## 3 Implementation and Validation  
### Implementation of Enhanced Data Transmission Mode and Validation  
Compared to the IEEE 802.11p standard, the IEEE 802.11 bd standard demonstrates remarkable advancements in communication performance, particularly in the data transfer rate, where the modulation and coding scheme (MCS) and coding rate (R) are pivotal factors. While the MCS and R combinations used in 802.11p have been integrated into Veins, this research introduces three new modes from 802.11 bd, i.e., 64-QAM 5/6, 256-QAM 3/4, and 256-QAM 5/6. To implement these three new MCS and R combinations in Veins, it is essential to comprehend their functioning in fusion simulations. As data packets are transmitted, the MCS and R combination directly influences the data transfer rate, which, in turn, determines the number of data bits per OFDM symbol (\(N_{DBPS}\)). See Table 2 for specific correspondences. In the simulation implementation of Veins, the \(N_{DBPS}\) and the length of the data packet (\(L_{Data}\)) will largely determine the sending time of the data packet (\(T_{FrameDuration}\)), as shown in Equation (1). Since the preamble of the PPDU uses the data transmission mode (BPSK 1/2) with the lowest data transfer rate (6.8 Mbps) and the format/length of the preamble field is fixed, the sending time of the preamble field (\(T_{Preamble}\) and \(T_{Signal}\)) is fixed. By adjusting the parameters, e.g., \(T_{Preamble}\), \(T_{Signal}\), and \(N_{DBPS}\), we can replicate the NGV PPDU frame format and data transfer rate of the IEEE 802.11 bd standard. Figure 2: Example of NON_NGV_10 repetition transmission. \[T_{FrameDuration}=T_{Preamble}+T_{Signal}+T_{Symbol}\times\left|\frac{16+L_{Data}}{N _{DBPS}}\right| \tag{1}\]  
The enhanced data transmission mode not only involves increasing the data transfer rate of the sending STA but also raises greater challenges in receiving STAs by requiring an increased transmission SNR. In the data packet reception simulation conducted in Veins, the data transmission mode (MCS and R) determines the theoretical Bit Error Rate (BER) calculation. Initially, the basic BER is determined based on the SNR and MCS, and then it is adjusted according to R to derive the theoretical BER. Subsequently, the probability of the entire data packet being successfully received is computed based on the data packet length. This probability is then cross-verified with a random number to ascertain successful decoding and reception. Thus, implementing the three newly introduced enhanced data transmission modes of 802.11 bd involves the incorporation of the newly introduced MCS 256-QAM and the newly introduced R 5/6. The calculation formula for MCS in Veins is based on the Additive White Gaussian Noise (AWGN) channel, an idealized model widely used in communication evaluation. This model aptly approximates the statistical attributes of noise and interference in the real world. We can derive Equation (2) for the theoretical BER of 256-QAM based on the BER calculation formula for Quadrature Amplitude Modulation (QAM) in the AWGN channel. This formula and its related code can then be implemented in Veins. \[BER_{256-QAM}=\frac{15}{64}erfc\bigg{(}\sqrt{\frac{SNR}{170}}\bigg{)} \tag{2}\]  
The polynomial parameters used to calculate the theoretical BER correction based on the coding rate in Veins are obtained from [32] on high-rate punctured convolutional codes. These parameters specifically come from the free distance of the punctured code and the coefficients of the series expansions of the corresponding weight spectra of short-memory punctured codes with different coding rates. To obtain the desired parameters for the 5/6 coding rate, we refer to the generators of the original code and the perforation matrix of the 2/3 and 3/4 coding rates and convert them into Equation (3). \[ \begin{split} P_{E_{\frac{5}{6}}^{5}}=\frac{1}{10}\Big{(}92D^{4}+ 528D^{5}+8694D^{6}+79453D^{7}+792114D^{8}+7375573D^{9}+\\ 67884974D^{10}+610875423D^{11}+5427275376D^{12}+47664215639D^{13} \Big{)}\end{split}