> One, outline
Is unceasingly thorough along with our country economy
reform and the market economy system gradually establishment, the
highway construction, the path transportation and so on each
transportation enterprise is surmounting the type to move forward, in
order to realize further manages the good transportation market,
guaranteed the transportation security and so on a series of goals,
all levels of traffic department positively is carrying out "the
intelligent transportation": Namely through the utilization
advanced information, the correspondence, the control and so on the
high-tech carries on one kind of information to the tradition
transportation system which the transformation forms,
intellectualized, the socialized new transportation.
After the long-distance bus service, the traveling passenger
train, on the dangerous material carrier vehicle peacefully loads a
car carries the GPS satellite positioning system, may carry on the
real-time monitoring through the center supervisory system to the
vehicles, supervises the pilot overspeed driving, weary driving, the
enhancement transportation production organization water equality to
the control section has the positive assistance management function;
Simultaneously monitors the center to be possible to with to be
in overspeed, comes to anchor and so on the situation long-distance
transport business vehicle implementation reports to the police the
function, thus reduces the traffic accident the formation rate,
enhances the transportation safety in production to have the positive
significance. An item front vehicle carries the GPS system to be
connected the control section and the enterprise knew and positively
is promoting in the application.
Arrogantly stood the electron is specialized is engaged in the
wide band and the wireless data communication high tech company, the
company already promotes a series of GPRS wireless correspondence
product to the market, unifies the newest vehicle to carry the GPS
technology, promoted the new generation of entire IP net reel to carry
the GPS monitoring transmission system, the innovation uses GPRS the
TCP/IP data communication to add the short note backup to substitute
has passed depends entirely on the short note to transmit the data the
mailing address, had the higher overall performance price ratio.
Second, the existing vehicle carries the GPS short note system
analysis
The existing vehicle carries the GPS short note system
communication mainly to select the GSM short note method to realize,
its model application as follows: 1st, existing GPS short note plan technology
characteristic:
The vehicle carries the GPS information machine to carry on the
collection and operation processing to the GPS equipment real-time
gathering automobile positional information.
The vehicle carries the GPS information machine to process after
the information fixed time for to transport tube monitoring center
corresponding SP by the short note transmission or to assign the
handset number.
Transports the tube monitoring center or assigns the handset
number receive corresponding vehicle through SP to carry the GPS
information.
In the peculiar circumstance, transports the tube monitoring
center or assigns the handset number direct transmission short note
control vehicle through SP to carry the GPS system, like the warning
or forces the flameout and so on.
2nd, existing GPS short note plan shortcoming
The transmission time is indefinite: Because the
short note uses time the channel command the crack transmits, does not
have the special data channel, therefore in order time the crack
appears the busy time on is easy to appear the data transfer to retard
or the loss situation.
Channel capacity limited: A short note are most can
transmit 140 effective bytes, cannot comprehensively promptly reflect
the vehicles the real-time information.
Correspondence expense expensive: Basically calculates
according to the receiving and dispatching total strip number.
But extension bad: Take SMS as the main correspondence
link, the link band width influence, is unable further to expand the
future other data transmission services. If in vehicles movement
picture monitoring and so on.
Although the vehicle carries the GPS supervisory system to be
advantageous to the traffic department realizes the traffic control
intellectualization, but the present short note way overall
performance was worse thus has hindered this system comprehensive
promotion.
Third, GPRS development present situation and technical
analysis
GPRS (General Packet Radio Service general grouping
wireless service) is one kind of new grouping exchange data
application service which develops in the existing GSM network.
GPRS is the whole world mobile communication network technology
to the third generation mobile communication (3G) the evolution
mainstream technology and the important milestone, is called 2.5
generation of mobile communication. Compares with the
traditional GSM electric circuit digit dialing exchange, GPRS in the
resources use efficiency, the exchange capacity and the performance
all has a quantitive leap. GPRS has abandoned the traditional
monopoly electric circuit exchange pattern, uses the grouping exchange
technology, each user may simultaneously take many wireless channels,
the identical wireless channel could by many users sharing,
effectively use the channel resources, band width most Gao Keda
171.2Kb/s. At present China moves the GPRS cover scope had
nearly achieved in the key city 100%, had also achieved in the remote
border district above 80%, the practical application band width
probably in 20-40Kb/s, specially suitablly likes profession each kind,
the low gear rate and so on in financial transaction, long-distance
monitor arise suddenly the correspondence demand, completely
substituted for the past tradition wired MODEM, X.25, the number
passes on mailing address and so on the broadcasting station, short
note.
GPRS will use the TCP/IP agreement, is extremely easy and the
existing INTERNET technology and applies the platform conformity, will
cause each kind of IP technology and the service unifies with the
mobile communication technology, will high speed provide each kind for
the customer high speed high-grade to move Che Zaidong the data
communication service. Fourth, the vehicle carries GPS the system GPRS new plan
The thorough analysis existing vehicle carries the GPS
short note system, we thought one kind of network convenient, the
price is higher than on-line, as necessary, the stable mailing
address, but the effective addressing vehicle carries the GPS
supervisory system in the communication transmission question and so
on huge expense, is the vehicle carries the GPS supervisory system in
the transportation profession the universal promoted essential method.
But the present China moves the GPRS network is precisely meets
this need the emerging mailing address, simultaneously take original
SMS as the backup link, definitely may guarantee the GPS supervisory
system data transmission timeliness and the reliability,
simultaneously have the quantitive leap in the performance and the
price aspect. Its network way as follows:
1st, main characteristic:
Communication expense low: The vehicle carries the GPS
supervisory system the correspondence characteristic has the burst
characteristics, but the data quantity is small, to uses GPRS which
costs according to the current capacity extremely to have the
superiority. Take a GPS intelligence transmission as the
example, uses the short news way lowest expense is 0.10 Yuan/.
But selects the GPRS method, the expense reduces is 1 ~ 2 cents
money, reduced above 80%, extremely has the cost superiority.
Data transmission efficiency high: GPRS is one kind of new
migration data communication service, provides the high speed wireless
IP service to the mobile subscriber. The GPS equipment gathers
the positional information after analysis processing, seals in the IP
text of a telegram carries on the transmission, its maximum data
transmission efficiency >90%.
Strong advantageous security measure: The GPRS network
uses GSM the many kinds of physical channel encryption way,
simultaneously in application level, but also provides the central
special line to turn on, security measure and so on special-purpose
the APN, may completely satisfy the transportation management system
to the safe extended request.
But extension strong: Might increase the new monitoring
content according to future service need on GPRS, like increase
picture transmission and so on.
May choose the short note backup: Does not pass in GPRS in
the situation, may guarantee the essential information through the
traditional short note backup way the transmission.
2nd, data central synopsis
Transports the tube monitoring center to turn on
Internet. The GPRS network turns on Internet through motion
bureau GGSN, thus realizes the GPS supervisory system and the data
central network correspondence.
The monitoring center may use correspondence pattern and so on
the ADSL or PSTN, special line puts through INTERNET. The user
may act according to the demand and the expense question nimble
choice.
3rd, the vehicle carries the GPS system synopsis
The vehicle carries the GPS system including the GPS
position finder and GPRS IP Modem. GPS position finder and GPRS
IP Modem through string mouth joint company.
The GPS instrument gathers the position coordinates information
through the satellite positioning system
The GPS instrument transmits orally the positional
information through the string delivers GPRS IP Modem
GPRS IP Modem completes to the coordinates information
analysis and processing.
GPRS IP Modem will process after the string mouth data to
transmit by the TCP/UDP data frame to the GPRS network.
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