source:truck tracking webfleet solutions release time:2022-11-01 Hits: Popular:realtime gps tracker online
The first Space Segment mainly consists of 24 satellites operating in semi-synchronous orbit. The so-called semi-synchronous orbit means that it takes about 12 hours (11 hours and 58 minutes) for a satellite to operate a week, so the same satellite happens to appear on the head of a stationary user twice in a day (23 hours and 56 minutes). The 24 satellites are evenly distributed on 6 orbital planes with 4 satellites in each orbit, and each orbital plane has an inclination Angle of 55 degrees from the equator. The average orbital altitude of these satellites is about 20200Km
The ranging signal from the 24 satellites has two channels (D-Band), one is called L1, the transmission frequency is 1575.42MHz; The second is L2 with a transmission frequency of 1227.6MHz. These two carrier frequencies are responsible for transmitting the Spread Spectrum signal as a high frequency carrier. GPS uses spread-spectrum communication (Spread-spectrum) technology. ranging codes modulated by spread spectrum can be divided into two kinds: The first is 1.023MHz C/A codes (coarse/acquisition codes). As the name implies, the precision is coarse according to the code. Moreover, C/A codes are only modulated with L1 and are specially opened to general commercial users. The other ranging Codes are P codes (Precision Codes) of 10.23MHz, which are modulated on both L1 and L2 carriers. Due to the short Chip of P codes, more accurate positioning can be obtained. Both range codes can be used to measure the distance between the satellite and the receiver. However, usually P codes are also encrypted and only available to authorized users, so P codes are usually only used in military positioning systems, and because of these two different sets of codes, GPS is also divided into so-called Standard Positioning Service (SPS) and Precise Positioning Service (PPS). The standard positioning service uses only C/A codes on the L1 carrier. Besides C/A code on L1 carrier and P code on L1 and L2 carrier, the last and most important thing for precise positioning service is a 50Hz data information code. The data contained in this code includes the satellite timing data, the exact satellite orbit data (ephemeris), which contains the orbit data of the satellite transmitting the signal, and the almanac data, which contains the basic orbit data of all the satellites, as well as the ionospheric propagation correction of the signal.
The Control Segment is composed of the various ground control stations located in different locations. Its Master Control Station (MCS) is located in Colorado, USA, and the remaining stations are evenly distributed along the equator. The main task of these ground control stations is to monitor and control these satellites operating in space, its functions include satellite orbit control, satellite orbit data update, satellite itself maintenance and so on. The operation process of this system is that each sub-station receives the orbit data of its locked satellite, then transmits the data to the main control station through the Defense satellite communication system of the United States for the estimation and reprediction of the orbit data, and then uploads the new orbit data to each satellite through the ground antenna station.
The last Segment, the User Segment, is closely related to the general user segment. In fact, the so-called User Segment refers to the GPS receiver, which is the protagonist to be discussed in this paper. Its function is RF receiving, decoding and processing satellite orbit data, so as to calculate the position of the receiver.
Read recommendations:
GF30 Magnet GPS tracker with Voice listen
mini gps tracker.What are the differences between Beidou and GPS?
Last article:The traditional architecture of GPS
Next article:GPS Function Introduction
Related Information
GPS Tracking price
2023-04-11gps tracker for bike
2023-03-16gps vehicle tracker manufacturer
2023-04-11fleet gps tracking wholesaler
2023-04-23rastreador tracker
2023-03-16vehicle gps tracker wholesale
2023-04-23gps vehicle tracker Factory
2023-04-23Dog gps tracker
2023-04-23mini gps tracker
2023-04-11pet gps tracker cat wholesaler
2023-03-16G200NY -Cow/Camel GPS Tracker
2022-06-21G02M Pet Tracker
2022-06-19G900LS-4G Car GPS Tracker
2023-10-06G09L -6 inch Tail light tracker
2022-06-20TK100 (GT06) Vehicle Tracker
2022-06-20GPS development mode
2022-11-19GPS navigation solution
2022-12-10GPS active ranging and passive range.car gps tracker Solution
2023-04-19Application introduction in GPS Meteorology.obd2 gps tracker verizon Production
2023-05-06How to buy GPS positioner.obd2 gps tracker verizon
2023-03-14The development of GPS system
2022-10-12Shared bicycles require the installation of Beidou/GPS satellite positioning module.GPS Tracker
2023-09-22GPS RTK technology
2023-07-03GPS/GPRS power-off terminal
2022-12-20Several ways of GPS mobile phone positioning
2022-10-21Enhanced GPS Positioner Dual Camera Controller Interface Description.Car gps tracking
2023-09-23Beidou Satellite Positioner Function.metal spring buckle Factory
2023-06-06How to prevent the car positioning system from being destroyed.plug & play Obd gps tracker Solut
2023-05-09Causes of lithium battery explosion
2022-10-18Navigation editor introduces the usage method of driving recorder.gps tracker for kids supplier
2023-06-26