## 5 Solution of the Design and Testing
### Positioning and Construction  
**Real Case 2**. _Implementation and Measurement Practices of the Smart Town_. The empirical approach of this scholarly inquiry involved the utilization of ZigBee device CN-xxx, crafted by Freestyle Technology in Australia, which functioned as the node tasked with message reception. It was designated as the reference point for coordinate establishment, configuring an expansive outdoor positioning quadrant. In the realm of mobile anchor points, SM-ooo served as the ZigBee tag. Various data streams, encompassing signal strength and signal quality, transmitted by SM-ooo, were meticulously acquired through the CN-xxx. The analytical scrutiny of this pragmatic validation unfolded as follows. 1. System apparatus The distance considerations between blocks were as follows:  
1. Network planning system aspect: The best suggestion for positioning the arbitrage comparison device in conjunction with the natural gas company's geographical information system was 0 to 100 m.
2. The CN-xxx device, the best service area was based on 100 m: The empirical approach of this inquiry involved the utilization of the ZigBee device CN-xxx functioning as the node tasked with message reception. It was designated as the reference point for coordinate establishment, configuring an expansive outdoor positioning quadrant. 3. SM-ooo device specifications, the best service area was based on 100 m: In the realm of mobile anchor points, SM-ooo served as the ZigBee tag. Various data streams, encompassing signal strength and signal quality, transmitted by SM-ooo, were meticulously acquired through CN-xxx, as delineated in Tables 7 and 8. * The technical delineations of the CN-xxx device are presented in Table 8.
* Technical delineations of the SM-ooo device, as shown in Table 9.  
The functionalities of the device were ascertained utilizing ZigBee for network reference point localization. Upon receiving a message packet, the device autonomously appended an RSSI value to the informational packet. The system necessitated the provision of three to eight pixels before initiating the computation of the positioning coordinates. The coordinate value, the RSSI value of the reference point, and the A and n values of the reference must be inputted through the settings, as delineated in Equations (11) and (12). \[RSSI=-\big{(}10n\log_{10}d+A\big{)} \tag{11}\]  
where the variables are denoted as follows:  
n: constant representing signal propagation;  
d: representing the distance from the transmitter;  
A: signal strength received at one meter. The correlation between the measured distance and the known RSSI, A, and n values is articulated in Equation (12). \[d=10^{|((RSSI)-A|/10^{n})|} \tag{12}\]  
(3). RSSI and LQI measurements  
Based on two pivotal metrics in the localization, we scrutinized the data records of the signal strength information and LQI to unveil the data outcomes received at the recipient's end due to distance-related factors. Presented below are the authentic measurement outcomes of the ZigBee equipment. The association between the RSSI and the receiving distance is delineated in Table 9.  
An RSSI is a value that measures the strength of the signal received at the receiving end, as shown in Equation (13). \[SSI=10\times log\frac{P_{RX}}{P_{ref}} \tag{13}\] \begin{table}
\begin{tabular}{c c} \hline \hline
**Item** & **Specification** \\ \hline Frequency & 2.4 GHz \\ Modulation & O-QPSK \\ Maximum Transmission Rate & 250 kbps \\ Receive Sensitivity & \(-95\) dBm \\ Transmission Distance & 100 m (LOS) \\ Channel No. & 16 (5 MHz) \\ Tx Power & \(-24\) dBm to 0 dBm \\ Power Consumption Tx & \(<\)24 mA \\ Power Consumption Rx & \(<\)76 \(\mu\)A \\ \hline \hline \end{tabular}
\end{table} 
Table 8: SM-ooo specifications. \begin{table}
\begin{tabular}{c c} \hline \hline
**Distances (m)** & **RSSI (dB)** \\ \hline
0 & 210.69 \\
10 & 173.93 \\
20 & 172.49 \\
30 & 171.73 \\
40 & 171.15 \\
50 & 165.13 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Measurements of RSSI and distance intensity.