Wireless communication explores new era of ease of information exchange through human-machine and machine-machine interaction to deal various real time applications. This has created a great spectrum scarcity to deal high bandwidth smart applications. The cognitive radio is an advance approach to manage spectrum congestion through dynamic spectrum access (DSA). The unlicensed secondary users are being allowed to access unutilized spectrum of primary licensed users through opportunistic scan. This elicits the need of an UWB antenna for wireless sensor networks to explore every possible vacant channel opportunity during scan. A novel UWB antenna is proposed here for wireless cognitive radio sensor network (WCRSN) to scan maximum RF spectrum as per FCC standard. Antenna offers matched impedance bandwidth for wide spectrum range from 3.3-11.5 GHz with sustainable 4.0 dBi high gain and bidirectional radiating properties for the entire frequency sweep.