Congestion in mobile radio network has been a great challenge due to increase in demand by the mobile users on the limited available channels. Dynamic channel assignment technique was employed in this work to minimize congestion in the network. Twelve base stations were studied and analyzed using some telecommunication traffic Key performance indicators (KPI) such as Call Completion Rate (CCR), Grade Of Service (GOS) and Channel Utilization Percentage (CUP). The result of the analysis was compared with the Nigeria Communication Commission (NCC) regulatory standards. It was discovered that call completion rate (CCR) of all the Base Transceiving Stations (BTSs) investigated were not in accordance with NCC standard. Math lab program for Erlang B model used to evaluate the call congestion and call blocking probability on the network was developed and used in observing the system. The result of analysis of the system based on simulation of Erlang B model showed that the call congestion probability in some BTS were approximately equal to zero while the others were highly congested with higher probability of calls being blocked when fixed channel assignment technique was implemented. The model for the chosen technique for this work (Dynamic Channel Assignment Technique ) was used to simulate the 12 base stations investigated. The result showed lower probability of call congestion when compared with those BTSs with higher probability of call congestion. Thus congestion was minimized and more calls accommodated when compared with fixed channel assignment technique. Algorithm for implementing the technique was developed and modeled using flow graph.

This paper is on improving medium wave signal transmission using a flexible impedance matching unit. The system is T arrangement of impedance network that provides impedance matching between the transmitter and antenna. The parallel feeder used in the medium frequency ground wave signal transmission gives rise to a mismatch between antenna and the generator (transmitter). This network is a lumped reactance that effectively matches the transmitter to the antenna. The vertical antenna used in this range of frequency require a radial wire earth to achieve good ground; with effective connection to the matching network a good path to ground was achieved and noise associated with the transmission line was highly reduced.