Frequency Diverse Array with Quadratic Variation In Frequency Offset

Document Type : Original Article

Authors

Abstract

It has been shown over several decades of radar research that the exploitation of diversity in a number of domains such as space, frequency, time, polarization, and, recently, waveform can provide increased agility, flexibility, reliability, and capabilities to the radar system. However this is often achieved either through efforts in system design, increased hardware complexity, or by employing additional resources. In the frequency diverse array (FDA) the subsequent antenna elements are fed with stepped discrete frequencies. So a range-angle dependent radiation pattern is made possible .
It is possible to apply different frequencies with different patterns to the elements of FDA to achieve different radiation pattern.
In this paper, a frequency diverse array with non-uniform inter-element frequency offset called quadratic-FDA has been proposed, that its variation is a function of physical distance of elements from the first element.
To produce the coefficient of the frequency offset two Frequency offset generators has been proposed. In The first proposed method uses linear distance as a input of function and the second one uses multiples of the roots of the Chebyshev polynomial.
The proposed strategy provides a non-periodic beampattern, with a maximum that can be steered in space by selecting appropriate excitation weights of the antennas. This single-maximum beampattern, in contrast to multiple-maxima beampattern of the other forms of FDA, can help to further reject range-dependent interferences, causing improved SINR and increased detectability

Keywords


 
[1]Barton, D. K. "Frequency Agility and Diversity" Norwood, MA: Artech House, 1977.
[2] H. E. Shanks, “A new technique for electronic scanning,” IRE Trans. on Antennas and Propagation, vol.  9, pp.162 -166, March 1961.
[3] P. Antonik, M. Wicks, H. Griffiths, and C. Baker, “Frequency diverse array radars,” in Radar, 2006 IEEE Conference on, p. 3 pp., 2006.
 [4] P. Antonik, M. Wicks, H. Griffiths, and C. Baker, “Multi-mission multi-mode waveform diversity,” in Radar, 2006 IEEE Conference on, p. 3, IEEE, 2006.
[5] Farooq, J., Temple, M. A., and Saville, M. A.Application of frequency diverse arrays to syntheticaperture radar imaging.In Proceedings of the International Conference onElectromagnetics in Advanced Applications (ICEAA 2007),Torino, Italy, Sept. 2007, pp. 447—449.
[6] Farooq, J., Temple, M. A., and Saville, M. A.Exploiting frequency diverse array processing to improveSAR image resolution.In Proceedings of the IEEE Radar Conference, (RADAR’08), Rome, Italy, May 2008, pp. 1—5.
[7] Baizert, P., et al.Forward-looking radar GMTI benefits using a linearfrequency diverse array.Electronics Letters, 42, 22 (2006), 1311—1312.
[8] Waseem Khan, IjazMansoorQureshi, Sarah Saeed, “Frequency Diverse Array radar with Logarithmically Increasing Frequency Offset”IEEE Antennas and Wireless Propagation Letters,2013
[9]عسکری،.مرضیه ، محسنی ارمکی ،سید حسین و فلاح ، مخسن. "تحلیل الگوی تشعشعی آرایه آنتن با چندگانگی فرکانس مبتنی بر مدولاسیون مجذور فرکانس موج پیوسته " مجله رادار، سال سوم، شماره 1، بهار 1394، صفحه 25-34.
[10] P. Sammartino and C. Baker, “Developments in the Frequency Diverse Bistatic System,” in Radar Conference, 2009 IEEE, pp. 1–5, IEEE, 2009.
[11] P. Sammartino, C. Baker, and H. Griffiths, “Frequency Diverse MIMO Techniques for Radar,” IEEE Transactions on Aerospace and Electronic Systems vol. 49, no. 1 January 2013.
[12] Oppenheim, Alan V., Ronald W. Schafer, and John R. Buck. Discrete-Time Signal Processing. Upper Saddle River, NJ: Prentice Hall, 1999, p. 468.
 [13]Harris, Fredric J. "On the Use of Windows for Harmonic Analysis with the Discrete Fourier Transform." Proceedings of the IEEE®. Vol. 66, January 1978, pp. 51–8