Sector beamforming with uniform circular array antennas using phase mode transformation

Phase-mode transformation is a frequently used method in beamforming with uniform circular arrays. By using this technique, the circular array is converted to a virtual uniform linear array. Consequently, beamforming techniques which need vandermonde structure of the steering vector, can be applied to the uniform circular array indirectly. It is necessary to use all sensors of the circular array in order to deploy the phase-mode transformation. In this paper, it is shown that when sensors of the array are directional, and also an optimum beamformer is deployed, it is sufficient to use only a sector of the array instead of all the sensors. Simulation results show that performance of the sector transformed beamformer is better than that of the ordinary transformed beamformer.

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