In SCPC-DAMA satellite networks, the baseband RRC pulse shaping is utilized to reduce the bandwidth and Inter Symbol Interference (ISI). But the variation in carrier's envelope, which expands the spectrum and ultimately increases the bandwidth, causes ISI and Quadrature Channel Crosstalk (QCC). The goal of this paper is to introduce a method to shape baseband RRC pulses, in order to make a nearly constant carrier envelope. We have introduced and implemented an algorithm to limit the amplitude variation of each pulse to generate constant amplitude RRC pulses at the input of modulator. Matlab simulation and hardware experiments show that OQPSK modulation and this pulse shaping method, can improve BER about 2dB.