PRT Communication
The backbone of the communication network is a glass fiber cable connected to the supervisory control system SuperFROG. All infrastructure elements (e.g. the passenger interfaces and cameras at stations, the crossing controls) and the access-points for wireless LAN communications with the vehicles are connected to this backbone.
The vehicles communicate with the supervisor for information exchange on vehicle control and monitoring (status, traffic control, job assignments and energy management), images of the on-board cameras and the intercom (Voice over IP). The number of access points for wireless communication and type of antennas must be determined by a site survey, because this will be influenced by the environment (e.g. buildings, trees and other ‘radio’ or radar signals).
The preferred wireless-LAN communication system is based on the 802.11a standard that delivers a raw bit rate of 54 Mbps. This system operates in the 5.4 to 5.7 Ghz band and can use 11 independent frequency channels. In case a channel is disturbed or used by other systems, a different channel can be selected. The system is ´hacker-proof´ through passwords, data encryption and IP-address verification. As alternative the 802.11g standard, operating in 2.4 Ghz band can be used.
The access points of the communication system should be protected from vandalism. As standard they are mounted on top of a >4 meter high post, which is equipped with a climbing protection ring. The stationary cameras along the track can also be installed on the post(s). For maintenance purposes the post preferably is tiltable.
Specification wireless-LAN:
| Basic Standard / Frequency: | 802.11A / 5.4 – 5.7 Ghz | |||||
| Alternative Standard / Frequency: | 802.11G/ 2.4 Ghz | |||||
| Distance between access points: | 250 meter |