cycle - by - cycle synchronous waveform shaping is provided for by filtering and combining of square and / or impulse shaped signals . specifically , a plurality of first square shaped signals is generated and filtered using at least one first filter to produce at least one filtered signal . a plurality of second square shaped signals is generated and filtered using at least one second filter to produce at least one second filtered signal . the at least one first and at least one second filtered signals are combined to produce a continuous shaped waveform having a characteristic shape within each of a plurality of data periods defining a data rate . alternatively , at least one impulse signal having a plurality of sinusoidal impulses each comprising a positive impulse and a negative impulse is generated . the at least one impulse signal is filtered using at least one filter to produce the continuous shaped waveform .