Studying And Analyzing the modulators and demodulators of PCM

Modulating signals of transmission stations to reception stations is a key factor to guarantee the best possible transmission and reception of these signals .Digital modulation represents a huge evolution in communication field and modulation, which used to depend on analog signal modulation of one parameter-Amplitude . frequency or phase. Digital modulation depends on transforming the transmitted data signal (Bits) and then sending it as samples, and changed back into an analog signals in reception station . In digital systems, digital data are transformed into analog data in the transmitter and does the reverse in the receiver. In digital transmission, on the other hand, as in wired local area networks (WLAN), Digital data are transmitted in their digital state.