DSP Processor-Paper review

This experiment was performed by a group of 5 people namely-Shrinish Donde,Vaibhavi Dichwalkar,Saish Desai,Tanvi Joshi,Ninad Chitnis and Akash Bangera.

MORSE CODE GENERATOR USING THE TMS320X Series BOARD DSP.


Our task was to make a Morse decoder on the TMS320X series .The flow was to Sample input signal followed by segmenting followed by multiplication with hamming window function further followed by squaring the obtained FFT value for the spectral power and in the end thresholding which is needed to separate the dots and dashes from the unwanted components.The output was taken via the VGA port available on the board .In order to discern multiple Morse signals within an audio signal, we need an adequate frequency resolution, in our case at least 100Hz. Based on this fact, we have chosen the sequence length of N = 256 samples and the sampling frequency of fs = 22.05kHz.For the calculation of the spectogram, we use the famous Cooley-Tukey FFT algorithm with decimation in frequency.The TMS320X DSP development kit contains all the necessary hardware for the Morse decoder. The input audio signal with the voltage up to 1VRMS arrives at one of the channels of the audio input. It is digitized by the on-board TLV320AIC3106 sigma-delta audio codec connected to the DSP TMS320X via its Multichannel Audio Serial Port (McASP).Thus a morse decoder was implemented succesufully from a TMS board of DSP.Its application include Navy,military and sending encrypted messages across for personal use and defence.


Location: India

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