The long-range environment that GSM short message ceases monitors a station to run state supervisory system to design plan
One, overview:
The existing environment site that monitor installs the place that the unmanned value such as dot of blowdown of outdoors, computer room, enterprise defends for the most part, the moving condition of equipment must rely on a staff member to undertake checking to the spot regularly, waste much labor power and material resources not only so, and because use what regular examination cannot get equipment in real time,run condition, one but equipment occurrence malfunction, must when discovery of the ability when the staff member arrives at the spot, certainly will causes a few needless job error. The key that solves this one problem is how talent is enough mirror the working status of spot equipment in real time to the staff member. Xiamen eaves can the breath of GSM short message of research and development of limited company of electric power science and technology is wireless and long-range supervisory system offerred to be carried out simply, easily for this one problem, the solution with little, credible investment.
2, brief introduction of technology of GSM short information and its characteristic:
Short message serves (a SMS) is GSM technology application serious content, be like,it has a few outstanding characteristics: Can transmit the data of 140 byte, the content of data can be character or number; Pair of end can be carried to transmit inside GSM network, OK still from GSM network outside (like Internet) send short message to give an end points the station; Short message is in the short information center of mobile branch through setting (MSC) makes channel deferent with the letter of GSM system, do not conflict with speech channel, although terminal lies,communicate also can undertake conveying below condition; Convey in short message in the process, the process that does not undertake call join is built and be released; MSC has the memory function of short message, close in terminal unit when machine, can maintain a message to wait effectively inside proper time. Use these characteristics, reach its two-way transmission function, can come true to collect and be controlled remotely to the information of acquisition station equipment conveniently, realize telemetering and remote control namely.
Short information business is GSM/DCS1800 system in do not need exclusively to build end to serve to upright business passageway. Nodding short to the dot message is the alphabetical number string with aleatoric form, control channel to convey through the number. Take up when leisure channel of independent and special control (SDCCH) , news rate is 782b/s; When communicating, take up slow fast channel of the control that follow a road (SACCH) , channel rate is 383b/s. To avoid when had delayed long, and grab to these contending for receive channel negative charge too big, length of the biggest frame is every short message 140 byte (by ASCII character 7bit encode is 160 character) . Because this can be in what any moment are sent or receive short message,transmit TPDU(Transport Protocol Data Unit) of consultative data unit, whether no matter one's voice in speech or data correspond,undertaking. Because public GSM network realized couplet inside global limits,the net is mixed roam, build GSM system to must not establish special communication network again, the short message application that has real time to transmit data function so will be OK make it transmits all sorts of detecting, monitoring data signal and system of communication of control jussive data, can use extensively at terminal of communication of navigation of long-range monitoring, fixed position, individual to wait.
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