Frequency invariant beamforming using sensor delay line

Abstract

Wideband operation and pattern shaping in one dimension can be achieved using a planar array antenna with a real-valued coefficients or weights. The extra dimension is used to sample the signal in space and treat each frequency independently. Two methods to calculate the weights for the desired array pattern have been compared. These are Spatial Response Variation Constraint Pattern Synthesis (SRVCPS) and Inverse Discrete Fourier Transform (IDFT). The SRVCPS method relies on optimizations. The Spatial Response Variation (SRV) is constrained to ensure wideband operation. The IDFT method applies inverse Fourier transformation to the desired pattern which produces the required weights. Methods are compared in terms of beamwidth, sidelobe level and processing speed.