Can you explain what you want in more detail? Do you want a report of dates falling in a given broadcast week or ???
You can use the dayofweek function to compute the date of the first and last days of a given broadcase week, but I don't know what you want to do with those dates once we've produced them.
If ( DayOfWeek ( DateField ) = 1 ; Datefield - 6 ; DateField - DayOfWeek ( DateField ) + 2 )
will compute the week start date for any date in datefield falling in the same broadcast week.
StartDate + 6
will then compute the end date of this interval.