This paper proposes a novel optical multibeam beamformer architecture capable of supporting multiple independent beams simultaneously. The architecture is based on a crossbar design, enabling efficient routing and combining of optical signals to form the desired beam patterns. A comprehensive theoretical analysis of the crossbar beamformer is presented, including performance metrics that demonstrate the efficiency and effectiveness of the crossbar architecture. Additionally, a comparison between the proposed beamformer and the traditional Blass matrix highlights an improvement of over 100 dB in insertion loss for a 1 dB phase shifter loss, as well as superior beamformer fidelity exceeding 99% for the crossbar architecture.