Welcome toChina GPS Navigation Network
Add to Favorites | 中文版
Global satellite navigation system (the development general situation of GPS)
From;    Author:Stand originally

Summary today, satellitic navigation system has been used extensively in a large number of application, and total development trend is to be real time application to provide high accuracy service. Up to now, more perfect satellite navigation system has had American GPS and Russia GLOMSS system, their fixed position and time precision can satisfy fixed position of firm for military use and time requirement. Face many satellitic navigation demand, europe plans to roll out Galileo of his satellitic navigation system. The article undertook describe and be comparatived to existing CPS and GLONASS system, undertook brief specification to the plan plan of Galileo system.

Thematic word: Navigation of satellite communications of global location system

Navigation and fixed position are very significant to a lot of activities. But, before a lot of navigation and technology of fixed position TRANBBS are existing the blemish of different level. Landmarks is confined to this locality to use, get even the influence of motion and environmental element; The technology of DeadReckoning is very sophisticated, its precision relies on more primitive measurement tool; Celestial technology is very sophisticated also, and suit the case with night and good weather to use only, measure precision finite also; OMEGA is based on less wireless and directional beacon, not only precision suffers radio interference finite and easily; LORAN covers range finite (basically be the coast) , precision suffers the effect of geographical state, suffer interference easily; SatNav is based on low quite much general to strap measure, suffer the effect with mobile receiver easily, satellitic amount is little, data is updated not seasonable. System of location of global navigation satellite (GPS) , what the development of the GLONASS of Russia developed exact location is epochal, make the dominant technology that contemporary navigation uses. The development of navigation system of Galileo Europe satellite will be the fixed position of civil user and time service to offer another alternative.

GPS system

The development setting of 1.GPS system

20 centuries 70 time, as contest of equipment of beautiful Su Jun upgrade, urgent need can be in martial domain of the United States worldwide spirit is certain system. American department of defense nots hesitate 12 billion dollar develops denounce endowment system of location of for military use. 1978, the United States launched the first satellite that is used at GPS system successfully, after this GPS develops gradually make the system that uses extensively at present.

2.GPS system is summarized

GPS system is measured by dimensional part, ground accuse part and user facilities 3 parts composition.

(1) dimensional part

The dimensional part of GPS system is comprised by constellation of dimensional GPS satellite. GPS satellite constellation plans formerly is the orbit plane that distributings 24 satellites differ in 6 equably go up, and development arrives today, the satellitic amount that runs on orbit has achieved 27. Every orbit plane and equatorial and planar dip about 55 degrees. On the earth any places allow when to be engraved can observation arrives 5 - 8 satellites. Every satellite uses two L carrier frequency deferent signal, namely L1 (1575.42MHz) with L2 (1227.26MHz) . Every satellite conveys on identical frequency signal, but the signal of every satellite passed Duopule to move quite before reaching an user. L1 bears the weight of nicety (P) code and thick / capture (C / A) code, l2 bears the weight of only P code. The datagram article overlay of navigation is on these codes, bearing the weight of on two carrier frequency same navigation data message. P code is to add normally close, only code of C / A can be offerred civil.
Previous12 Next

About us | Legal Notices | Sitemap | Links | Partner