3.3 Uncoded Performance of BPSK with SQRC

In this simulation first we applied the SQRC to the BPSK modulation. The SQRC filter is implemented using the FIR filter given the objective of this project. It was found that number of coefficients of the FIR filter affects the performance of the system. We did multiple simulation to find the minimum number of coefficient such that the loss did not exceed 0.5db
at 10^-5 BER. We found these number of coefficients to be 25. The following figure shows the plot of the SQRC with 25 coefficients.

                                                   Fig 3.3: Square root raised cosine filter

The performance curve of BPSK system after applying the FIR filter is shown in figure. It can be observed that the loss at BER of 10^-5 is less than 0.5dB.

Fig 3.4: BPSK with SQRC

3.4 Uncoded Performance of QPSK with SQRC

The filter obtained for BPSK simulation is used to evaluate the performance of QPSK. For QPSK system, the lossat BER of 10^-5 is same as BPSK. The following figure shows the performance of QPSK system after applying the SQRC filter.

Fig 3.5: QPSK with SQRC

3.5 8QAM with SQRC

However, the performance of BPSK and QPSK was same after applying the SQRC filter. But when the same filter was applied to the 8 QAM system it was noticed that the loss at BER of 10^-5 exceeded to 1.5dB.

Fig 3.6: 8QAM with SQRC