A simple cross correlation switched beam system (XSBS) for angle of arrival estimation

We propose a practical, simple and hardware friendly, yet novel and efficient, angle of arrival (AoA) estimation system. Our intuitive, two-phases cross-correlation-based system requires a switched beam antenna array with a single radio frequency circuitry, which is used to collect an omni-directional reference signal using a single element of the antenna array in the first phase. Our system applies energy detection on the collected reference signal to decide on the presence or absence of a transmitted signal. In the second phase, the system steers the main beam to scan the angular region of interest. The collected signal from each beam angle is cross correlated with the omni-directional reference signal to determine the angle of arrival of the received signal. The combined practicality and high efficiency of our system is demonstrated through performance and complexity comparisons with one of the literature's best performing multiple signal classification (MUSIC) algorithm. Our proposed AoA estimation system has a negligible root mean square error at signal to noise ratio level greater than -16 dB, which is very comparable to MUSIC. 2013 IEEE.Qatar National Research FundScopu

Design and Implementation of System Components for Radio Frequency Based Asset Tracking Devices to Enhance Location Based Services. Study of angle of arrival techniques, effects of mutual coupling, design of an angle of arrival algorithm, design of a novel miniature reconfigurable antenna optimised for wireless communication systems

The angle of arrival estimation of multiple sources plays a vital role in the field of array signal processing as MIMO systems can be employed at both the transmitter and the receiver end and the system capacity, reliability and throughput can be significantly increased by using array signal processing. Almost all applications require accurate direction of arrival (DOA) estimation to localize the sources of the signals. Another important parameter of localization systems is the array geometry and sensor design which can be application specific and is used to estimate the DOA. In this work, various array geometries and arrival estimation algorithms are studied and then a new scheme for multiple source estimation is proposed and evaluated based on the performance of subspace and non-subspace decomposition methods. The proposed scheme has shown to outperform the conventional Multiple Signal Classification (MUSIC) estimation and Bartlett estimation techniques. The new scheme has a better performance advantage at low and high signal to noise ratio values (SNRs). The research work also studies different array geometries for both single and multiple incident sources and proposes a geometry which is cost effective and efficient for 3, 4, and 5 antenna array elements. This research also considers the shape of the ground plane and its effects on the angle of arrival estimation and in addition it shows how the mutual couplings between the elements effect the overall estimation and how this error can be minimised by using a decoupling matrix. At the end, a novel miniaturised multi element reconfigurable antenna to represent the receiver base station is designed and tested. The antenna radiation patterns in the azimuth angle are almost omni-directional with linear polarisation. The antenna geometry is uniplanar printed logspiral with striplines feeding network and biased components to improve the impedance bandwidth. The antenna provides the benefit of small size, and re-configurability and is very well suited for the asset tracking applications