Introduction

Today's requirements for secure, interoperable communications systems, as well as rapidly deployable networks for emergency response, are driving the need for inexpensive, simple, satellite earth station antennas, ranging in size from sub-meter to 5 meters in diameter. When selecting and siting antennas, systems engineers rarely consider the earth station antenna's vulnerability to damage or destruction by the forces of nature or man.

The antenna, and in ...

Directional antennas in ad hoc networks offer many benefits compared with classical omnidirectional antennas. The most important include significant increase of spatial reuse, coverage range and subsequently network capacity as a whole. On the other hand, the use of directional antennas requires new approach in the design of a MAC protocol to fully exploit these benefits. Unfortunately, directional transmissions increase the hidden terminal problem, the problem of deafness and the problem of ...

This paper presents a real-time utility based procedure for antenna tilt control in cellular networks. The method’s convergence to Nash equilibrium is guaranteed by the concave dependence between utility function and tilt angle. The solution was verified using a CDMA motion simulator with real path-loss data collected in downtown Delhi. The simulations show a significant reduction in dropped calls when the tilt is adapted to changes in traffic. This solution can be realized on systems that ...