This experiment is UPSK modulation. The next new experiment is QPSK modulation. QPSK is Quadrature Phase Shifting.
UPSK is Quadrature Phase Shift Key. It is a 4-array PSK modulation. It is a 400 PSK modulation.
For a 4-array PSK modulation, For a 400 PSK modulation we have to take two bits together. we have to take two bits together. And for that, And for that first hand take to that 8 bits. first I am taking 8 bits. The student's road number can be taken as input bits.
The students'road number can be taken as input bits. In the example I took 00, In the example I took 00, 01, 11, 01, 11, 11. 11. This input bit should be converted into odd bit and even bit. These input bits should be converted into odd bits and even bits.
I just took in the number 0, Adjust even the number 0, 1, 1, 2. 2, 3, 4, 5, 6, 7. So 0, 1, 2, 2, 3, 4, 4, 5, 6, 6 are even bits, 7. So 0, 2, 4, 6 are even bits. 1, 1, 3, 3, 5, 5, 7 are odd bits. 7 are odd bits. This odd bit and even bits are just showing here with voltage plus 1 for 1 and minus 1 for 0. This odd bit and even bits are just showing here with voltage plus 1 for 1 and minus 1 for 0. This even bits are going to be multiplied with sin omega 0 t and odd bits are going to be multiplied with cos omega 0 t because we are using phase quadrature carrier for generating QPSK.
These even bits are going to be multiplied with the sine omega 0d and odd bits are going to be multiplied with the cos omega 0d because we are using phase quadrature carrier for the operating of the PSK. Even bits multiplied with the sine omega 0d and the product I am showing here is the sine omega 0d. Even bits multiplied with sin omega 0 t and the And the product I am showing here, it is minus 1, It is minus 1, that is why it is inverted sine wave, that is why it is inverted sine wave. minus 1, Minus 1, inverted sine wave, inverted sine wave. Plus 1, plus 1, same sine wave and plus 1, same sine wave.
And plus 1, same sine wave. same sine wave. Next, Next, what bit is multiplied with cos omega 0 t?
what it is multiplied with cos omega 0 t? First is 0, First is 0, that is minus 1. that is minus 1, Minus 1 is multiplied with cos omega 0 t, minus 1 is multiplied with cos omega 0 t, that is why minus cos. that is why minus cos. Next to 1, Next to 1, 1, 1, 1 is multiplied with cos, 1 is multiplied with cos, cos, cos, cos, cos.
The outputs are for sine wave. the outputs are cosine wave. This product is going to be added for generating QPSK waveform. This product is going to be added for generating first final QPSK wave.
So the QPSK waveform is... So the QPSK waveform is showing here and we can draw QPSK waveform using this diagram. showing here and we can draw qpsk waveform using this diagram the first combination is zero zero and for zero zero the starting point is minus root ps so start from minus root ps next combination is zero one for zero one the starting point is plus root ps so start from plus root ps next The first combination is and for the starting point is minus root PS. So start from minus root PS. Next combination is.
For the starting point is plus root PS. So start from plus root PS. Next combination is. combination is one one starting point is plus root ps so start from plus root ps from this very easily qpsk waveform we are able to draw Starting point is plus root PS. So start from plus root PS. Now this very easily.
UPSK waveform we are able to draw. next at every Next at every 2 bit interval there is a possibility of phase change that phase change we are able to write from here first combination is 0 0 next combination is 0 1 0 0 to 0 1 0 0 2 bit interval there is a possibility of phase change. That phase change we are able to write from here. First combination is 0, 0 next combination is 0, 1. 0, 0 to 0, 1. 0, 0 to 0, 1. the phase change is minus 90 degree due to clockwise direction so it is minus 90 degree next is 0 1 to 1 1 again minus 90 degree so this I am showing the phase constitution The phase change is minus 90 degree due to clockwise direction.
So it is minus 90 degree. Next is 0, 1 to 1, 1. Again minus 90 degree. So this I am showing the phase transfer.
This is the block diagram of QPSK generation. This is a block diagram of QPSK generation. The input bits are given to a serial input parallel output with clock period 2 TV seconds.
The input bits are given for serial input parallel output with clock period 2 TV second. Due to clock period 2 TV seconds, Due to clock period 2 TV second, we will get two parallel bits, we will get two parallel bits, even bits and odd bits. even bits and odd bits. The duration of each bit will become 2 TV second and The duration of each bit will become 2 TV seconds and the amplitudes are plus or minus 1 volt. the amplitudes are plus or minus 1 volt.
Even bits are multiplied with sin omega 0 t, Even if it is multiplied with sin omega 0 or if it is multiplied with cos omega 0, odd bits are multiplied with cos omega 0 t. addition of these two products will be the QPSK output. Addition of these two products will be the QPSK output.
Next, this will be the equation of QPSK. This would be the equation of QPSK. VQPSK T is equal to BQPSK is equal to... equal to BET root PS sin omega 0 t plus BET root PS and omega 0 T plus BOT root PS cos omega 0 t. BOT root PS cos omega 0 T.
Next we can verify what is the bandwidth requirement for QPSK transmission. Next we can verify what is the bandwidth requirement for QPSK transmission. Sin omega 0 T and cos omega 0 T having the same spectrum. Sin omega 0 t and cos omega 0 t having the same spectrum due to that reason there is only one main load and the duration of each bit will be 2 tb second that is 1 upon 2 tb that is FB by 2. Due to that reason there is only one main load. And the duration of each bit will be 2 TV second.
That is 1 upon 2 TV. That is FB by 2. That is why the main load existing. That is why the main load existing from F0 minus FB by 2 to F0 minus FB by 2 is equal to F0 minus FB by from F0 minus FB by 2 to F0 plus FB by 2. F0 plus FB by 2. So the bit of the main load is only FB hertz.
So the width of the main log is only FB hertz. That is why bandwidth is FB hertz. That is why bandwidth is FB hertz. From bandwidth spectral efficiency can be calculated bit rate upon bandwidth.
From bandwidth, spectral efficiency can be calculated. Bitrate upon bandwidth, That is FB upon FB. that is FB upon FB, That is one bit per second per hertz.
that is 1 bit per second per hertz. This shows 2 PSK detection log data. This shows QPSK detection block data.