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vpmanager.createantresp - Function

2.3.2 Create a standard-format AntennaResponses table


Description

The AntennaResponses table serves CASA to look up the location of images describing the response of observatory antennas. Three types of images are supported: ”VP” - real voltage patterns, ”AIF” - complex aperture illumination patterns, ”EFP” - complex electric field patterns. For each image, a validity range can be defined in Azimuth, Elevation, and Frequency. Furthermore, an antenna type (for heterogeneous arrays), a receiver type (for the case of several receivers on the same antenna having overlapping frequency bands), and a beam number (for the case of multiple beams per antenna) are associated with each response image.

The images need to be stored in a single directory DIR of arbitrary name and need to have file names following the pattern

obsname_beamnum_anttype_rectype_azmin_aznom_azmax_elmin_elnom_elmax_freqmin_freqnom_freqmax_frequnit_comment_functype.im

where the individual name elements mean the following (none of the elements may contain the space character, but they may be empty strings if they are not numerical values):

obsname
- name of the observatory as in the Observatories table, e.g. ”ALMA”
beamnum
- the numerical beam number (integer) for the case of multiple beams, e.g. 0
anttype
- name of the antenna type, e.g. ”DV”
rectype
- name of the receiver type, e.g. ””
azmin, aznom, azmax
- numerical value (degrees) of the minimal, the nominal, and the maximal Azimuth where this response is valid, e.g. ”-10.5_0._10.5”
elmin, elnom, elmax
- numerical value (degrees) of the minimal, the nominal, and the maximal Elevation where this response is valid, e.g. ”10._45._80.”
freqmin, freqnom, freqmax
- numerical value (degrees) of the minimal, the nominal, and the maximal Frequency (in units of frequnit) where this response is valid, e.g. ”84._100._116.”
frequnit
- the unit of the previous three frequencies, e.g. ”GHz”
comment
- any string containing only characters permitted in file names and not empty space
functype
- the type of the image as defined above (”VP”, ”AIF”, or ”EFP”)

The createantresp method will then extract the parameters from all the images in DIR and create the lookup table in the same directory.

Arguments





Inputs

imdir

Path to the directory containing the response images

allowed:

string

Default:

starttime

Time from which onwards the response is valid, format YYYY/MM/DD/hh:mm:ss

allowed:

string

Default:

bandnames

List containing the names of the observatory’s frequency bands

allowed:

stringArray

Default:

bandminfreq

List containing the lower edges of the observatory’s frequency bands, e.g. [”80GHz”,”120GHz”]

allowed:

stringArray

Default:

bandmaxfreq

List containing the upper edges of the observatory’s frequency bands, e.g. [”120GHz”,”180GHz”]

allowed:

stringArray

Default:

Returns
bool
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