In this paper, we consider the use of Compaq iPAQ 3760s, equipped with a built-in microphone and an external wireless card, for acoustic acquisition and processing to perform a distributed acoustical beamforming. Time synchronization among the microphones is achieved by the ReferenceBroadcast Synchronization method. Two beamforming algorithms, based on the time difference of arrivals (TDOAs) am...

In this paper, the performance of cognitive radio (CR) code divisionmultiple access (CDMA) networks is analyzed in the presence of receive beamforming at the base stations (BSs). More precisely, we analyze, through simulations, the performance achievable by a CR user, with and without spectrum sensing, in a three-cell scenario. Uplink communications are considered. Three different schemes for s...

In this chapter, we describe a compact array antenna. Beamforming is achieved by tuning the load reactances at parasitic elements surrounding the active central element. The existing beam forming algorithms for this reactively controlled parasitic array antennas require long training time. In comparison with these algorithms, a faster beamforming algorithm, based on simultaneous perturbation st...

One of the most challenging problems in recent antenna engineering fields is to achieve highly reliable beamforming capabilities in an extremely restricted space of small handheld devices. In this paper, we introduce a new perspective on single-radiator multiple-port (SRMP) antenna to alter the traditional approach of multiple-antenna arrays for improving beamforming performances with reduced a...

In this paper, we investigate broadband OFDM systems which apply beamforming in combination with different space–time diversity techniques. Various beamforming scenarios with transmitter and/or receiver sided beamforming are considered. Space–time diversity is obtained by cyclic delay diversity (CDD) in order to artificially shape the spectrum of the received signal. Thus, an advantageous distr...

Abstract: This study aims to generate a model for the problem of beamforming in fractional Fourier domain, through which a general solution for obtaining weighted beamforming in fractional Fourier domain for different criteria might be delivered. In order to generate this model, a description of fractional delay concept is presented, through which the string vector in fractional Fourier domain ...

In this paper we introduce a polynomial filter structure for filterand-sum beamforming applied to microphone array application. The structure is a multi-dimensional extension of well-known Farrow structure, which has mainly been used for fractional delay filtering and interpolation of 1-D signals. The proposed method enables an easy, smooth, and efficient control of beamforming filter character...

Hybrid analog-digital beamforming design based on the channel state information (CSI) for wideband millimeter wave channel models receives attention in recent years. However, without the CSI, most previously proposed beamforming methods, such as singular value decomposition (SVD)-based ones, are almost infeasible due to the complexity of both the channel estimation and SVD for large antenna arr...

This paper considers interference limited communication systems where the desired user and interfering users are symbol-synchronized. A novel adaptive beamforming technique is proposed for quadrature phase shift keying (QPSK) receiver based directly on minimizing the bit error rate. It is demonstrated that the proposed minimum bit error rate (MBER) approach utilizes the system resource (antenna...