Dielectric-loaded trapezoidal toothed log-periodic antenna

Abstract

In this article, dielectric‐loaded metal trapezoidal toothed log‐periodic antenna (TTLPA) is described. The dielectric material, Rogers RT/duroid 6010 (εr = 10.2, tan δ = 0.0023) of thickness = 5 mm and of same shape as TTLPA is placed on top of conventional metal TTLPA which provides enhanced bandwidth and/or miniaturizes its aperture size without degradation in gain. The dielectric loading increases the effective length of antenna, and therefore, extends its operating frequency towards lower frequency side which miniaturizes aperture cross‐section of antenna with slight increase in its thickness. The simulated input and radiation characteristics of TTLPA without and with dielectric loading are compared. The comparative studies show that the proposed antenna is 38.78% smaller in respect of aperture cross‐section as compared with conventional antenna having almost identical bandwidth of 8.6 GHz (2.2–10.8 GHz) and gain variation over the range 1.5–6.1 dBi. The proposed antenna of aperture size 48.9 × 48.9 mm2 provides −10 dB reflection coefficient bandwidth of 8.6 GHz (2.2–10.8 GHz) and gain variation in the range 1.3–5.7 dBi whereas the conventional antenna of same aperture size achieves somewhat reduced bandwidth of 7.6 GHz (3.2–10.8 GHz) and gain variation in the range 1.6–5.0 dBi over the operating frequency range.

Bandwidth Enhancement of Trapezoidal Toothed Log-Periodic Antenna Using Slot Configuration

“…The detailed design optimum dimensions of antenna as well as balun (i.e. microstrip-to-coplanar stripline transition) can be found in [3]. For dielectric loading, a 5 mm thick Rogers RT/duroid 6010 having relative permittivity of 10.2 and loss tangent of 0.0023 is used.…”

“…Therefore, increment in elements size or modifications in antenna geometry becomes necessary for bandwidth improvement and/or size reduction of such antennas. However, the concept of dielectric loading is utilized for bandwidth improvement of metal TTLPA without disturbing the geometry and dimensions [3]. The dielectric-loaded TTLPA (DLTTLP) is efficient for bandwidth enhancement and/or size miniaturization but the radiation pattern distorts.…”

“…Fig.1Trapezoidal toothed log-periodic antennas: a geometrical dimensions, b metal TTLPA, and c dielectric-loaded TTLPA[3] …”

Ultra-Wideband Trapezoidal Log-Periodic Antenna Integrated with an Elliptical Lens

“…In [21], a trapezoidal toothed LPA with a microstrip line (MSL)-to-coplanar stripline (CPS) balun was proposed for L-band and S-band applications. In [22], a dielectric slab was loaded on a trapezoidal toothed LPA for bandwidth enhancement and miniaturization, and the antenna gain was improved to 6.1 dBi. However, the reported antennas typically suffered from bandwidth limitations caused by the feeding methods.…”

“…A coaxial feeding used in [19,20] compromised the biggest advantage of the trapezoidal LPA. A perpendicular CPS was used to feed a trapezoidal LPA in [21,22]. However, the perpendicular feeding also restricted the operating bandwidth and resulted in bulkier non-planar antenna structures.…”