## 5 Simulation Experiment Analysis
### Communication Performance  
For the jamming distance gap (see Table 3), we calculated that \(\Delta\tau\) is 0.6667 \(\upmu\)s, and the maximum number of false targets, calculated from Equation (20), was 2250. According to Equation (19) and QQAM modulation, the theoretical maximum bit rate of the system can be calculated as \(R_{b}=\frac{1}{\Delta\tau\cdot M}\cdot n_{bit}=\frac{1}{2\times 100/3\times 10^{8 }\cdot 16}\cdot 200=18.75\) Mbps. \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Value** \\ \hline Pulse Repetition Time & 1.5 ms \\ Band Width & 15 MHz \\ Pulse Number & 16 \\ Pulse Width & 50 us \\ Carrier Frequency & 3 GHz \\ Target Velocity & 20 m/s \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Radar parameter configuration. \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Value** \\ \hline Overlapping Symbol & 4 \\ Simulation Length in Symbol & 100 \\ Bits per Subcarrier & 2 \\ Guard Bands on Both Sides & 212 \\ Signal Noise Rate & 12 dB \\ FFT Points & 1024 \\ Jamming Distance Gap & 100 m \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Joint system parameter configuration. We compared the proposed waveform with the communication rate in [12]. Our proposed method performed better than the latter's communication data rate of 0.2 Mbps. As discussed in Section 2, due to the complex target of the integration scenario, the received communication echoes have different time delays, and the integration platform will introduce multipath effects in the transmission process. When the OFDM waveform has spectral leakage, it will form serious interference with the remaining subcarriers during spreading due to the serious out-of-band interference of its subcarriers, thus affecting the waveform orthogonality. FBMC has good out-of-band rejection; while using OQAM coding, it can equalize the subcarriers individually and avoid inter-subcarrier interference by using the analysis filter at the receiver side to achieve multipath rejection. Figure 10 shows the communication performance of OFDM and FBMC waveforms in the presence of three paths. Figure 10a shows the BER at 150 m and 155 m with a three-path time delay, while the simulation results for the three-path delay of 2100 m and 2110 m are presented in Figure 10b. When the delay is exceeded, OFDM cannot suppress the multipath effect, and the BER cannot be reduced with increased SNR. The FBMC waveform is based on good out-of-band rejection, and inter-carrier interference is avoided by OQAM coding on subcarriers, which can effectively suppress the multipath phenomenon in combination with subcarrier equalization operation. Figure 11 shows the communication transmission simulation results of the joint signal. The diamond-shaped line is the relationship between the communication BER and SNR estimated from an ideal Rayleigh channel, while the hexagonal line shows the worsened BER results for the OFDM waveform due to non-orthogonal factors (e.g., Doppler shift). The blue line shows the result of the FBMC chirp waveform. As the SNR increases, the channel estimation performance improves, and the BER gradually approaches the ideal value. However, the red and black lines show that channel estimation errors occur when the multipath delay exceeds the duration of one symbol, which leads to a sharp deterioration in the BER. Figure 10: Comparison of communication performance under multipath delay (communication results with multipath delay less than CP (**a**) and communication results with multipath delay greater than CP (**b**)). We then compared the proposed algorithm with the state-of-the-art algorithm presented in [24] (see Figure 11). The latter results in an improved signal-to-noise ratio after coherent accumulation due to the inclusion of the slow time-dimensional fast Fourier transform in its radar signal processing. When the green line (see Figure 11) input SNR is greater than 6 dB, the bit error rate drops to less than \(10^{-4}\).