EXP_4_OAM_OSM

Linear Filtering techniques of Overlap Add Method (OAM) and Overlap Save Method (OSM) were used on DSP Board.

They both allows us to calculate the convolution of very long sequences. Overlap add involves adding seeveral values in the output to recover the final signal, whereas overlap save does not require any addition in this step. This might be important if you want to consider the numerical precision of your output, or if you want to reduce the number of addition operations.

EXP_5_LEDBINARYCOUNTER

This lab was pretty simple as we had to use the GPIO pins of the DSP Board to show a LED binary counter. The main takeaway from this session was the introduction to flash programming as the detachment of JTAG connector did not affect the binary counter. This was further made concrete with the fact that the board was given a supply with an adapter and the program still worked on the board.

EXP_6_ADCDAC

We studied about ADCs and DACs on the DSP board. The various protocols which need to be followed for the usage of ADC and DAC were studied along with the calling procedures for them. This was made concrete after Dr. Rao Sir's lecture on the same. In simple terms, the processes that allow digital computers to interact with these everyday signals is what this session was all about. Various waveforms were observed on DSO which verified the working of ADC and DAC on DSP Board.

Simulator

In this lab, we carried out different digital modulation techniques like BPSK, DPSK and QPSK using CCS simulator. BPSK conveys data by changing, or modulating, two different phases of a reference signal. In DPSK, there is no absolute carrier phase reference, instead transmitted signal is itself used as phase reference. In QPSK two bits are modulated at once, selecting one of four possible carrier phase shifts.

Overall Learning Experience

This semester we had Signal Processing lab for which the prerequisite was Signals and Systems. The codes in C language for convolution, correlation and other techniques were used on DSP board. These codes were provided and special emphasis was given on understanding the underlying process rather than understanding the complete code.

A new task was assigned in every session based  on the previous week's work. So this practice made all the students come over their difficulties and embrace their emphasis on skills. 

This lab was never really boring as there was always something new and interesting challenges were thrown towards us durig the experiments. A very important take-away is the importance of DSP board and its ability to become a stand-alone system. My experience for this lab under the expertise of Talele Sir was really interesting and informative and I can confidently say that DSP is one of the best courses offered as a lab.

Application of DSP

We found out the application of LDR in signal processing. We researched an invention and found its patent titled "Ambient light-dependent video-signal processing". (Patent No: 6229577) This method made the use of LDR for measurement of ambient light, the objective being better ambient light-dependent video-signal processing. Further indication of  a large amount of change in ambient light and the immediate processing of the video signal is also a vital objective for this method. This method is a very useful application in video signal processing.

EXP_7_Sensor Interfacing

This was the last experiment for this semester for DSP Lab. It was one the most intriguing sessions which was the most closely related to real life application. In this experiment we learnt to interface different types of sensors with the DSP board which included LDR, optocoupler, Hall sensor, audio sensor, temperature sensor. The input were taken from the different sensors as an analog input and by using ADC, their waveforms were observed on DSO. This demonstrated a great feature of the DSP board, it's ability to be a stand-alone system. Any one sensor can be implemented with the board and a stand-alone system can be made with it, which is pretty awesome in itself.