SCIENCE CHINA
Technological Sciences
© Science China Press and Springer-Verlag Berlin Heidelberg 2010 tech.scichina.com www.springerlink.com
*Corresponding author (email: ghzhao@mail.xidian.edu.cn)
• RESEARCH PAPER •
September 2010 Vol.53 No.9: 2581–2588
doi: 10.1007/s11431-010-4025-1
Angel estimation via frequency diversity of the SIAR radar
based on Bayesian theory
ZHAO GuangHui
*
, SHI GuangMing & ZHOU JiaShe
Key Laboratory of Intelligent Perception and Image Understanding of Ministry of Education of China,
Xidian University, Xi’an 710071, China
Received June 11, 2009; accepted May 4, 2010
The orthogonal signals of multi-carrier-frequency emission and multiple antennas receipt module are used in SIAR radar. The
corresponding received echo is equivalent to non-uniform spatial sampling after the frequency diversity process. As using the
traditional Fourier transform will result in the target spectral with large sidelobe, the method presented in this paper firstly
makes the preordering treatment for the position of the received antenna. Then, the Bayesian maximum posteriori estimation
with l
2
-norm weighted constraint is utilized to achieve the equivalent uniform array echo. The simulations present the spectrum
estimation in angle precision estimation of multiple targets under different SNRs, different virtual antenna numbers and dif-
ferent elevations. The estimation results confirm the advantage of SIAR radar both in array expansion and angle estimation.
synthetic impulse and aperture radar, Bayesian maximum posteriori probability formulation, frequency diversity,
l
2
-norm weighted constraint
Citation: Zhao G H, Shi G M, Zhou J S. Angel estimation via frequency diversity of the SIAR radar based on Bayesian theory. Sci China Tech Sci, 2010, 53:
25812588, doi: 10.1007/s11431-010-4025-1
1 Introduction
In recent years, multiple-input multiple-output (MIMO)
radar [1–6] based on multi-sensor data and information fu-
sion has developed rapidly. Although the concept of MIMO
radar was proposed in recent years, intensive research has
conducted on synthetic impulse and aperture radar (SIAR)
at home and abroad [7–9]. This kind of radar system con-
tains the idea of the multiple transmitters and multiple re-
ceivers [2]. A series of orthogonal frequency codes, viz.
signals with different carrier-frequencies, are emitted by
different antennas during the individual transmitting period,
which brings great advantage in radar detection and
high-resolution spectrum estimation.
When dealing with the coherent echo model, the conven-
tional spectrum estimation and the super-resolution algo-
rithms such as MUSIC method [10], ESPRIT method [11]
and other spatial characteristics based on subspace eigen-
value decomposition method may face the phenomena of
declining the effective antenna aperture and expanding the
beam-width, which will decrease the resolution in angle
estimation. Therefore, how to effectively broaden the array
aperture becomes a major hot spot in array signal pro-
cessing. Most of the traditional virtual array expanding is
based on the theory of the high-order cumulant, and such
high-order statistic characteristic not only characterizes the
amplitude information but also describes the phase infor-
mation. Also it is not sensitive to any type of Gaussian pro-
cess and can effectively explore the non-Gaussian compo-
nents while restrains the Gaussian noise to the most extent.
Dogan and Mendel [12] pointed out that the fourth-order
cumulant has the ability of the array synthesis without any
direction information loss, and the proposed the virtual cor-