Abstract: FilterprocessingisbeneficialtoimprovethequalityofreceivedsignalandthemeasuringperformanceofTT&Csystem.Ade-noisealgorithmusingShiftedUn-decimatedWaveletPacketTransform(SUWPT)wasmodified.InsteadofEnergyCompactionMeasure(ECM),thePowerFlatness(PF)wasusedinthenewalgorithmastheruletodecidewhetheranodewasneededtodecompose,andthedisadvantagesoftheoriginalones,suchasabortdecompositionbecauseofmisjudgmentorcomplexitybecauseofmanytimesdecompositionwereovercome.Meanwhile,theproblemthatthethresholdwashardtodeterminewasalsosolved.Simulationresultsshowthatcomparedwiththeoriginalalgorithm,themodifiedonehasabetterperformancewithlesscomplexity.Finally,thesimulationsignalandin-orbitsatellitedatawasprocessedwiththemodifiedalgorithm.Resultsshowthattheaccuracyofthedifferencephaseofthesimulationsignalisimprovedbyabout3timesandtheaccuracyofthein-orbitsatellitedataisimprovedby0.72times.

Key words: Telemetry,tracking &, commandsignal, Un-decimatedwaveletpackettransform, Powerflatness, SNRimprovement, Cross-correlationcoefficient, Differencephase, Spacetelemetrytracking&command