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Numerical analysis of level of uncoupling between transmitting and receiving broadband arrays with allowance for beam formers



Published: 03/25/2008
Original: missing
© 1996, V. V. Koryshev, V. I. Chulkov
© 2008, EDS–Soft,  http://www.eldys.org,   E-mail: publications@eldys.org


In case of different destination antenna saturation modern radio systems the array antenna (AA) bypassing, located in bounded capacity, in angle region near ±600 of principal plane and frequency band with contact ratio no less than 2, increase means much. At that essential bypassing magnitude between receiving AA outcome and transmitting AA input can reach -100…-130 dB.

In case of AA coupling value analyzing, usually the following construction is taken [1] (fig.1): L active transmitters of two–dimensional array are connected to first outcome of emitting subarray beam former (BF1), М emitters are connected to certain secondary radiator (for example, it`s loaded to matched resistance) of decoupling subarray, N secondary radiators are connected to second emitting subarray beam former (BF2). The S2 and S22 scattering matrix choice, then BF1 and BF2 characteristic of active and secondary subarrays [1…3] fixed, is worthy of notice. BF1 and BF2 characteristic influence and mutual coupling magnitude between emitters of emitting and secondary subarrays are of less importance.

Figure 1. Antenna system scheme.

In the article bypassing magnitude calculation results for special cases of gain–phase distribution (GPD) in BF1 and BF2 outcomes are given. It can be gotten if wideband microstrip antenna array (WMAA) [4] would be used as single transmitter–receiver curtain. Suppose that both BF have isolated and matched outputs and decoupling subarray is absent (M = 0). Then coupling coefficient expression looks like this [1]:

(1)

where Y12 — dimension matrix 1xN of complex transfer constant coefficients from BF2 outcomes to it`s input; X21 — dimension matrix Lx1 of complex transfer constant coefficients from BF1 input to it`s outcomes; C31 — Toeplitz matrix of coupling coefficients between emitters of emitting and secondary subarrays.


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References

1. Agafurov I. N., Lavrushev V. I., Sedelnikov Y. E. Passive radiator usage in points of antenna decoupling increase. – Kazan: KAI, 1985 – Dep. UISTI, №3495–85. (In Russian).
2. Lavrushev V. I., Sedelnikov V. I. Antenna construction taking into account decoupling request //Radioelectronica, – 1980, v.XXIII, №2, р.31…38. (In Russian).
3. Kyurkchan A. G. The bond between antennas with ribbed structure present// Radiotechnics and Electronics. – 1977, v.XXII, №7, p.1362…1373. (In Russian).
4. Chulkov V. I. About widebandedness of flat antenna arrays of microstrip radiators. // Second All−Union Science−Technical conference “Devices and methods of applied electrodynamics”, 9…13 September, 1991 (Odessa). Report theses. – M.: MAI, 1991, p. 148. (In Russian).
5. Chaplin A. F. Analysis and synthesis of antenna arrays. – Lvov: LSU, 1987. – 179p. (In Russian).
6. Barton D., Vard G. Handbook on radar measuremnts/Translated from English edited by Veisbein M. M. – M: Sov. radio, 1976. – 392p. (In Russian).
7. Korn G., Korn T. Reference book for persons engaged in scientific research and engineers. //Translation from English edited by Aramanovich I. G. – М.: Science, 1968. – 720p. (In Russian).
8. Handbook on special functions/Edited by. M. Abramowitz and I. Stigan /Translated from English by V. A. Ditkin and L. N. Karmazina. – M.: Nauka, 1979. – 830 p. (In Russian).