The receiver for the Spread Spectrum communication system is designed to decode the message signal. The receiver correlates the spreaded signal with a unique PN sequence. If the PN sequence at the transmitter and receiver is the same then the correlated output has strong peaks. Selection of appropriate threshold level is also important to decode the signal correctly by comparing its peaks with a threshold level. Figure 1 shows the block diagram of a spread spectrum receiver.

Figure 1: Block diagram of Spread Spectrum receiver

In FlexTrainer, students can practically observe the implementation of spread spectrum receiver. The students can select threshold level and PN sequence for correct detection of received signal.

The questions at the end of this experiment encourage the students to select different data words and PN sequences. The students will understand the importance of selection of an appropriate threshold level to get the correct output signal.