The pulse code digitization and companding on a signal Essay example --

AIM The main aim of this project is to set up the pulse code digitization and companding on a emblem and to exert the effects of sampling depths and companding on the signal to noise ratio (SQR).presentationPCM- In the pulse code modulation (PCM), the signal is a digitally represented analog signal in which the signal magnitude is sampled with identical intervals. Each sample is quantized to the closest value of the digital signal. In the pulse code modulation, the signal is binary. The two possible states represented in PCM be logic 1(high) and logic 0 (low). The main advantage of PCM signal is that it is derived from analog signal which is multiplexed with selective information from the computer and carried over a commonplace high-speed channel.COMPANDING- The combination of compressing and expanding is known as companding. In companding, the data is compressed before it is sent and then expanded at the receiving set aside using the same non-linear scale. The noise and cross talk levels at the receiver are reduced due to companding. It is used in wireless microphones for better moral force range and also in digital and telephony systems for compressing of the remark signal and expanding of the output signal. The below figure 1 shows the demonstration of PCM with and without companding. Figure1- PCM with and without companding result to create PCM and companding on excel sheetThe PCM and companding of a signal is do on a spreadsheet using excel. Firstly, a sine wave is created by varying the time with respect to the amplitude. The frequency of the signal is taken as 10 Hz. The quantization process of the signal will be done. A quantized sine wave is then created. Now the number of levels electric cell (N) should be created. We take the value ... ...ude=0.1, large N=8. GRAPH I) spot of SQR vs Amplitude with Companding (mu=255) and without Companding (mu=0). GRAPH J) Plot of SQR vs bit depth both with Companding (mu=255) and without Companding (mu=0 ). Where A=1, and bit depths are 2, 4, 8, 16, 32, 64, 128, 256. CONCLUSION This lab was carried out to compand and quantizes a vowelize signal. We In the Using the pulse modulation technique, the analog signal is converted into the digital signal. The process of quantization and companding of a signal is carried on the spreadsheets. To learn a clear signal to quantization noise ratio, the number of samples should be increased. By increasing the sampling depth, the quantization error can be minimized. By companding process, the quantization noise and distortion levels can be minimized. Companding improves receipt for low amplitude signals.