relative week filter

Here is one way. 

Based on this sample data

I created a dimension table for weeks including an index column which we will use to filter the visual with a measure:

Week Table =
ADDCOLUMNS (
    VALUES ( 'Table'[Week] ),
    "Index", RANKX ( VALUES ( 'Table'[Week] ), 'Table'[Week],, ASC )
)

 Create the following measure to add to the filters on the visual, settin the value to equals 1.

Filter weeks =
VAR _TodayWeek =
    YEAR ( TODAY () ) * 100
        + WEEKNUM ( TODAY () )
VAR _CurrWeekIndex =
    CALCULATE (
        MAX ( 'Week Table'[Index] ),
        FILTER ( ALL ( 'Week Table' ), 'Week Table'[Week] = _TodayWeek )
    )
RETURN
    COUNTROWS (
        FILTER (
            'Week Table',
            'Week Table'[Week] >= _TodayWeek
                && 'Week Table'[Index] <= _CurrWeekIndex + 20
        )
    )

 Sample PBIX file attached