基于质量树的GPS电文质量评估方法

Evaluation Method for Quality of GPS Message Based on Qulaity Tree

摘要:

从导航电文中及时、准确地计算出电文参数,是导航接收机的核心功能,不同电文参数解算软件由于设计差异,解算电文参数质量也存在差异,电文数据质量也会影响电文参数结果；针对此问题,在传统数据质量模型的基础上,引入质量树分析方法,建立了评估导航电文质量的质量树模型；模型从电文完整性、电文一致性、电文正确性以及电文时效性等4个特性出发,每个质量特性均建立了专属子特性,以及量化子特性的数据指标；在此基础上,以GPS电文质量评估为例,开发了GPS电文质量评估软件,采用GPS接收机的实测数据对模型和软件进行了验证；结果表明,该软件能够发现GPS电文的异常数据,包括数据不完整、数据不一致、数据不正确、数据超时等,处理结果可用于改进电文参数解算算法,提高电文参数解算软件的可靠性。

Abstract:

It is the core function of navigation receiver to calculating message parameters in time and accurately from navigation message. The software quality of message parameters solved isn’t identical because design is different. Also, the results of parameters are under influence of message’s quality. According to the problem, the analysis method of quality tree is introduced based on traditional quality model of data, the quality tree model of evaluating the quality of navigation message is established. The model is described by four characteristics:integrity, consistency, correctness and timeliness. Each characteristic has more sub-characteristics, and a sub-characteristic is quantified by data indexes. Further more, the software is developed which is evaluating the quality of navigation message with GPS as example. The model and the software are verified by measured data from receiver of GPS. The results show that this software could discover the unusual data of GPS message, including the imperfection, inconsistency, incorrect and timeout of the data. The result can be used to improve message parameters solver algorithm, and increase the reliability of message parameters solver software.