Reconstructing a nonminimum phase response from the far-field power pattern of an electromagnetic system

• Published in: IEEE transactions on antennas and propagation Vol. 53; no. 2; pp. 833 - 841
• Main Authors: Jie Yang, Jinhwan Koh, Sarkar, T.K.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.02.2005; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Antenna arrays; Antennas; Applied sciences; Autocorrelation; Cepstrum; Current distribution; Delay effects; Delay lines; Discrete Fourier transforms; Electromagnetic fields; Exact sciences and technology; Filters; Fourier transforms; Magnitude-only data; nonminimum phase; phase reconstruction; Radiocommunications; Telecommunications; Telecommunications and information theory; Transfer functions; Linear phase; Discrete Fourier transformation; Far field; Computational complexity; Electromagnetic device; nonminimum phase; Magnitude-only data; All pass filter; Phase function; Spatial distribution; Current distribution; Phase delay; Autocorrelation; Causality; Antenna array; Phase reconstruction; Antenna radiation patterns
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2004.841335

A new technique for reconstructing the nonminimum phase function from magnitude-only data is presented in this paper. The nonminimum phase function is reconstructed by utilizing the fact that the discrete Fourier transform of the far field power pattern is equal to the autocorrelation of the equivalent spatial current distribution on the electromagnetic structure. An all-pass filter representation is also used to reduce the computational load in computing the nonminimum phase function. The solution for the phase is not unique but is up to a linear phase delay between the actual phase function and the phase produced by the current approach. However, we generate a solution which has a spatially causal response, as the antennas are all finite in size. This approach is applied to the synthesis of nonminimum phase functions from the magnitude only antenna pattern. Several examples dealing with single antennas and antenna arrays have been simulated to illustrate the applicability of this approach.