ffsReader

Import far-field data from Far-Field Source files

Since R2026a

Syntax

mAnt = ffsReader(filename)

mAnt = ffsReader(___,Name=Value)

Description

mAnt = ffsReader(filename) searches the current directory for all the CST Studio Suite^®® FFS files (.ffs) whose name starts with the filename specified in filename, reads far-field data from these files, and returns a measuredAntenna object with its properties set using data from the files. Each file represents one antenna port.

You can import single-frequency as well as broadband far-field data using this function. If you are using this measuredAntenna object as an antenna source in the Antenna (RF Blockset) block, you must scale its electric and embedded electric fields using the scaleEField function beforehand.

mAnt = ffsReader(___,Name=Value) imports only a subset of data filtered using one or more name-value arguments.

Examples

Import Electric Field Data from FFS Files

This example does not provide sample data and the file names used are for illustration purpose. Use this workflow with your field data.

Change the working directory to the directory containing your FFS and S-parameter data files. Specify the file name and import the broadband pattern data for two antenna ports using the ffsReader function.

mAnt = ffsReader("broadband_source",PortList=[1:2],SparametersFile="sparameter_data.s8p")

broadband_source_[1].ffs

broadband_source_[2].ffs

mAnt = 
  measuredAntenna with properties:

                       E: []
             Directivity: []
               Direction: [16471×3 double]
             PhaseCenter: [0 0 0]
                NumPorts: 2
          FieldFrequency: [7×1 double]
         FieldCoordinate: 'polar'
                 Azimuth: [0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 100 102 104 106 108 110 112 114 116 118 120 122 124 126 128 130 … ] (1×181 double)
               Elevation: [-90 -88 -86 -84 -82 -80 -78 -76 -74 -72 -70 -68 -66 -64 -62 -60 -58 -56 -54 -52 -50 -48 -46 -44 -42 -40 -38 -36 -34 -32 -30 -28 -26 -24 -22 -20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 16 18 20 22 24 … ] (1×91 double)
             Sparameters: [1×1 sparameters]
          AmplitudeTaper: 1
              PhaseShift: 0
               EmbeddedE: [16471×3×2×7 double]
    TerminationImpedance: 1.0000e-12
     CalculateTotalField: 1

To import single-frequency source pattern data, specify the target frequencies using the FrequencyList property. Import the pattern data for 26.5 and 27 GHz.

mAnt = ffsReader("single_freq_source",PortList=[1:2],FrequencyList=[26.5e9 27e9],SparametersFile="sparameter_data.s8p")

single_freq_source_(f=26.5)_[1].ffs

single_freq_source_(f=27)_[1].ffs

single_freq_source_(f=26.5)_[2].ffs

single_freq_source_(f=27)_[2].ffs

mAnt = 
  measuredAntenna with properties:

                       E: []
             Directivity: []
               Direction: [16471×3 double]
             PhaseCenter: [0 0 0]
                NumPorts: 2
          FieldFrequency: [2×1 double]
         FieldCoordinate: 'polar'
                 Azimuth: [0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 100 102 104 106 108 110 112 114 116 118 120 122 124 126 128 130 … ] (1×181 double)
               Elevation: [-90 -88 -86 -84 -82 -80 -78 -76 -74 -72 -70 -68 -66 -64 -62 -60 -58 -56 -54 -52 -50 -48 -46 -44 -42 -40 -38 -36 -34 -32 -30 -28 -26 -24 -22 -20 -18 -16 -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 16 18 20 22 24 … ] (1×91 double)
             Sparameters: [1×1 sparameters]
          AmplitudeTaper: 1
              PhaseShift: 0
               EmbeddedE: [16471×3×2×2 double]
    TerminationImpedance: 1.0000e-12
     CalculateTotalField: 1

Input Arguments

filename — File name

scalar string | character vector

File name, specified as a string or character vector. filename can include a path and file extension. For the antenna array data, the filenames must include a port number in square brackets at the end.

On Microsoft^® Windows^® systems, you can use either forward slashes (/) or backslashes (\) as path delimiters, even within the same file name. On UNIX^® and Macintosh systems, use only a / as a delimiter.

To specify a folder name only, add a trailing delimiter to the filename.

The filename argument does not support internet URLs.

Example: "broadband_source"

Example: "Broadband data/"

Data Types: string | char

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Example: PortList=[1:4]

PortList — Port numbers to import data

[] (default) | positive integer scalar | positive integer vector

Port numbers to import data, specified as an integer scalar or vector.

Example: [1:4]

Data Types: double

FrequencyList — Frequencies to import data

[] (default) | positive scalar | positive vector

Frequencies to import data, specified as a numeric scalar for a single frequency or a vector for multiple frequencies.

Example: [26.5e9 27e9 27.5e9 28e9]

Data Types: double

SparametersFile — Touchstone file storing S-parameters

scalar string

Touchstone file storing S-parameters, specified as a string containing the filename.

Example: "Full simulation.s8p"

Data Types: string

Output Arguments

mAnt — Imported far-field data

measuredAntenna object

Imported far-field data, returned as a measuredAntenna object.

Version History

Introduced in R2026a