The increasing demand of data access and user experience result in deployment of new technologies (3G, LTE, WiMAX, Cognitive Radio), Long Term Evolution (LTE) is one of them which promises to fulfill the variable demand of subscribers through small cells instead of macro cells. The backhauling of the small cells in densely populated urban area is again a very difficult task to handle with Government regulations (eccentricities) and restrictions. Current trend in backhauling of small cells used fiber optic and twisted pair media result in increase in operational and deployment cost takes very long time and require permission from Govt. to deploy the cables, even Line of Sight (LoS) wireless link in densely urban area is not easy to achieve and non Line of Sight (NLoS) link result in decrease in power (signal strength) and require intelligent planning and difficult to operate and maintain. At the same time existing of new technologies in limited spectrum and to provide higher date rates for data traffic is again a challenge for mobile operators. The one possible solution to backhauling of small cells in NLoS situation is through cognitive radio spectrum sensing. In this thesis work the concept of spectrum optimization in small cells backhauling and challenges to achieve this have been introduced. Optimization has been done for different RF parameters and link budget of different networks in cognitive domain has been calculated and best possible network for backhauling of small cells is selected to enhance user demand.

Dedicated link between the transmitter and receiver is not always the case. To cater for, the later Non-Line-of-Sight communication is opted for especially in scenarios which include urban, dense urban or where re-planning is done on a constant basis to provide coverage to tricky areas. To address this concept of small cells was introduced but along with it backhauling emerged as a major problem. Wired and wireless solutions have been closely observed and out of which microwave backhauling stood out. With NLoS, propagation impairments get mounted and expected outcomes are hindered. An alternate to it as mentioned in our thesis is the approach of optimization of cognitive radio in NLoS backhauling of small cells. This approach has the potential of lowering the NLoS propagation impairments which include diffraction, reflection and scattering. At the same time it is an answer to cost, coverage and capacity.