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RINEX format is a result of an effort to standardize exchanging GNSS related data in human readable receiver independent format. Besides observation data, RINEX is also de facto standard for exchanging navigation message or meteorological data. The paper describes simple compression methods for navigation messages and meteorological data files. Both formats have their specific features, therefore different methods were used. Followed by standard compression the algorithms reduce the file size by more than 20 percent compared to standard compression. Thanks to the properties of weather and regular parameter observations it allows to reduce the file size of meteorological RINEX to a mere fraction of its original size. [ABSTRACT FROM AUTHOR]

Presently, the global positioning system (GPS) satellite constellation consists of 40% older Block IIA and IIR space vehicles and 60% newer IIR-M and IIF satellites. Only newer GPS satellites are capable of transmitting the L2C signal which is in quadrature to the legacy L2P(Y) signal being broadcast by all satellites. The data format RINEX-2 is not prepared to contain carrier phase observations of both L2 signals, but should contain either one or the other. If a mix of unaligned L2P(Y) and L2C carrier phase observations are stored in a RINEX-2 file, the quarter cycle bias causes the file to be defective and not usable for precise positioning purposes. Algorithms that detect such files are presented in this study. They are mainly based on the analysis of widelane fractional ambiguities and were applied to RINEX-2 files of 2624 reference stations. Seventy-two station files (2.7%) were found to be defective since they contained mixed and unaligned L2P(Y) and L2C carrier phase observations. If such files are used for precise positioning with ambiguities being fixed to integer values, resulting coordinate errors in long baselines can reach centimeter levels. Unaligned L2 observations often prevent ambiguity fixing, especially in short baselines. [ABSTRACT FROM AUTHOR]