A Port and Frequency Reconfigurable MIMO Slot Antenna for WLAN Applications

IEEE Trans. Antennas Propagat.

Shamim

2018

103

Abstract-This paper presents a novel integrated antenna system for cognitive radio (CR) applications. The design consists of a compact 4-element reconfigurable annular slot based multiple-input-multiple-output (MIMO) antenna system integrated within an ultra-wide-band (UWB) sensing antenna. All the antenna elements are planar in structure and designed on a single substrate (RO-4350) with dimensions 60×120×1.5 mm 3 . The frequency reconfigurable slot based MIMO antenna system is tuned over a wide frequency band from 1.77 GHz to 2.51 GHz while the UWB sensing antenna is covering from 0.75∼7.65 GHz The proposed antenna system is suitable for CR enabled wireless devices. The envelope correlation coefficient (ECC) did not exceed 0.248 in the entire operating band of the MIMO antenna part. The maximum measured gain of the MIMO antenna is 3.2 dBi with maximum efficiency of 81%.

Section: Introductionmentioning

confidence: 99%

An Integrated Four-Element Slot-Based MIMO and a UWB Sensing Antenna System for CR Platforms

IEEE Trans. Antennas Propagat.

Shamim

2018

103

“…The proposed design was covering three widebands: R. Hussain Several MIMO reconfigurable antenna designs were reported in literature for CR applications with wide tuning bands [9]- [15]. In [12], a 2-element frequency agile MIMO slot antenna was presented. The given antenna was covering several frequency band: 2.4∼2.5 GHz, 4.9∼5.725 GHz and 4.9∼5.725 GHz.…”

Section: Introductionmentioning

confidence: 99%

4-Element Concentric Pentagonal Slot-Line-Based Ultra-Wide Tuning Frequency Reconfigurable MIMO Antenna System

IEEE Trans. Antennas Propagat.

Shamim

2018

Abstract-In this paper, a novel, compact, ultra-wideband tuning, concentric pentagonal slot-line-based frequency reconfigurable multipleinput-multiple-output (MIMO) antenna system is presented. It consists of a 4-element antenna design on a commercially available FR-4 substrate with dimensions 60×120×1.56 mm 3 . All the antenna elements are planar in structure that are etched out from ground (GND) plane. Frequency reconfigurability is achieved using varactor diodes by reactively loading the antennas. Each capacitance value of the varactor diode results in triband operation. Proper capacitive reactance loading enables the antenna to resonate over a wide frequency band. The proposed MIMO antenna system is tuned over an ultra-wide frequency band and a smooth variation of the resonance frequencies is observed from 1.32∼1.49 GHz and 1.75∼5.2 GHz. Moreover, the unique feature of the proposed antenna system is the effectiveness of reactive loading the slot over all the resonating bands. The proposed antenna system is compact and suitable to be used in wireless handheld devices and mobile terminals for cognitive radio (CR) applications. The envelope correlation coefficient (ECC) did not exceed 0.186 in the entire operating band of the MIMO antenna operation. The maximum measured gain of the MIMO antenna is 4.5 dBi with maximum efficiency of 81%.

“…Few MIMO slot‐based antennas were presented in Refs. , while very few MIMO slot‐based frequency reconfigurable antennas appeared in the literature . In Ref.…”

Section: Introductionmentioning

confidence: 99%

“…In Ref. , a port reconfigurable MIMO slot antenna was presented that covered three frequency bands (2.4, 5, and 5.5 GHz). In Ref.…”

Section: Introductionmentioning

confidence: 99%

Analysis of slot-based radiators using TCM and its application in MIMO antennas

Ghalib

Int J RF Microw Comput Aided Eng

2018

In this article, with the help of the theory of characteristic modes (TCM), it is found that the introduction of circular slots in a chassis modifies the chassis modes. Based on the location of the slot, different chassis modes will be affected. For a fixed location, the slot to chassis size ratio plays an important role in its effect on the radiating bandwidth (BW). For a small size ratio, a modified chassis mode will be created without affecting the radiating BW. The current concentration across the slot depends on the shape of the slot (circular, rectangular, triangular, or square) and its location on the chassis. Moreover, the effect of multiple circular slots on the chassis modes is investigated. For slots introduced in a symmetrical fashion, that is, four elements, the modes are not affected and are similar to the original chassis ones. We also investigate the principle behind frequency reconfigurability using TCM analysis. The varactors used for frequency reconfigurability do not alter the radiating BW (Modal Significance plots) but only help in the input impedance matching at different frequency bands of the same mode. If a mode is excited purely using a proper feeding arrangement, the same frequency reconfigurable antenna will behave as a wide band one. Based on the detailed analysis presented in this work, a compact multiple‐input‐multiple‐output annular slot frequency reconfigurable antenna operating between 1.8 and 2.45 GHz is presented. Frequency tuning is achieved using varactor diodes.