1. Illustrate the wave forms for data “101001000111010011110100” by using
the following modulation techniques:
a. 2 bit AM + 1 bit PM
b. 2 bit FM + 1 bit AM
c. 2 bit PM + 1 bit FM
2. Based on 8 bit ASCII code, illustrate a wave form using any one of the
modulation techniques above to show the transmission of a string of data:
“data comm”
To illustrate waveforms for the given data using different modulation techniques, we need to understand the modulation techniques first and then apply them to the given data.
1. Modulation Techniques:
a. 2 bit AM (Amplitude Modulation) + 1 bit PM (Phase Modulation):
In 2 bit AM, the amplitude of the carrier wave is varied based on the data. In 1 bit PM, the phase of the carrier wave is varied based on the data.
b. 2 bit FM (Frequency Modulation) + 1 bit AM (Amplitude Modulation):
In 2 bit FM, the frequency of the carrier wave is varied based on the data. In 1 bit AM, the amplitude of the carrier wave is varied based on the data.
c. 2 bit PM (Phase Modulation) + 1 bit FM (Frequency Modulation):
In 2 bit PM, the phase of the carrier wave is varied based on the data. In 1 bit FM, the frequency of the carrier wave is varied based on the data.
2. To illustrate the waveforms for the given data "101001000111010011110100" using the above modulation techniques, we will create a graph where the x-axis represents time and the y-axis represents the amplitude, frequency, or phase of the carrier wave.
a. 2 bit AM + 1 bit PM:
- Divide the given data into two-bit chunks: "10", "10", "01", "00", "01", "11", "01", "00".
- For each two-bit chunk, vary the amplitude of the carrier wave accordingly.
- For the last remaining single bit, vary the phase of the carrier wave accordingly.
- Plot the graph with time on the x-axis and the amplitude or phase on the y-axis.
b. 2 bit FM + 1 bit AM:
- Divide the given data into two-bit chunks: "10", "10", "01", "00", "01", "11", "01", "00".
- For each two-bit chunk, vary the frequency of the carrier wave accordingly.
- For the last remaining single bit, vary the amplitude of the carrier wave accordingly.
- Plot the graph with time on the x-axis and the frequency or amplitude on the y-axis.
c. 2 bit PM + 1 bit FM:
- Divide the given data into two-bit chunks: "10", "10", "01", "00", "01", "11", "01", "00".
- For each two-bit chunk, vary the phase of the carrier wave accordingly.
- For the last remaining single bit, vary the frequency of the carrier wave accordingly.
- Plot the graph with time on the x-axis and the phase or frequency on the y-axis.
To illustrate the waveform for the string of data "data comm" using any one of the modulation techniques above, we need to convert the ASCII characters to their corresponding 8-bit binary code. Then we can follow the same steps as described above to vary the parameters of the carrier wave and plot the waveform.