1. The document describes creating DSB-SC modulation and demodulation in MATLAB. A 1 kHz message signal is modulated with a 1 MHz carrier signal to perform DSB-SC modulation. 2. To demodulate the signal, it is multiplied with the carrier signal and passed through a low-pass filter to recover the original message signal. Several steps are outlined for both the modulation and demodulation processes. 3. Creating the communication system in MATLAB provided a learning experience and prototype for designing new signals and systems.