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Recently, stratospheric platform communications system (SPs) has gained great interest due to its superior performance compared to conventional communications systems. This paper addresses one of the major performance keys in SPs which is the cellular design based on adaptive concentric circular arrays (CCA). The proposed design technique aims to provide circular cells at any elevation angle to overcome the cell flattening and broadening which result in ellipsoidal cell shape. The cell footprint is controlled by adjusting the beamwidths which can be established by sectorizing the CCA and tapering the current amplitudes of the effective sectors by Hamming function while the others are muted and the resulted array is called Sectorized Hamming tapered CCA (SHTCCA). In this array, each sector has an angular width of 90o and some and two opposite sectors are fully fed while the others has less number of quarter-circular arrays. The tapering of the active sectors results in lower sidelobe levels which is a paramount improvement for the cellular systems. In addition, the SHTCCA is analyzed and optimized to provide the desired beamwidths at any elevation angle that are needed to design circular cell footprint

Sectorized Hamming Concentric Circular Arrays for Stratospheric Platforms Cellular Design