The header section contains comments about the factors of the collection. The cal_add and cal_mult sections describe the calibration of the radar system for each sample. The azimuth is available at three nominal depression angles. The frequency and azimuth sections contain the frequency of the radar system and target orientation. The frequency domain contains the actual phase history data for the target. The data segments of the phase history CDF files include: frequency_domain (phase history), frequency, azimuth, cal_add, cal_mult, header, and channel. The header data can be accessed with an inquiry from Matlab using the mexcdf routine described later. The native header of the CDF file contains all the necessary information to access the data segments of the file. The CDF file format is useful due to the fact that it contains several data groups of different data types and dimensions. The data is also available in phase history blocks that include sections of the available phase history accessible by Matlab. There is a Phoenix version of the data available that can be accessed with the normal Phoenix tools. The original data is stored in a CDF file that is available and accessible with mexcdf routines for Matlab. Ī probable cause for the error in MATLAB CDFLIB functions comes from the TT2000 datatype that is used for the epoch variable in MAVEN files.GTRI Turntable Phase History data is available in several different formats. With SPDF version of CDF routines you would get the correct output: > mvninfo = spdfcdfinfo('mvn_lpw_l2_lpnt_20180814_v03_r02.cdf')įilename: 'mvn_lpw_l2_lpnt_20180814_v03_r02.cdf'Īnd spdfcdfread returns the data as a MATLAB array > mvndata = spdfcdfread('mvn_lpw_l2_lpnt_20180814_v03_r02.cdf')

With MATLAB provided CDFLIB running on MATLAB 2017a (9.2.0) you get > cdfinfo('mvn_lpw_l2_lpnt_20180814_v03_r02.cdf') The version of cdflib that comes with MATLAB does not support some of the features used in MAVEN files. The Installation instructions are fairly straightforward and there is little that can be added to it.

This version of the library is provided for free and can be downloaded directly from SPDF. To read the data from NASA Space Physics Data Facility (SPDF) you are encouraged to use the CDF handling library from SPDF.

Read cdf files in matlab