Design and performance analysis of a wireless multi-hop network for data transmission in elevator systems

Many researches have been conducted to utilize wireless technology in order to control the floor fixtures of elevators. Elevator companies are trying to discover new ways to avoid the problems related to the traditional approaches. The main goals essentially are decreasing the number of cables used, the elevator installation period, the time of troubleshooting and increasing the service quality provided to users. In this thesis, the most common wired and wireless data transmission techniques between the control panel and the floor fixtures have been evaluated, and their positive and negative effects have been determined. In the light of this evaluation, the feasibility of using energy harvesting technology and Wireless Short Packet (WSP) protocol to control the floor fixtures has been analyzed and, as a result, two networks have been designed. The first one is a multi-hop wireless network for low-rise and medium-rise buildings. The second one is a hybrid wired-wireless network designed for high-rise buildings. For the performance test of the two networks, the required equipment has been purchased and 3 experimental setups have been built. While testing the TCM320 module, which uses the WSP protocol, the maximum telegram intensity the module can operate in without errors has been found to be 75 telegram/s. This corresponds to a 13.33 ms telegram window. The signal of the module has been proven to penetrate up to 6 floors in the building where the test has been conducted. In the first network, when using telegrams with 13-byte length, in the best case, hop time (t_a) has been determined as 16.1 ms, while in the worst case it has been found as 56.1 ms. The maximum number of floors (N) that can be served in both cases has been determined according to the call button response time (c_t). For c_t values of 50, 100, 200, 300, 400, 500, 1000 ms, in the best case, N has been computed as 6, 12, 24, 37, 49, 62, 124, and in the worst case, N has been found as 1, 3, 7, 10, 14, 17, 35, respectively. In the second network, CANbus has been used with TCM320 modules. In this network, short and constant data transmission period allows the network to be implemented in high-rise buildings. N value has been computed as 325 when CANbus is in normal mode, and it has been computed as 295 when the TJA1055T controller is in CANbus fault-tolerance mode.