Mobile worldwide interoperability for microwave access (Mobile WiMAX) based on IEEE 802.16e is a standard designed for metropolitan area networks (MAN) that cover an area wider than that covered by local area networks. Commercial WiMAX services are already available in some countries and regions. Services in Japan are scheduled to start in 2009. Mobile WiMAX supports “one-cell frequency reuse,”...

Space–time adaptive processing (STAP) for airborne early warning radar has been a very active area of research since the late 1980’s. An airborne rectangular planar array antenna is usually configured into subarrays and then partial adaptive processing is applied to the outputs of these subarrays. In practice, three kinds of errors are often encountered, i.e., the array gain and phase errors ex...

The CHARA array is an optical/near infrared interferometer consisting of six 1-meter diameter telescopes with the longest baseline of 331 m. With high angular resolution, the CHARA array provides a unique and powerful way of studying nearby stellar systems. In 2011, the CHARA array was funded by NSF-ATI for an upgrade of adaptive optics systems to all six telescopes to improve the sensitivity b...

A practical normal-mode helical antenna array together with a new method for the compensation of mutual coupling effect is proposed for the efficient adaptive nulling of interferences in a mobile communication environment. The helical antenna array is shown to be able to generate deeper nulls than an equivalent monopole antenna array in the presence of mutual coupling effect. The helical antenn...

This paper presents practical design of a smart antenna system based on direction-of-arrival estimation and adaptive beamforming. Direction-of-arrival (DOA) estimation is based on the MUSIC algorithm for identifying the directions of the source signals incident on the sensor array comprising the smart antenna system. Adaptive beamforming is achieved using the LMS algorithm for directing the mai...

A robust beamforming with quadratic constraints, formulated as a semidefinite programming (SDP) problem, is proposed in this paper. With this formulation, the constraints on magnitude response can be easily imposed on the adaptive beamformer. And the non-convex quadratic constraints can be transformed into linear constraints. Therefore, the proposed method can be robust against the steering dir...

A COMBINED CHANNEL-MODIFIED ADAPTIVE ARRAY MMSE CANCELLER AND VITERBI EQUALIZER by Richard M Friedman In this thesis, a very simple scheme is proposed which couples a maximum-likelihood sequence estimator (MLSE) with a X-element canceller. The method makes use of the MLSE's channel estimator to modify the locally generated training sequence used to calculate the antenna array weights. This meth...

One of the research areas of the Signal Processing group at the Eindhoven University of Technology is in adaptive array signal processing. It is concerned with the application of adaptive signal processing techniques to the outputs of a spatially distributed array of sensors. The power of these techniques lies in the possibility of achieving improvements in directivity and measured Signalto-Noi...

A Kalman filter solution to active control and its fast-array implementation are provided. The adaptive control problem is formulated as a state-estimation problem and no interchanging of the adaptive filter and the secondary-path is imposed. Moreover, no estimate of the disturbance signal is needed, and we exploit the structure in the state–space matrices to derive a fast-array implementation....

This paper presents practical design of a smart antenna system based on direction-of-arrival estimation and adaptive beam forming. Direction-of-arrival (DOA) estimation is based on the MUSIC algorithm for identifying the directions of the source signals incident on the sensor array comprising the smart antenna system. Adaptive beam forming is achieved using the LMS algorithm for directing the m...