## 3 Analysis of Three-Stage Incremental Cooperative Communication
\begin{table}
\begin{tabular}{c l l l l} \hline \hline
**Technique** & **Feature** & **Domain** & **Flaws/Deficiencies** & **Results Achieved** \\ \hline MDTED [16] & Cooperative Spectrum Sensing & Cognitive WSNs, & Based on a single authorization user, number & Detection Accuracy, Improved \\  & Scheme, Location and & Cooperation-based & of nodes are fixed, and the value still needs to & collaborative sensing ability \\  & Channel-information dependent & networks & be computed & \\ \hline Cooperative routing [20] & Optimal power allocation according & WBANs & no consideration for end-to-end delay & Improved energy efficiency \\ \hline Probabilistic analysis [23] & Parametric model for health & WBANs & No realistic scenario, no consideration for & Improved network lifetime \\  & monitoring with & & end-to-end delay & \\  & probabilistic approach & & & \\ \hline RE-ATTEMPT [23] & Direct and multi-hop & WBANs & No retransmission of failed data packets, low & Energy Efficient and greater \\  & Communication & throughput & network lifetime \\ \hline ZigBee-Based [24] & Zigbee device for fall monitoring, utilizes anycast routing & WBANs & High energy consumption & Low transmission latency and \\  & & & & control overhead, reliable data \\ \hline Power-efficient & wake-up table for normal & WBANs & No QoS analysis, no multi-hop communication & Efficient in terms of power \\  & communication, on demand & & & consumption and delay \\  & external wake-up radio & & & \\  & for emergency & & & \\ \hline CLNC-MAC [29] & Cloud-based coordination by using & WBANs, cloud-assisted & Increased end-to-end delay, increased & collision avoidance, reliable data \\  & the RLNC technique & scheme & complexity & delivery with energy efficiency \\ \hline PEH-Q6 [30] & QoS-aware energy management, & WBANs, Human energy & Higher energy consumption in ECG detection & Improved throughput, detection \\  & only a useful data sequence is & harvesting WBAN & & efficiency, end-to-end delay \\  & transmitted & & & \\ \hline Opportunistic & Predefined relaying nodes for & WBANs & Delayed transmission and extra energy & Improved packet delivery rate \\  & data transmission & & consumption in relaying & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: _Cont._Now, we derive expressions for calculating PER for three-stage incremental relaying. Expressions for single- and two-stage relaying communication schemes may be seen in [6]. We also analyse the overall energy consumption for our proposed cooperative scheme. In WBANs, it is assumed that the link between two nodes is affected by path loss, shadowing and additive white Gaussian noise (AWGN). According to [2], the path loss model for WBANs, which is dependant on the distance \(d\) between communicating nodes, is based on the Friis formula in free space and is given as:  
\[PL(d)=PL(d_{o})+10 nlog\frac{d}{d_{o}} \tag{1}\]  
where \(PL(d_{o})\) is the path loss in dB at a reference distance \(d_{o}\) and \(n\) is the path loss exponent. Path loss due to distance may vary with body movement and certain changes in the surrounding environment. It may differ from its mean value, and this phenomena is called shadowing. Shadowing may also occur in a static body. By considering the factor of shadowing, the total path loss may be given as:  
\[PL=PL(d)+X_{\sigma} \tag{2}\]  
Here, \(X_{\sigma}\) is a shadowing factor in dB, which is a Gaussian-distributed random variable with zero mean and a standard deviation, \(\sigma\)[2]. According to the channel model for WBANs given in [2], the SNR at the receiver end is computed as:  
\[\gamma(dB)=P_{T}-PL-P_{N} \tag{3}\]  
where \(P_{T}\) is the transmit power and \(P_{N}\) is the noise power for all nodes.