Smart antennas for wireless communication systems

Akıllı antenler, kablosuz haberleşme sistemlerinin performanslarını artıracak son temel teknolojik buluşlar arasında yer almaktadır. Bir akıllı anten dizisi, uyarlanabilir olarak gelen sinyali işleyerek gezgin iletişim kanalının uzaysal yayılım alanını en verimli biçimde kullanmayı amaçlayan birçok anten elemanından oluşur (1). Genellikle farklı anten elemanlarından alınan sinyaller karmaşık w ağırlık katsayısı ile çarpılır ve toplanır. Buradaki ağırlık katsayıları her iterasyon adımında değiştirilerek alınır. Antenin kendisi değil ama sinyal işleme kabiliyetine sahip olan anten sistemi sayesinde "uyarlanabilir" olarak adlandırılan katsayı seçimi olur (2). Akıllı olan sadece anten değil o antenin de içinde bulunduğu anten sistemi akıllı olarak adlandırılır.

Kablosuz haberleşme sistemleri için akıllı antenler

Smart antennas are considered to be promising technology for increasing the performance of wireless communication systems. A smart antenna consists of several antenna elements, whose signals are processed adaptively in order to exploit the spatial domain of the mobile radio channel (1). Usually, the signals received at the different antenna elements are multiplied with complex weights w, and then summed up; the weights are chosen adaptively. Not the antenna itself, but the whole antenna system including the signal processing is called "adaptive" (2). Only the antenna is not smart, the antenna system which contains also antenna elements is called smart.

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