PENGEMBANGAN SISTEM DELTA MODULATION KE PEMODELAN SIGNAL CONVERSION DELTA-SIGMA MODULATION

Abstrak

To establish the level of the digital pulse from an analog signal after conversion system, it is required a digitalmodulation system with fast and reliable bit rate in every bit build digital stream. Delta modulation is the commonlysufficient technique to produce a long bit stream with a relatively low bit rate. However, one of its weaknesses is thatanalog input signals as reference signals require a large offset frequency then obtaining small dynamic range so that theresulting noise shape has not maximal; when its sample of rate (SOR) is raised, the floor noise level cannot becontrolled. This research aims to study Delta Sigma Modulation concept that has been tested to suppress the noise floorand a good form noise shape while having a stable dynamic range. This basic research will emphasize the comparison ofthese two forms of digital modulation and their utilization in more effective for signal conversion systems. The resultsshow comparison of noise transfer function (NTF) mean of Delta-Sigma Modulation power spectrum decreased to 10dB below from Delta-Modulation. Validation of simulation results through frequency spectrum comparison shows thatDelta-Sigma Modulation has better noise shaping where noise floor can be easily nulled at position around the desireddata channel.