Smart antenna (or directional antenna) technology has been developed recently, which can control its antenna beam pattern to a specified direction by software. Medium access control (MAC) protocols using smart antennas, called directional MAC protocols, have the following potentials: higher spatial reuse, larger extension of communication range, less interference and higher total throughput com...

Increasing spatial reuse of spectrum is fundamental to improving the capacity and usefulness of large wireless networks. Steerable and adaptive antennas facilitate reuse, and a number of MAC-layer protocols have been developed for them. Existing protocols, however, do not allow the MAC (or scheduling) process to fully consider the capabilities of antenna reconfiguration, or vice-versa. Without ...

A wireless sensor server is developed based on a reconfigurable active smart-antenna/retrodirective array. The system can serve as both a retrodirective array transponder and a smart-antenna receiver simply by changing the frequency of the local oscillator applied to the mixers, enabling it to best utilize its hardware to suit its communication environment. When operating as a direct-conversion...

This chapter unifies the principles and analyses of conventional signal processing algorithms for receive-side smart antennas, and compares their performance and numerical complexity. The chapter starts with a brief look at the traditional single-antenna optimum symbol-detector, continues with analyses of conventional smart antenna algorithms, i.e., statistical beamforming (BF) and maximal-rati...

Firstly, this paper researches on the scheme of amplitude weighting(AW) for smart antenna(SA) beamforming in linear array. With the proposed mathematical model in this paper, QPSK base-band AW is an effective method for linear SA to realize multi-user and multi-direction transmission, by which the perfect directional beam-forming can be realized with low complexity and low cost. Secondly, this ...

A new interference estimation technique is proposed for the deployment of a smart-antenna-equipped MANET (Mobile Ad hoc NETwork), acting as a secondary network, sharing the same scarce frequency band as many legacy fixed antennas (primary network) in the same area. With the help of only a coarse probabilistic estimate of each primary antenna location, the MANET can voluntarily overestimate the ...

The main objective of this paper is to develop a new software testbed to aid our research on various smart antenna (SA) technologies proposed for future generation wireless communication systems. These models can be used as a platform to test the use of DSPs/FPGs in new generation CDMA-SA systems and will allow to evaluate the array pattern (AP) and the Bit Error Rate (BER) performance over a r...

We propose a downlink multiple-input multipleoutput (MIMO) multi-carrier code division multiple access (MCCDMA) system with adaptive beamforming algorithm for smart antennas. The algorithm used in this paper is based on the Least Mean Square (LMS), with pilot channel estimation (PCE) and the zero forcing equalizer (ZFE) in the receiver, requiring reference signal and no knowledge channel. MC-CD...

To support high data rate wireless communications, in this paper, based on the linearly constrained constant modulus (LCCM) criterion, the reverse link performance of the multi-carrier code division multiple access (MC-CDMA) receiver, with frequency combiner, and having smart antenna arrays beamformer in base station, has been investigated over the Rayleigh fading channel. By using the Kronecke...

Over the last few years, wireless cellular communications has experienced rapid growth in the demand for provision of high data rate wireless multimedia services. This fact motivates the need to find ways to improve the spectrum efficiency of wireless communication systems. Smart or adaptive antennas have emerged as a promising technology to enhance the spectrum efficiency of present and future...