## 3 Related Work  
Despite being introduced in the IEEE 802.15.4g-2012 amendment, the SUN-OFDM PHY has not received a lot of attention from the research community to understand the potential benefits (and pitfalls) of applying this technology in low-power wireless communications for industrial applications. This is mainly due to the lack of commercially available radio transceivers that support all standard modes. In this section, we provide a summary of related work that has evaluated the \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Type**} & \multirow{2}{*}{**Mode**} & \multirow{2}{*}{**Modulation**} & \multirow{2}{*}{**Coding Rate**} & \multirow{2}{*}{**Frequency Repetition**} & \multirow{2}{*}{**Channel/Nominal Bandwidth (kHz)**} & \multirow{2}{*}{**Total/Data/Pilot Tones**} & \multirow{2}{*}{**Effective Datarate (kbps)**} \\ \cline{5-8}  & & & & & & & 100 \\ \hline \multirow{4}{*}{**OFDM1**} & MCS0 & BPSK & 1/2 & 4x & & & 100 \\ \cline{2-8}  & MCS1 & BPSK & 1/2 & 2x & & & 200 \\ \cline{2-8}  & MCS2 & OQPSK & 1/2 & 2x & & & 400 \\ \cline{2-8}  & MCS3 & OQPSK & 1/2 & 0x & & & 800 \\ \hline \multirow{4}{*}{**OFDM2**} & MCS0 & BPSK & 1/2 & 4x & & & 50 \\ \cline{2-8}  & MCS1 & BPSK & 1/2 & 2x & & & 100 \\ \cline{2-8}  & MCS2 & OQPSK & 1/2 & 2x & & & 200 \\ \cline{2-8}  & MCS3 & OQPSK & 1/2 & 0x & & & 400 \\ \cline{2-8}  & MCS4 & OQPSK & 3/4 & 0x & & & 600 \\ \cline{2-8}  & MCS5 & 16-QAM & 1/2 & 0x & & & 800 \\ \hline \multirow{4}{*}{**OFDM3**} & MCS1 & BPSK & 1/2 & 2x & & & 50 \\ \cline{2-8}  & MCS2 & OQPSK & 1/2 & 2x & & & 100 \\ \cline{2-8}  & MCS3 & OQPSK & 1/2 & 0x & & & 200 \\ \cline{2-8}  & MCS4 & OQPSK & 3/4 & 0x & & & 300 \\ \cline{2-8}  & MCS5 & 16-QAM & 1/2 & 0x & & & 400 \\ \cline{2-8}  & MCS6 & 16-QAM & 3/4 & 0x & & & 600 \\ \hline \multirow{4}{*}{**OFDM4**} & MCS2 & OQPSK & 1/2 & 2x & & & 50 \\ \cline{2-8}  & MCS3 & OQPSK & 1/2 & 0x & & & 100 \\ \cline{2-8}  & MCS4 & OQPSK & 3/4 & 0x & & & 100 \\ \cline{2-8}  & MCS5 & 16-QAM & 1/2 & 0x & & & 200 \\ \cline{2-8}  & MCS6 & 16-QAM & 3/4 & 0x & & & 300 \\ \hline \hline \end{tabular}
\begin{tabular}{c c c c} \hline \hline \multicolumn{2}{c|}{**SHR**} & \multicolumn{2}{c}{**PHR**} & \multicolumn{2}{c}{**PHY Payload**} \\ \hline STF & LTF & PHY Header & PSDU & PPDU Tail & Pad \\ (Variable) & (Variable) & (Variable, \(\leq\)2047 bytes) & (6 bits) & (Variable) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: SUN-OFDM parameters. Figure 2: IEEE 802.15.4-2015 SUN-OFDM frame format. performance of the PHYs proposed in the IEEE 802.15.4g-2012 amendment. The results are presented in chronological order. In [10], the authors experimentally evaluate various LPWAN (Low-Power Wide-Area Network) technologies for industrial sensing applications, including condition monitoring. The results, which include LoRa (Long Range) and IEEE 802.15.4g (using SUN-FSK only), conclude that, with respect to IEEE 802.15.4g (SUN-FSK), LoRa provides the largest communication range (2\(\times\)) at the expense of an increased energy consumption (10\(\times\)). In [11], the authors study the coexistence mechanisms of homogeneous and heterogeneous IEEE 802.15.4g systems for SUN, and perform a coexistence analysis to evaluate the performance degradation of a victim system in the presence of an interferer. They show that, with a distance over 30 m, the victim and the interferer are able to coexist even without any higher layer mechanism that enforce coexistence. In [12], the authors study the coexistence of IEEE 802.11 ah and IEEE 802.15.4 g networks, which provide communication ranges above 1 km, and are specifically targeted at outdoor IoT (Internet of Things) applications. Simulation results show that co-located IEEE 802.11 ah networks can severely impact the operation of IEEE 802.15.4 g networks due to the higher ED (Energy Detection) threshold and the faster back-off mechanism. Moreover, the differences in modulation scheme and frame structure limit the capability to implement automatic mechanisms to enforce cooperation.