CN101833857B - Realizing method for carrying out dynamic traffic guidance by applying broadcasting - Google Patents

Abstract

The invention discloses a realizing method for carrying out dynamic traffic guidance by applying broadcasting, which comprises the following steps of: (1) splitting the traffic information in the current period of time into a plurality of parts by a server as a data-sending end, coding into TS (Transport Stream) packets according to a certain format and broadcasting the coded traffic information data in a data carousel broadcasting mode according to a fixed code rate so that all user terminals can simultaneously receive traffic guidance information; (2) setting each user terminal starting in any time to collect all data sent by the current front-end server in a fixed period of time and avoid the influence of conditions, such as a current user number, startup periods of time, and the like; and (3) bestowing traffic information in different periods of time with different version numbers when the server is used for coding data and collecting the issuing information of a version number by a user terminal to avoid processing subsequently received data packets with the same version number and avoid unmeaning repeated work. The method is used for broadcasting real-time traffic information to all terminals in the carousel broadcasting mode.

Description

A kind of implementation method of carrying out dynamic traffic guidance by applying broadcasting

Technical field:

Broadcast communication of the present invention and information transmission technology field, particularly a kind of technical method that on the transmission system of broadcast mode, utilizes the wheel broadcast mode to realize dynamic traffic guidance.

Background technology:

In recent years, each metropolitan vehicle possess amount sharply increased.Although urban transportation construction and vehicle supervision department drop into great amount of manpower, financial resources and material resources aspect traffic network construction and the traffic administration science and technology Facilities Construction, but still the generation that keeps away unavoidable urban traffic jam, driving is difficult, parking difficulty becomes the ubiquitous problem in each big city.Because randomness and irregularities that traffic participates in can't be planned traffic administration person in advance, also therefore aggravated the pressure of urban traffic control.

The traffic guidance technology is a kind of technology of more effectively managing Modern Traffic, realizing traffic flow optimization.Multiple new and high technology that it is integrated as Geographic Information System, location technology, airmanship, Modern wireless communication technology etc., is used for traffic participant is induced, and makes traffic trip become convenient and swift.

Current domestic system for traffic guiding mainly is to induce based on static state, because being based on the historical data base or the Geographic Information System (map of navigation electronic) of traffic, the static traffic inducible system carries out route guidance, and the out of Memory of traffic information such as current traffic jam, road construction, traffic control and influence trip can not be real-time be reflected to and go in the navigational system, be difficult to the user provide thoughtfully, navigation Service efficiently.

Dynamic traffic inducing system can overcome the shortcoming of traditional static inducible system, the information of path planning institute foundation not only has static road network information, dynamic transport information is more arranged, as real-time road condition information, journey time, traffic hazard, interim traffic control and weather information etc.It has brought convenience for trip, has improved line efficiency.

The dynamic traffic inducing system major part of current existence is to carry out data distributing by point-to-point modes such as GPRS, can also adapt to preferably for the customer group of short run, then can bandwidth resources propose higher requirement when the user increases in enormous quantities.

Summary of the invention:

The objective of the invention is to design a kind of implementation method based on the dynamic traffic guidance of broadcasting.By data broadcasting focus informations such as Real-time Traffic Information, weather, flight wheel is broadcast to each terminal, used fixing bandwidth to support freely increasing of number of users.

Broadcast mode of the present invention mainly is based on digital TV field transport stream (Transport Stream abbreviates TS stream as) and realizes.TS stream is that unit transmits with the TS bag.

The particular content of the inventive method is as follows:

(1) server splits into several portions as data sending terminal with the transport information of current period, be encoded to the TS bag according to certain form, traffic information data wheel broadcast after mode by data broadcasting will encode according to fixing code check is gone, and makes all user terminals can receive traffic guidance information simultaneously like this.

(2) user terminal is set and starts shooting at any time and collect the data that current front-end server sends in can be at a fixed time, can not be subjected to condition effect such as active user's number, on time section.

(3) server is when digital coding, give different version numbers for the transport information of different periods, after user terminal has collected the following photos and sending messages of a version number, the traffic information data bag of the follow-up identical version of receiving number is handled with regard to not needing again, avoided carrying out the insignificant work that repeats.

In the such scheme, need in the described digital coding process traffic information data that transmitting terminal in each set time (server) sends is carried out Version Control, the data of current transmission are decided to be a version, distribute a version number, and the data of current version are split, be encoded into the TS bag respectively, except data, also need deposit the overall budget number of version number, current version, the information such as numbering of current bag in each bag.

After so receiving end was received the TS bag, how many version numbers that just can analyze current data was, needed to receive how many TS bags altogether, and which bag receives that also lacking which bag needs to receive, and controls the operation of reception, decoding with this.When the data of transmitting terminal changed, new version produced, and encodes, sends with new version number.Receiving end can be judged data by version number variation has taken place, and this moment, the data with early version emptied, and received the redaction data.

Under the normal condition, receiving end just can not handled follow-up identical data total data being collected in putting once taking turns data wheel.If fail to collect data because reasons such as packet loss, error in data cause receiving end to take turns data wheel one in putting, then it can put the packet that these omissions are received in the relaying continued access in follow-up data wheel, until collecting total data.

This shows, the data broadcasting that the inventive method adopted, though the state that exists receiving end to receive data can't feed back to the drawback of transmitting terminal, but it is as the data mode of one-to-many, can make full use of limited bandwidth resources, support freely increasing of number of users, this is the superiority that point-to-point mode does not possess.Add the mode that transmitting terminal adopts data wheel to put, current data not stopping paying out again and again seen off.After making that receiving end is started shooting at any time, can collect all data in one period regular time, this is the outstanding part of system for traffic guiding of the present invention just.

In addition, in the such scheme, for the more accurate dynamic information that provides, road need be subdivided into more highway section, certainly will increase the quantity of information of unit interval section like this, therefore need a kind of outstanding coding method of design, data are compressed, to greatest extent the conserve bandwidth resource.Specific as follows:

A) use highway section of road section ID unique identification.Receiving end can obtain the static information such as start-stop position, gps coordinate in highway section by road section ID from database.

B) congestion in highway section is divided into unimpeded, crowded, stop up, no through traffic four kinds of states, use four kinds of colors to represent this four kinds of road conditions on the terminal guidance map.

C) when coding is that unit carries out the data partition with the TS bag, deposits one group of road section ID that congestion is identical in each TS bag, and once getting final product only appears in congestion status.Contain following field in the TS bag successively: the numbering of the overall budget number of version number, current version, current bag, highway section state, road section ID sequence, proof test value.Receiving end is after receiving the TS bag, determine the correctness of whole bag earlier by proof test value, determine the version of this bag then by version number, compare, and whether handle road section information in this bag according to the numbering decision of the overall budget number of current version and current bag with the version of the data that received.

D) generally most of highway section all is unimpeded state, according to this point, coded system is designed to only to send the information that congestion is non-unimpeded highway section, and other highway sections that do not send then are defaulted as unimpeded state, come conserve bandwidth to greatest extent in this way.If the highway section is unimpeded all, then transmitting terminal sends an empty packet that comprises 0 road section information.

Adopt the compression coding scheme of aforesaid way, can reduce data redudancy to greatest extent, reduce the bandwidth that needs, save channel resource.By in each TS bag, only transmitting a kind of traffic information of state, can reduce the redundance of repetition delivery status parameter.By only sending the mode of non-unimpeded state road information, reduced bandwidth usage over half at least.Gather, simulate by traffic related information Shanghai, can not surpass 100kbps even calculate above-mentioned compression coding scheme at traffic peak period occupied bandwidth yet, at the very valuable broadcast industry of bandwidth resources, this can reduce the cost of system greatly.

Description of drawings:

Further specify the present invention below in conjunction with the drawings and specific embodiments.

Fig. 1 is the system chart of the embodiment of the method for the invention.

Fig. 2 is the Data Receiving of receiving end in the method for the invention, the process flow diagram of decoding scheme.

Embodiment:

For technological means, creation characteristic that the present invention is realized, reach purpose and effect is easy to understand, below in conjunction with concrete diagram, further set forth the present invention.

The inventive method application system is in an embodiment formed (concrete structure is referring to Fig. 1) by front end system and terminal system.

Front end system mainly comprises traffic information collection server, transport information scrambler, packing data machine and DAB transmitter.The traffic information collection server is responsible for obtaining real-time transport information from each traffic information collection source, and sends to the transport information scrambler; The transport information scrambler adopts previously described compaction coding method that real-time transport information is classified, encoded, and sends to the packing data machine; The packing data machine is packed other packets in traffic information data bag and the system applies, generates to meet the packet of DAB agreement, and gives the DAB transmitter and send.Each parts of front end system all adopt the industrial computer hardware platform of standard, and the equipment such as corresponding capture card, coding card of arranging in pairs or groups, and use windows XP sp2 operating system.

Terminal system mainly comprises DAB receiver module, transport information decoder module and real-time map display module.Terminal is given the Real-time Traffic Information that the transport information decoder module decodes classification then by the DAB packet that DAB receiver module receiving front-end sends out, and draws out real-time road conditions map by real-time map display module again.

Below according to the system environments in the present embodiment, in conjunction with before disclosed technical scheme, in the specific descriptions system receiving end to data receive, the detailed process (referring to Fig. 2) of decoding.

The receiving end opening initialization is made as an illegal value (i.e. the value that can not occur) with current data version number in the TS bag, begin circulation then and receive the TS bag.Whenever receive a TS bag, at first obtain this TS bag of proof test value and verification and whether have error of transmission that the bag of check errors directly abandons.

After receiving the correct TS of verification bag, at first obtain its version number and number compare,, then empty the data of current version if different with current version, and the version number of this bag as current version number, carry out follow-up Data Receiving.Because new version just begins, the data in this bag must be not receive, and then road section information are wherein analyzed.

If the version number of TS bag and current version are number identical, judge at first whether the bag of current version collects, if collect, then abandon this TS bag, continue to obtain next the bag.If also do not collect, then the numbering according to this bag judges whether to receive this bag, if received, then abandons this TS bag, continues to obtain next bag, if do not receive, then the road section information in this TS bag is analyzed.

After getting access to road section information, then carry out the drawing of navigation map,, receive whenever that perhaps just carrying out map after a part of data refreshes such as can behind the road section information that gets access to a full release, carrying out refreshing of map again according to user's needs.

More than show and described ultimate principle of the present invention and principal character and advantage of the present invention.The technician of the industry should understand; the present invention is not restricted to the described embodiments; that describes in the foregoing description and the instructions just illustrates principle of the present invention; without departing from the spirit and scope of the present invention; the present invention also has various changes and modifications, and these changes and improvements all fall in the claimed scope of the invention.The claimed scope of the present invention is defined by appending claims and equivalent thereof.

Claims (2)

1. the implementation method of a carrying out dynamic traffic guidance by applying broadcasting is characterized in that, comprises the steps:

(1) server splits into several portions as data sending terminal with the transport information of current period, be encoded to the TS bag according to certain form, traffic information data wheel broadcast after mode by data broadcasting will encode according to fixing code check is gone, and makes all user terminals can receive traffic guidance information simultaneously like this;

(2) user terminal is set and starts shooting at any time and collect the data that current front-end server sends in can be at a fixed time, can not be subjected to active user's number, on time section condition effect;

(3) server is when digital coding, give different version numbers for the transport information of different periods, after user terminal has collected the following photos and sending messages of a version number, the traffic information data bag of the follow-up identical version of receiving number is handled with regard to not needing again, avoided carrying out the insignificant work that repeats;

Described method is as follows to concrete steps that data are compressed when digital coding for conserve bandwidth resource to greatest extent:

A) use highway section of road section ID unique identification; Receiving end can obtain start-stop position, the gps coordinate static information in highway section by road section ID from database;

B) congestion in highway section is divided into unimpeded, crowded, stop up, no through traffic four kinds of states, use four kinds of colors to represent this four kinds of road conditions on the terminal guidance map;

C) when coding is that unit carries out the data partition with the TS bag, deposits one group of road section ID that congestion is identical in each TS bag, and once getting final product only appears in congestion status; Contain following field in the TS bag successively: the numbering of the overall budget number of version number, current version, current bag, highway section state, road section ID sequence, proof test value; Receiving end is after receiving the TS bag, determine the correctness of whole bag earlier by proof test value, determine the version of this bag then by version number, compare, and whether handle road section information in this bag according to the numbering decision of the overall budget number of current version and current bag with the version of the data that received;

D) generally most of highway section all is unimpeded state, according to this point, coded system is designed to only to send the information that congestion is non-unimpeded highway section, and other highway sections that do not send then are defaulted as unimpeded state, come conserve bandwidth to greatest extent in this way; If the highway section is unimpeded all, then transmitting terminal sends an empty packet that comprises 0 road section information.

2. according to the implementation method of the carrying out dynamic traffic guidance by applying broadcasting of claim 1, it is characterized in that, need in the described digital coding process traffic information data that transmitting terminal in each set time sends is carried out Version Control, the data of current transmission are decided to be a version, distribute a version number, and the data of current version are split, be encoded into the TS bag respectively, except data, also need deposit the overall budget number of version number, current version, the number information of current bag in each bag.

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