## 3 System Implementation and Test
### Format of Communication Protocol and Data Analysis  
Detour path and traffic concentration problems are the fundamental problems of the general tree routing protocols [25], which cause overall network performance degradation. The forwarding scheme is prone to cause uneven load distribution and further lead to network congestion [26]. Nodes mounted on targets move frequently, and constant end-to-end paths are rarely available [27]. It is a challenging  
Figure 4: The PCB circuit of SNR (**a**) Battery and transceiver, (**b**) Microprocessor and sensor. Figure 3: Feature and installation of the SNR on a target (**a**) SNR, (**b**) Feature of the module, (**c**) Installation module on the target. task to maintain quality of service with respect to parameters such as high throughput, and minimum end-to-end delay [28; 29]. As shown in Figure 6, the receiver and each SNR use a program to measure the time to synchronize the data transmission cycle. However, if the data transmits and receives for a long time, data signal collisions and deviations occur at the same time in each transmitter. In order to solve this problem, each transmitter is synchronized by measuring time on each transmitter, and each transmitting time is revised by the receiver's origin time, which is the correct method. In Figure 7, each transmitter is performed by the program in its own time, but each transmitter's data packaged by the algorithm with original time is allocated a data packet. The final data packet can prevent data collisions and deviations on multiple transmitters operations. The data collects in the data base in the main system from each sensor which resulted from a packet of single transmitter or multi transmitter format. In some cases of the data transmission, the repeater makes a multi transmission format in a 600-s time limit and the raw data format can cover one target cattle every three seconds, so one packet can cover 200 target cattle every ten minutes [30]. Figure 5: Installation of the repeater with solar panel, (**a**) Installation, (**b**) Installation result, (**c**) Repeater. Figure 6: DATA Transmission in single repeater with single transmitter. The main system (receiver) has a packet communication protocol as shown in Tables 1 and 2. The data protocol has 15 units of packet. In this study, one kind of data is used, which is count number of physical activities of the targets. The packets could be extended, to such as temperature and humidity. The sensors of temperature and humidity need a lot of electric power for a long time operation. Thus, those sensors are not used in this study. The communication code is shown in the Table 1, the first column is the original time, and the second column is the received data packet. There are 15 units in every data packet shown as Figure 8.  
Table 2 interprets the unit formation by typical examples. The no. 0-2 units are for the Sync. from sensor, repeater and main system by wireless communication. The no. 3 is Sensor ID. The no. 4 is flag data for dividing from communication and activity data. The no. 5 is activity data which is accumulated from \begin{table}
\begin{tabular}{c c} \hline
**Repeater No. [01]** & **Receive Data** \\ \hline Origin Time & Received Data Packet \\ \hline
13:02:28 & FF FB FC F3 02 01 8C 9C 1B 39 00 07 FD FE FF \\
13:02:31 & FF FB FC 73 03 01 01 0B 2E 55 00 0A FD FE FF \\
13:02:34 & FF FB FC F3 04 01 00 06 4E FF 00 0C FD FE FF \\
13:02:36 & FF FB FC F3 05 01 71 33 5C 62 00 0F FF FF FF \\
13:02:39 & FF FB FC F3 06 01 55 68 1D D4 00 12 FD FE FF \\
13:02:42 & FF FB FC F3 07 01 16 35 D8 1E 00 15 FD FE FF \\
13:02:45 & FF FB FC F3 08 01 01 06 DE E1 00 18 FD FE FF \\
13:02:49 & FF FB FC F3 09 01 0D 14 D5 F3 00 1B FD FE FF \\
13:02:52 & FF FB FC F3 0A 01 03 27 0B F3 00 1E FD FE FF \\
13:02:55 & FF FB FC F3 0B 01 06 1B 19 39 00 21 FD FE FF \\ \hline \end{tabular}
\end{table} 
Table 1: The Sample of raw data received from packet. Figure 8: Structure of DATA unit of packet. Figure 7: DATA Transmission in single repeater with multi transmitter.