نتایج جستجو برای: small antennas

تعداد نتایج: 800395  

2003
C. Waldschmidt C. Kuhnert S. Schulteis W. Wiesbeck

A model for an extended MIMO transmission channel including transmitter, receiver, antennas and the physical channel is presented. For the analysis of compact MIMO systems for small handheld devices, it is inevitable to consider this extended model, since the antennas couple and interact, which influences both SNR and the channel matrix H. Capacity calculations for diversity and beamforming bas...

Journal: :Ad Hoc Networks 2012
Robert Murawski Emad A. Felemban Eylem Ekici Sangjoon Park S. Yoo Kangwoo Lee Juderk Park Zeeshan Hameed Mir

Directional antennas offer many potential advantages for wireless networks such as increased network capacity, extended transmission range and reduced energy consumption. Exploiting these advantages requires new protocols and mechanisms at various communication layers to intelligently control the directional antenna system. With directional antennas, many trivial mechanisms, such as neighbor di...

Journal: :EURASIP J. Adv. Sig. Proc. 2011
Shun Kawakami Tomoaki Ohtsuki

In this paper, we propose a localization method using iterative angle of arrival (AOA) method sharing snapshots of coherent subarrays. The conventional AOA method is restricted in some applications because array antenna used for receivers requires many antennas to improve localization accuracy. The proposed method improves localization accuracy without increasing elements of antenna arrays, and...

Journal: :CoRR 2013
Tianyang Bai Robert W. Heath

Abstract—Massive multiple-input multiple-output (MIMO) is a transmission technique for cellular systems that uses many antennas to support not-as-many users. Thus far, the performance of massive MIMO has only been examined in finite cellular networks. In this letter, we analyze its performance in random cellular networks with Poisson distributed base station locations. Specifically, we provide ...

2007
Naoki Honma Riichi Kudo Kentaro Nishimori Yasushi Takatori Atsushi Ohta

Multi-Input Multi-Output (MIMO) technology, which employs several antennas, enhances wireless data transmission even with a limited bandwidth [1]. Considering a multiuser environment, the spatial multiplexing of several users, which is called multiuser MIMO (MU-MIMO), is more effective in enhancing the total data transmission ratio than single user MIMO [2]. Various types of MIMO antennas have ...

2013
Awanish kumar kaushik

this article presents an overview of the recent Frequency dependent and Frequency independent antenna theory. An antenna is defined by Webster’s Dictionary as “a usually metallic device (as a rod or wire) for radiating (transmitting) or receiving radio waves or EM wave.” The IEEE Standard Definitions of Terms for Antennas (IEEE Std 145–1983) defines the antenna as “a means for radiating or rece...

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