Compact dual‐band printed quadrifilar helix antenna for practical hand‐held devices

Abstract

This paper proposes a compact dual-band printed quadrifilar helix antenna (QHA) operating at GPS-L1 (1575 ± 2 MHz) and L2 (1228 ± 2 MHz) bands. To generate the dual operating bands, two interconnected lines with unequal lengths are introduced as a radiating element. The closely allocated radiators resonate in quarter-wavelength mode, which significantly miniaturizes antenna's size. Four shunt capacitors are loaded near ports to manipulate the mutual coupling between each two radiators, so that satisfactory matching condition with minimum active reflection at two target bands can be obtained simultaneously. Then, a compact feeding network consisting of on-chip hybrid couplers is designed and connected to the QHA. Measured results show that the compact proposed antenna achieves peak gains of 1.5 dBic and 2.6 dBic at 1575 MHz and 1228 MHz, respectively. The axial ratios (ARs) at L1 and L2 bands are both below 2.5 dB, and the half-power-beamwidths (HPBWs) are as wide as 130 and 116 , respectively. As compared with reported works, the proposed antenna can achieve much more compact size (0.11 × 0.21 λ 0 2) and dual-band radiation at the same time.

Investigation of a defected ground structure inspired wideband printed monopole mobile antenna using characteristics mode analysis

“…Later, the SAR of the proposed monopole antenna is interpreted using the 3D voxel human phantom head and hand model in Computer Simulation Technology (CST) Studio Suite. The comparison of performance metrics (which includes idea about the antenna configuration, band coverage, SAR analysis and CMA investigation) of proposed antenna with existing ones [1][2][3][4][5][6][7][8][9][10][11][12][13][14] are presented in Table 1, that confirms its significance over others. To explore insights about the antenna, the CMA is vividly studied on its different structural configurations to predict modal resonance characteristics.…”

“… Note : Coverage of Bands: GSM 900, LTE, Wi‐Fi, WiMAX, ISM, 5G (5 GHz), n77, n78, LTE Band 46 and WLAN (IEEE 802.11 b/g/n), References 1–14 comes the under the category of partially coverage of the designated bands. …”

“…In general, there is a huge demand of compact multi-resonant mobile antennas in various domains of cellular communications. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] In practical scenario, it is seen that separate antenna modules operating in different mobile bands (sub-6 GHz) has swamping effects of stronger signals coming out from different antennas, often resulted in the frequent RF droppings. Hence, RF device engineers have to come up with a solution to integrate multi-resonant modes into a single design entity.…”

“…With the presence of such ambient RF signals in the environment, they are considered as the intrinsic part of wireless platforms. In general, there is a huge demand of compact multi‐resonant mobile antennas in various domains of cellular communications 1–14 . In practical scenario, it is seen that separate antenna modules operating in different mobile bands (sub‐6 GHz) has swamping effects of stronger signals coming out from different antennas, often resulted in the frequent RF droppings.…”

A Printed Antenna Design with Defected Ground Structure for Multiband Applications

“…Each wireless system requires a large impedance bandwidth and a stable radiation pattern over its operating frequency range. The multiband antenna designs, which published in wireless communications are heading towards covering more than one resonance frequency band like the dual band [1], the triple band [2], [3], and quad band applications [4], [5]. On the other hand, printed antennas are popular candidates for providing multiband characteristics due to the lightweight features, low cost, and easy fabrication [6].…”