Which spectral window is associated with this one. For double sideband receivers (DSB), spectral windows are defined as a pair due to the nature of sideband separation. If SideBandSeparationMode is PHASE_SWITCH_SEPARATION, then we must pay attention to which spectral windows comprise a pair. The OT has 2 options, either associate a pair of spectral windows, e.g., 1 & 2, or suppress one of the spectral windows in the pair. Currently it's TBD how this suppression is specified, either by not including the 'other' spectral window or by setting a flag. If SideBandSeparationMode is not PHASE_SWITCH_SEPARATION, then this value is 0 (ignored)

General Info
Name	associatedSpectralWindowNumberInPair
Type	Integer
Visibility	private
Default Value	0
Owner	AbstractSpectralWindow
Is Read Only	false
Is Static	false
Aggregation	none
Is Derived	false