Adaptive Pulse Design and Spectrum Handoff Technology Based on Cognition

Cognitive ultra wideband wireless communication system is a new type of intelligent communication system, which provides an effective method to relieve the shortage of the spectrum resource. In order to avoid interference with existing communication systems, this new one has a high demand for pulse design and spectrum handoff. This paper presents a flexible multi-band adaptive pulse design method and a proactive spectrum handoff mechanism which applies to the pulse above, the aim of that is expect to reduce the spectrum loss during the spectrum handoff and improve spectrum utilization. Experimental results show that on the condition of one cognitive user channel only hold a licensed user, the pulse spectrum utilization can reach above 80%, the system spectrum utilization is not affected by the arrival rate of licensed users.