Edge-Born Waves in Connected Arrays: A Finite$\,\times\,$Infinite Analytical Representation

Connected arrays constitute one of the most promising options for wideband phased arrays. Like most phased arrays, they are designed using infinite array theory. However, when finiteness is included, edge effects perturb their behavior. These effects are more severe when the arrays are designed to operate over very broad frequency ranges, since the mutual coupling between the elements facilitates the propagation of edge-born waves that can become dominant over large portions of the arrays. Finite array simulations, which would predict these behaviors, are computationally unwieldy. In this paper we present a Green's function based procedure to assess edge effects in finite connected arrays. First the electric current distribution on the array is rigorously derived. Later on, the introduction of a few simplifying assumptions allows the derivation of an analytical approximation for the current distribution. This latter provides meaningful insights in the induced dominant edge-wave mechanism. The efficiency of connected arrays as a function of their dimension in terms of the wavelength and of the loading feed impedances is investigated.

[1]  High-frequency analysis of an array of line sources on a truncated ground plane , 1998 .

[2]  M. Albani,et al.  Truncation effects in a semi‐infinite periodic array of thin strips: A discrete Wiener‐Hopf formulation , 2009 .

[3]  Andrea Neto,et al.  Green's Function Based Equivalent Circuits for Connected Arrays in Transmission and in Reception , 2011, IEEE Transactions on Antennas and Propagation.

[4]  R. Hansen Phased Array Antennas , 2009 .

[5]  B. L. Waerden On the method of saddle points , 1952 .

[6]  P. Pathak,et al.  On the Poisson sum formula for the analysis of wave radiation and scattering from large finite arrays , 1999 .

[7]  Efficient hybrid discrete Fourier transform-moment method for fast analysis of large rectangular arrays , 2002 .

[8]  D. S. Janning,et al.  Effects of surface waves on the currents of truncated periodic arrays , 2002 .

[9]  Stefano Maci,et al.  Frequency-domain Green's function for a planar periodic semi-infinite phased array .I. Truncated floquet wave formulation , 2000 .

[10]  J. Mosig,et al.  Finite phased array of microstrip patch antennas: the infinite array approach , 1992 .

[11]  D. Cavallo,et al.  Scanning performance of wide band connected arrays of dipoles , 2009, 2009 3rd European Conference on Antennas and Propagation.

[12]  R. C. Hansen,et al.  Linear Connected Arrays , 2004 .

[13]  Lawrence Carin,et al.  Time harmonic and transient scattering by finite periodic flat strip arrays: hybrid (ray)-(Floquet mode)-(MOM) algorithm , 1993 .

[14]  R. C. Hansen Finite array scan impedance Gibbsian models , 1996 .

[15]  R. C. Hansen,et al.  A Gibbsian model for finite scanned arrays , 1996 .

[16]  O.A. Civi,et al.  Array guided surface waves on a finite planar array of dipoles with or without a grounded substrate , 2006, IEEE Transactions on Antennas and Propagation.

[17]  John L. Volakis,et al.  Antenna Engineering Handbook , 2007 .

[18]  Giuseppe Vecchi,et al.  A truncated Floquet wave diffraction method for the full wave analysis of large phased arrays. I. Basic principles and 2-D cases , 2000 .

[19]  Raj Mittra,et al.  Numerical and experimental studies of a dual-polarized planar connected-array antenna for the Australian Square Kilometer Array Pathfinder , 2009, 2009 IEEE Antennas and Propagation Society International Symposium.

[20]  X. Dardenne,et al.  Element pattern analysis of wide-band arrays with the help of a finite-by-infinite array approach , 2006, IEEE Transactions on Antennas and Propagation.

[21]  R. Kouyoumjian,et al.  A uniform geometrical theory of diffraction for an edge in a perfectly conducting surface , 1974 .

[22]  S. Livingston,et al.  A low profile 10:1 (200–2000 MHz) wide band long slot array , 2008, 2008 IEEE Antennas and Propagation Society International Symposium.

[23]  Hansen Linear connected arrays [coupled dipole arrays] , 2004, IEEE Antennas and Wireless Propagation Letters.

[24]  N. Amitay,et al.  Theory and analysis of phased array antennas , 1972 .

[25]  Stefano Maci,et al.  Frequency Domain Green’s Function for a Planar Periodic Semi-infinite Phased Array. Part II: Phenomenology of the Diffracted waves , 2000 .

[26]  A. Neto,et al.  Ultrawide-band properties of long slot arrays , 2006, IEEE Transactions on Antennas and Propagation.