ation ▁to ▁sample ▁it ▁at ▁the ▁same ▁frequencies ▁as ▁the ▁blue ▁graph . ▁ ▁A ▁list ▁of ▁window ▁functions ▁▁ ▁Con vent ions : ▁▁ ▁is ▁a ▁zero - phase ▁function ▁( sym met rical ▁about ▁x = 0 ), ▁continuous ▁for ▁ ▁where ▁N ▁is ▁a ▁positive ▁integer ▁( even ▁or ▁odd ). ▁ ▁The ▁sequence ▁    ▁is ▁symmetric , ▁of ▁length ▁▁ ▁  ▁is ▁asym metric , ▁of ▁length ▁▁ ▁The ▁parameter ▁B ▁displayed ▁on ▁each ▁spectral ▁plot ▁is ▁the ▁function ' s ▁noise ▁equivalent ▁band width ▁metric , ▁in ▁units ▁of ▁D FT ▁b ins . ▁ ▁Rect angular ▁window ▁▁ ▁The ▁rect angular ▁window ▁( s ometimes ▁known ▁as ▁the ▁box car ▁or ▁Dir ich let ▁window ) ▁is ▁the ▁simplest ▁window , ▁equivalent ▁to ▁replacing ▁all ▁but ▁N ▁values ▁of ▁a ▁data ▁sequence ▁by ▁zeros , ▁making ▁it ▁appear ▁as ▁though ▁the ▁wave form ▁suddenly ▁turns ▁on ▁and ▁off : ▁ ▁Other ▁windows ▁are ▁designed ▁to ▁moder ate ▁these ▁sudden ▁changes , ▁which ▁reduces ▁scal lop ing ▁loss ▁and ▁impro ves ▁dynamic ▁range , ▁as ▁described ▁above ▁( ). ▁ ▁The ▁rect angular ▁window ▁is ▁the ▁ 1 st ▁order ▁B - spl ine ▁window ▁as ▁well ▁as ▁the ▁ 0 th ▁power ▁Power - of - s ine ▁window . ▁ ▁B - spl ine ▁windows ▁▁ ▁B - spl ine ▁windows ▁can ▁be ▁obtained ▁as ▁k - fold ▁convolution s ▁of ▁the ▁rect angular ▁window . ▁They ▁include ▁the ▁rect angular ▁window ▁itself ▁( k