source:truck tracking webfleet solutions release time:2022-08-18 Hits: Popular:realtime gps tracker online
At present, the GPS receiver circuit in practical application is generally composed of four parts: antenna unit, radio frequency unit, communication unit and calculation unit. Based on the analysis of the composition of GPS satellite signals, this paper gives the principle and application of the radio frequency front-end GP2010.
1. Composition of GPS satellite signals
The GPS satellite signal is synthesized by typical code division multiple access (CDMA) modulation technology, and its complete signal mainly includes three components: carrier, pseudo-random code and data code. The signal carrier is in the L-band, and the center frequencies of the two carriers are denoted as L1 and L2, respectively. The satellite signal reference clock frequency f0 is 10.23MHz, and the center frequency of the signal carrier L1 is 154 times the frequency of f0, namely:
fL1=154×f0=1575.42MHz (1)
Its wavelength λ1=19.03cm; the center frequency of the signal carrier L2 is 120 times the frequency of f0, namely:
fL2=120×f0=1227.60MHz (2)
2. Analysis of GPS Antenna Principle
Its wavelength λ2=24.42cm. The frequency difference between the two carriers is 347.82MHz, which is about 28.3% of L2. The carrier frequency is selected in this way to measure or eliminate the propagation delay error caused by the ionospheric effect when the navigation signal propagates from the GPS satellite to the receiver. Pseudo-random noise code (PRN), that is, ranging code, mainly includes two kinds of fine ranging code (P code) and coarse ranging code (C/A code). The code rate of the P code is 10.23MHz, and the code rate of the C/A code is 1.023MHz. The data code is the navigation and positioning data sent by the GPS satellite to the user receiver in binary form. It is also called the navigation message or D code. It mainly includes satellite calendar, satellite clock correction, ionospheric delay correction, working status information, and C/A code conversion. To capture the information of the P code and the general ephemeris of all satellites; the total message consists of 1500 bits, divided into 5 subframes, each subframe transmits 10 words within 6s, each word 30 bits, a total of 300 bits, so the data The baud rate of the code is 50bps.
Read recommendations:
van tracker webfleet solutions
Last article:Handheld GPS Device
Next article:GPS helps you avoid electronic eyes
Related Information
Cantrack TK100
2023-04-11GPS Tracker Solution
2023-04-11real-time gps tracking custom
2023-04-23gps tracker for kids Vendor
2023-04-23gps tracker für auto supplier
2023-04-23Best hidden gps trackers
2023-03-16fleet gps tracking wholesale
2023-04-23mini gps tracker Factory
2023-04-23OBD GPS Tracker distributors
2023-04-23Cantrack GT06
2023-04-23TK08AL- RFID Car GPS Tracker
2023-10-07GF70L-Solar Magnetic Asset GPS Tracker
2023-10-07G500L -4G OBD GPS Tracker
2022-09-06TK103B
2022-06-20G02M Pet Tracker
2022-06-19Introduction and Comparison of GPS PPS Technology and Other Clock Synchronization Technologies
2022-11-11Navigation innovation application Beidou plans to launch satellite positioning watch
2022-08-10What is the GPS program of Gully?
2023-02-11The development of electronic maps.personal gps tracker Manufacturing
2023-05-17GPS navigator component-global positioning system
2023-05-16Advantages of traditional GPS and new technology GPS solutions
2022-10-15Compared to the advantages of GPS car navigation and mobile phone navigation.GPS Tracker for vehicle
2023-05-09Does the GPS positioner help the battery car anti -theft?vehicle gps tracker webfleet solutions
2023-03-08Bluetooth GPS.Gps speed limiter wholesaler
2023-07-05Compared with the difference between Beidou positioning and GPS positioning.gps tracker for trailer
2023-06-17Theoretical Basis of GPS Vehicle Satellite Positioning
2022-08-24Why do the antennas need to be facing up when installing a GPS tracker?
2022-09-08Installation Instructions for GPS Host Wire.portable gps tracker distributors
2023-08-02GPS guidance (Bearing)
2022-11-23Introduce the different types of the positioner
2023-03-07