Research On The Key Techniques Of The Baseband Designing Of Beidou/GPS Dual-systems Navigation Receiver

In recent years,with the rapid development of every large navigation system,the process of compatibility and interoperability among multiple systems has been deeply investigated and widely used in military,mapping,communications,remote sensing,marine,space guide and other military and civil fields,since it has more accurate,stable,reliable,continuous positioning performance,also it can achieve better all-weather and automation target by multi-system cooperating.Recently,GPS,the most developed navigation system,has spread its signal scope from L1 C/A to multi-types,included L5,L1C and so on,the modulation,the broadcast type and content design of navigation bit have been changed as well.Secondly,since our country's Beidou satellite system is developing and improving at a very high speed,making research on the compatible and interoperable type of navigation receiver,include Beidou and GPS system with newly developed signals,will be the difficulty and hot point of our country's satellite application career.This paper mainly studies on the points mentioned above,analyzes the acquisition and tracking algorithms of new signals,sets the module of double system information processing,verifies the related theories and algorithms by doing series of software simulations and tests.This paper achieves a list of innovative outcomes,covers both theoretical studies and real applications.The main contributions are listed below:(1)Make research on the modulation type and signal consist of newly developed signals of Beidou and GPS,mainly includes:Beidou B2 and GPS L5,design apposite acquisition and tracking algorithms for these signals modulated by.AltBOC or QPSK,the algorithms include data and,pilot channel combined acquisition and tracking algorithm.Focus on the analysis and comparison of the acquisition and tracking performance resulted by single and double channels;(2)Aim to the increase of satellites offered by multiple systems,this paper studies on the advantages and disadvantages of.traditional satellites choosing algorithms,figures out the error factors that affect the positioning performance,then proposes a new satellite choosing algorithm based on both GDOP and C/NO.Experiments show that:the algorithm proposed by this paper can choose the satellite combination with very low GDOP value rapidly from many' visible satellites,but also it can afford enough high C/NO value,after taking into account these two aspects,the new algorithm can offer the,highest positioning accuracy;(3)Investigate on the techniques needed in processing interoperable information of double systems,include:space and time coordinate conversion of different systems,the elimination of ionospheric error using the information of dual frequencies,the method of position solution in the situation of multiple systems exist and so on.This paper proposes a new method dealing with the position solution,here uses the combination of double positioning results of the two systems,makes related simulations and tests of both the new method and the traditional one,analyze the performance in the end.