Felicia Ong

This paper presents an underground subsurface wireless sensor for drainage infrastructure water level monitoring. It operates from 800 to 2170 MHz to cover the required GSM850/900, GSM1800/1900 and UMTS bands. The system consists of a wideband antenna, transceiver, data acquisition unit and an ultrasonic sensor. The proposed antenna is a 3-dimensional inverted double F antenna and has an envelope size of 90 × 63.5 × 32 mm^3 , which is acceptably small for a cramped subsurface passageway environment. The antenna design was developed using software simulation to optimise its key parameters of return loss and radiation pattern, these being evaluated both in free space and in the partially underground environment. The design developed was then realised in hardware and tested in a representative subsurface location: a utility manhole chamber. It was found that the location of the antenna in the chamber had a significant effect on its performance, but a location that was acceptable for operational purposes was found by experiment. The overall system, including a transceiver, was demonstrated to operate satisfactorily for utility monitoring purposes, including acceptable levels of path loss for communication with mobile communication base stations.

The recent surge in the development of new technologies, most especially in the field of mobile and wireless communications, requires the adequate maintenance and overall procurement of network infrastructures. this is due to a great deal of accelerating demand from Mobile users having access to real-time information such as data, voice and video services. Therefore, the operators and service providers require seamless integration of network protocols with an improved quality of service (QoS). This paper addresses the performance of multimedia services in Multiprotocol Label Switching (MPLS) nodes and network models design using simulation approach. MPLS ensures the reliability of the communication minimizing the delays and enhancing the speed of packet transfer. It is valuable in its capability of providing Traffic Engineering (TE) for minimizing the congestion by efficient throughput. The verification of the MPLS model will be the focus of the performance evaluation. An elaborate description of MPLS and its principle of operation will be required. It will eventually address the challenges of packet loss, high latency, high operational cost, more bandwidth utilization, and poor QoS.