GPS Receiver Technology Research Trajectory Assisted Missile

Rockets has many features, such as low cost, long range, strong flexibility and powerfulfire extermination, But the problem is that its accuracy always not high. Global satellitesnavigation and positioning system can provide high precision real-time navigation andpositioning all-weather and all-time, which provides a new way to solve the problem ofconventional ammunition’s accurate technology. With the rapid development of the futurewar situation, Precision attacking weapon has become the mainstream of modern weaponsand equipment development. At present, the key-technology of GPS products almost dependon imports, and Beidou Navigation Satellite System, also known as BD-2, which researchedand developed by our country, will operate in the near future. So, In order to get rid of theforeign technology restriction and accumulate technical experience of gun-borne BD-2receiver, it has great significance in research the key technology of GPS.In the starting chapters of this thesis, the development of satellite navigation system andGPS system overview was described. Following this, this paper represents the positioningprinciple and signal characteristics of GPS. Analysis the structure and working principles ofGPS receiver, introduces the performance requirements of gun-borne GPS receiver workingunder missile-borne circumstance. Then, the researching and realizing of baseband signalprocessing are emphatically expatiated.GPS receiver when working under the missile environment must have some properties,such as ability to quickly capture GPS signal, high overload resistance, small size, low costand other requirements. According to these requirements, in this article, ballistic solution isproposed regarded as ancillary to GPS signal quickly capture algorithm. With this algorithm,on the basis of unify different geodetic reference systems. the Doppler frequency shiftbetween GPS satellite stars and projectiles visible can be quickly estimated and compensated.Finally, fast acquisition is implemented. On hardware, GPS receiver is completed on FPGAand DSP platform, which constructs digital correlation and decrease the calculated quantity ofDSP, realizes small size and fast acquisition in the meantime. In addition, from selection ofeach electrical part to the whole process of the PCB design, a series of methods to enhanceoverload and reduce the signal from reflection interference are adopted. Finally, The design and realization of digital correlation channels are discussed withQuartus Ⅱ as development tools, the whole design has been simulated using simulation-tool,and Simulating results indicate that this system meets the design requirements.