Due to the constraint on the number of channels and phase bins, the
array of visibilities in each heap will have the same structure and
maximum dimensions as for the continuum and spectral line imaging mode.
5.1.1.7.
Quality attribute
characteristics
5.1.1.8. Rationale
and design issues
The SPEAD protocol has successfully been implemented in KAT7 and
MeerKAT. A Python implementation containing example applications can be
download from [RD8] and the FPGA implementation for MeerKAT is
available (from Jason Manley at SKA-SA).
The SPEAD-64-48 flavour was chosen in order to support 48bit immediate
values and is currently used in the MeerKAT implementation.
In general it’s prefered to use immediate addressing for the metadata
items as it’s simpler to implement in FGPAs and more efficient to decode
on the receiving end.
11: List of Item Names and their rationale