Inthispaper,anewmodelbasedonanimprovedBrentKung(BK)parallelprefixnetwork(PPN)algorithmisproposedandrealizedinthefieldprogrammablegatearray(FPGA).Thismodelisemployedintheimplementationof20Gb/sdifferentialquadraturephase-shiftkeying(DQPSK)precoderin40Gb/spolarizationpisionmultiplex(PolDM)DQPSKsystem.Inthecomputationprocess,thecomputationcomplexity(area)optimizationwithfan-outlimitedisachieved.Intheimplementation,770FPGAsliceregistersareutilized,whichsaveabout60%logicresourcescomparedwiththepreviousKoggeStone(KS)algorithm.
