## 1 Introduction
The proposed environment is considered at the hospital, and it has obtained a limited number of licensed bands (due to higher in cost) for accessing the patient's BNC from collecting the physiological data from the IMD to the hospital server. The number of users of the In Patient-Body Network Controller (IP-BNC) is pre-determined, and a fixed number of licensed channels is assigned to the IP-BNC. The rest of the licensed channels are assigned to the OP-BNC. During the peak visiting hours of the hospital, when the number of OP-BNC users increases, the scarcity for the licensed PU channels increases, as the server has to fetch the data from the OP-BNC for a secure communication. This situation is managed by using the unlicensed SU channel. These unlicensed bands are used by \begin{table}
\begin{tabular}{c l l l l l} \hline \hline \multicolumn{1}{c}{**WBAN**} & \multicolumn{1}{c}{**Signals**} & \multicolumn{1}{c}{**Data Range**} & \multicolumn{1}{c}{**Frequency**} & \multicolumn{1}{c}{**Accuracy**} & \multicolumn{1}{c}{**Data Rate**} \\ \multicolumn{1}{c}{**Applications**} & \multicolumn{1}{c}{} & \multicolumn{1}{c}{} & \multicolumn{1}{c}{} & \multicolumn{1}{c}{} & \multicolumn{1}{c}{} & \\ \hline \multirow{6}{*}{Medical/Health} & Glucose Concentration & 0–20 mM & 40 & 12 & 480 bps \\  & Blood Flow & 1–300 mL/s & 40 & 12 & 480 bps \\  & ECG & 0.5–4 mV & 500 & 12 & 6 Kbps \\  & Respiratory Rate & 2–50 breaths/min & 20 & 12 & 520 bps \\  & Pulse Rate & 0–150 BPM & 4 & 12 & 48 bps \\  & Blood Pressure & 10–400 mm Hg & 100 & 12 & 1.2 Kbps \\  & Blood pH & 6.8–7.8 pH & 4 & 12 & 48 bps \\  & Body Temperature & 32–40 \({}^{\circ}\)C & 0.2 & 12 & 2.4 bps \\ \hline \hline \end{tabular}
\end{table} 
Table 1: WBAN Application Operating Range [8]. Figure 2: Data Rate vs. Power. the OP-BNC MDs, which are unsafe to communicate the Physiological Signal (PS) of the patients with IMDs. The problem that arises over here is that all the OP-BNCs must be assigned a licensed frequency in order to protect the data and device from attackers without the need for extra bandwidth. This problem is solved by lending the licensed spectrum of PUs (when idle) to the IP-BNC with an optimized algorithm without affecting the communication of the IP IMDs. The existing node selection algorithms are used in the selection of unused PU channels dedicated for the IP-BNC channel. In this algorithm, the idle PUs are listed and a Look-Up Table (LUT) is created, and these idle PU channels are assigned to the OP-IMD to protect the medical information [9]. In this methodology, two problems are identified: Firstly, the rank-based channel selection algorithm is applied; here, the ranking is done based on the value of Bit Error Rate (BER). When the BER value is constantly low, due to repeated use of the same channel, a busy situation is created always. When the intended PU comes back for the channel, this busy mode creates a collusion, resulting in a loss of data. Secondly, the ranking-based dynamic channel selection algorithm increases the execution time by calculating the BER for each channel that is idle and adds to the LUT, allowing it for the ranking process there and affecting the overall system performance. These two problems motivated us to develop a novel optimization-based dynamic channel selection algorithm called the EFPOC algorithm, which is an ideal dynamic spectrum selection algorithm. Assigning the idle PU spectrum in the existing LUT with BER calculation in the dynamic channel selection is very time consuming. The EFPOC dynamic channel selection algorithm is an optimized algorithm, creating its importance by reducing the channel selection time supported with the algorithm complexity. With the EFPOC algorithm, the process overhead and time is reduced. As the BER calculation is processed only after the channel allocation, the BER calculating time for all the idle channels during the entry at the LUT is completely eliminated by the EFPOC algorithm. The paper is divided into six sections. Section 2 consists of a literature survey of cognitive radio with WBAN.