TITLE:
A 2.4 GHz Switched Beam Antenna for Indoor Applications Using Angle of Arrival Estimation
AUTHORS:
Reham Elsamnty, Ahmed Mohamed Attiya, Esmat Abdel Fattah Abdallah, Abdel Hadi Ammar
KEYWORDS:
Indoor Communications, Switched Beam Antenna, Directional Microstrip Antenna, Slotted Patch Antenna, Radio-Positioning, AOA Estimation, CRB
JOURNAL NAME:
Open Journal of Antennas and Propagation,
Vol.4 No.3,
August
15,
2016
ABSTRACT: This study introduces a new design of planar antenna array for ISM band applications
at 2.4 GHz. This prototype is switched beam antenna, namely planar antenna
with four meandered slotted triangular elements (PAFMSTE), which is proposed for
wireless indoor applications. The Base Station (BS) equipped with this planar antenna
is preferred to be at the center position on the room ceiling to cover all sectors of
the room. It is designed to use four directional triangular elements arranged to form
a square planar antenna array. The PAFMSTE is used to obtain optimal directivity in
four directions in azimuth plane with 3 dB beamwidth of 90° at a specific orientation
of 30° in elevation plane. Switched parasitic technique is used to enable PAFMSTE to
steer a directional beam through four locations by using four PIN diodes switches.
The High Frequency Structure Simulator (HFSS) is used as an efficient simulation
tool to optimize the performance of the PAFMSTE antenna. The fabrication and
measurements of the PAFMSTE antenna are introduced. The proposed antenna enable
radio positioning via Angle of Arrival (AOA) information collected from nearby
devices. Then, the Cramér-Rao Bound (CRB) is presented for AOA estimation using
identically and equally spaced antenna elements. The CRB depends on the directivity,
where the maximum values of CRB are 1.35 × 10-3 and 8 × 10-3 at HPBW of 60° and
90°, respectively.