 1003 sends corresponding preference information to sorted users.The vehicle-mounted MOST network system of present embodiment has two-way data transmission capabilities, and the hard disk playing function of its main frame can be selected with different " channel " grantings different classes of film and information to user side.As long as it is, just can comprehensively go out the hobby of a certain particular demographic, thereby promote targetedly, shown in figure 12 user's selection record and analysis.
Because the vehicle-mounted MOST network system of present embodiment can be installed on the mass transportation facilities; So groups of users can be classified to take advantage of specific vehicle route even the period of seat; The repeatability of this classification tool height; Can take advantage of the vehicle of same period of seat and same route every day such as working people; The hobby that therefore can out and outly reflect this group in the collected data of a certain route, rather than with statistical method projection and estimated result, so the effect when this particular course propaganda can promote relatively.
The relative traditional media innovative point of vehicle-mounted MOST network system of present embodiment is that itself is the instrument of a data collection; It also is a good instrument of propaganda; Can in fixed route and time relevant information be provided through advertisement, shown in figure 13, the customer group sorting technique is also the same when collecting data can be with period and route division; Can only compare with dividing time-steps with the advertisement of conventional television broadcast, possess significant advantage.
For example native system is installed on the Tour Bus in one group of contact Hong Kong and Huizhou; Then the travel information of country variant is written into hard disc and broadcasts, through behind the record of several months, just can find with these often this group in contact Hong Kong and Huizhou possibly like travelling to country in Southeast Asia; Thereby propagate targetedly; Comprise and promote its tourism auxiliary facility, travel party, hotel etc.
Radio-frequency front-end device 1004 can be collected a plurality of TV programme, is converted into the MPEG-TS crossfire through after tuning, the channel-decoded machine demodulation, then via the MOST net distribution to each node.The radio-frequency front-end device comprises: radio-frequency tuner, channel decoder and demodulator.
Traditional in-car TV solution is to utilize the antenna received RF signal, after radio frequency low noise amplifier and more powerful amplifier reinforcement signal strength signal intensity, is sent to the extension set at each seat again through copper axis signal line.The RF front-end circuit of each extension set can independently carry out tuning and decoding.But if the in-car TV program all is provided, need use tens pieces of RF front-end circuits to each user on the mass transit carrier, and a powerful amplifier, hardware cost is high.
Let every user can select the TV programme of oneself liking in order to reach with minimum cost and minimum space and weight; The onboard system of this enforcement does not need powerful radio frequency amplifier, provides digital television signal to a plurality of receiving terminals with the radio-frequency front-end device 1004 (comprising radio-frequency tuner and channel decoder and demodulator) of smallest number.The onboard system of present embodiment is collected a plurality of TV programme with two groups of radio-frequency front-end devices; After tuning/channel-decoded and demodulation, change and turn to the MPEG-TS stream format; Need to each on receiving terminal of TV reception via the MOST net distribution, the TV programme of on receiving terminal, selecting then to be comprised in the MPEG-TS crossfire are to decode and to play again.
Gps receiver 1005 can obtain positional information, with said positional information boil down to MPEG-TS crossfire, and through the MOST network said MPEG-TS crossfire is distributed to each node.
Traditional auto-navigation system need be installed a gps receiver on receiving terminal, calculate current coordinate position behind the reception GPS wireless signal, again through the storing map of receiving terminal, shows the road information in relevant area.
But if to each user on the mass transit carrier GPS is provided all, need use tens gps receivers, hardware cost is high.And be not that each user is interested in to see current coordinate position, service efficiency is very low.So the present invention proposes a kind of scheme, a gps receiver and map only are installed on the car machine, the road information of will being correlated with then is compressed into the MPEG-TS crossfire, arrives each user side via the MOST network propulsion again.The receiving terminal end only need use the mpeg decoder of self to understand the MPEG-TS crossfire, and the user just can obtain road information, lowers the cost of system greatly.
Above-described specific embodiment; The object of the invention, technical scheme and beneficial effect have been carried out further explain, and institute it should be understood that the above is merely specific embodiment of the present invention; And be not used in qualification protection scope of the present invention; All within spirit of the present invention and principle, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.