In this paper, a low proﬁle extremely wideband printedmonopole antenna is presented. The pro- posed antenna operates over the LTE700/GSM800/900, GPS L1/GSM1800/1900/UMTS/IMT2100/Wi- Fi/LTE2300/2500, and WiMAX frequency bands based on − 6 dB reﬂection coeﬃcients. The simulated and measured results are found in good agreement. The conﬁguration of the proposed antenna consists of two strips named as coupling strip and shorted radiating strip at top of the substrate, whereas me- andered parasitic strip at bottom of the substrate. The bottom meandered strip helps in widening the overall operating bands by increasing the capacitance between the main radiating strip and meandered parasitic strip. Due to the capacitive coupling between the top and bottom elements, capacitance comes into the picture. The proposed antenna is elaborated through S -parameters analysis including typical shape parameters, surface current distributions, and radiation performances. Further, study is carried out in the vicinity of the mobile environment and user proximity. SAR is also calculated, and the results are found within the standard limit. The antenna conﬁguration, results and discussion are presented in the following sections.
In the last decades, wireless communication systems have been developed rapidly. The integration of several communication standards into a single system has become a trend. Now the most popular designs focus on wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) operations. As one of the most important devices, multi-band antenna has attracted much interest. To cover desirable bands and reduce the size, various promising antennas, such as printedmonopole antenna [1–5], CPW-fed antenna [6, 7], slot antenna [8–10], inverted-F antenna , have been proposed. For example, an printedmonopole antenna of size of 38 × 25 mm 2 was developed in , its
a wide impedance bandwidth and can be applied to various wireless communication systems such as 2.4/5.2/5.8 GHz WLAN and 2.5/3.5/5.5 GHz WiMAX. Furthermore, they also have the advantages of low profile, simple structure, easy fabrication, and good monopole- like radiation pattern. Many dual-wideband and wideband printedmonopole antennas have been proposed in [1–7] for WLAN and WiMAX applications. However, when these antennas are used in WLAN and WiMAX systems, additional band pass filters are required to avoid collision and minimize frequency interference because their wide operating bands cover many existing narrowband services. Many tri-band antennas have been proposed for WLAN and WiMAX applications in literatures [8–15], which have the better rejections in the undesired bands in comparison with wideband antennas. A paw-shaped antenna in , a wide-slot antenna with two pairs of inverted L-strips in  and a T-shaped antenna with two parasitic elements in , they create three operating bands by applying three different resonant lengths. In addition, another method to create three operating bands by introducing two notched bands in a wideband antenna is applied in [11–15]. Many methods have been introduced to reject the dispensable bands, such as inserting the strip in the slot  or on the radiating patch [13, 15], etching the slot on the radiating patch [12, 14] or on the ground plane [11–13], and embedding the parasitic strip .
In this paper, a novel butterfly shaped printedmonopole antenna for UWB short-range wireless communications has been presented. The proposed antenna prototype has been designed, fabricated and tested. Both calculated and measured results show that the proposed antenna has a broadband matched impedance band with almost constant gain. The proposed antenna has an impedance bandwidth of about 7.8 GHz from 3 GHz to 10.8 GHz covering the whole UWB frequency band. Also, the effect of antenna parameters on the antenna performance has been addressed. The antenna also has a good E- and H-plane radiation patterns through the entire UWB frequency band. By embedding a slit ring resonator (SRR) element in the feedline, a frequency band notch has been created which enables avoiding the interference with the existing WLAN systems. From these results, it is confirmed that the proposed antenna is a good candidate for UWB short-range wireless communication applications.
In this paper, a novel small ultra-wideband (UWB) printedmonopole antenna, designed to operate in 3.1-10.6 GHz frequency band, is presented. The antenna is composed of five non-overlapped rectangular patches, a partial ground plane and a standard 50-Ω microstrip feed line. The overall size of the proposed antenna is 22.8 mm 29.5 mm 0.813 mm. The design procedure that we have used is based on a mixed integer genetic algorithm (GA) and the finite-difference time-domain (FDTD) method with uniaxial perfectly matched layer (UPML) absorbing boundary condition. The optimized printedmonopole antenna is analyzed using our own FDTD code and the high frequency structure simulator (HFSS).
Abstract –Empirical results of an electrically small printedmonopole antenna is described with fractional bandwidth of 185% (115 MHz–2.90 GHz) for return-loss better than 10 dB, peak gain and radiation efficiency at 1.45 GHz of 2.35 dBi and 78.8%, respectively. The antenna geometry can be approximated to a back-to-back triangular shaped patch structure that is excited through a common feed-line with a meander-line T-shape divider. The truncated ground-plane includes a central stub located underneath the feed-line. The impedance bandwidth of the antenna is enhanced with the inclusion of meander-line slots in the patch and four double split-ring resonators on the underside of the radiating patches. The antenna radiates approximately omnidirectionally to provide coverage over a large part of VHF, whole of UHF, entire of L-band and some parts of S-band. The antenna has dimensions of 48.32×43.72×0.8 mm 3 , which is corresponding with the
A Printedmonopole antenna was designed and manufactured with the wideband performances in two frequency bands. The antenna is compatible with WiMAX and WiFi standards. After reviewing a couple of literatures, the antenna was designed, analyzed and proven for two central frequencies, 2.5 GHz and 5.6 GHz, with much improved bandwidths. Finally, the antenna was manufactured with the overall size of 4 cm × 4.4 cm on Rogers (RO4003) substrate. The antenna is made into three L-shaped radiators. A 50 Ω microstrip feed line connects the port to the two L-shaped radia- tors of different lengths, thus providing two frequency bands. An inverted L-shaped radiator is printed on the less radiation upped side, to tune the antenna for wide band performances. The raised problem was solved with the integral equation solver of the Ansoft high frequency simula- tor structure (HFSS-IE). Optimal results are presented in this article: the simulation results in comparison with measured results. This antenna prototype’s overall dimensions would be read- justed according to any industrial and manufacturing requests.
ABSTRACT: This project introduces a slot loaded CPW feed ultra wideband (UWB) printedmonopole antenna (PMA) with dual band notched characteristics. The antenna uses three rectangular slots to create dual band notched characteristics in WLAN and uplink and downlink of X-band satellite communication. The proposed antenna has novel suitability to utilize it for both uplink and downlink satellite communication band notching applications. It has the characteristics of less compact in size with VSWR less than two. Micro strip have attractive merits such as compact size, low-cost, ease of fabrication, wide impedance bandwidth and good Omni-directional radiation that make it favorite for UWB applications. In recent years researchers have improved various challenges of UWB antennas like impedance, band-width, radiation patterns, matching characteristics and size of antennas. But UWB systems are highly sensitive to electromagnetic interferences with existing narrow -band wireless communication systems. Hence it is necessary to design antennas with multiband filtering characteristics to avoid interferences.
Several approaches been proposed to achieve band-notched characteristic. As for PMAs, there are two most conventional approaches: One is to etch various shaped slots or slits in the radiating patch [5, 6], the feedline [7, 8] or the ground plane [9, 10]. Alternative approach is to introduce parasitic elements beside the printedmonopole [11–13] or the feedline [14, 15]. It is well known that the ultrawideband properties of PMAs can be attributed to several adjacent resonance modes . Band-notched structure can be regarded as an additional embedded resonance mode which disturbs the inner EM field of the original antenna body at the notched frequency. As a result,the antenna input impedance is shifted to a very high or very low level. From the angle of transmission line model, the antenna here acts as a virtual-open or virtual-short circuit which brings out impedance mismatch at the feed point.
Abstract—A novel ultra-wideband (UWB) printedmonopole antenna with triple band-notched characteristics is proposed in this paper. The antenna bandwidth is extended by grooving on the connecting ﬂoor and increasing the impedance transformation line, with antenna bandwidth of 3.0 ∼ 11 GHz and relative bandwidth of 114%. The overall antenna size is 35 × 30 mm 2 . The complementary split-ring resonators (CSRRs) are loaded on the UWB antenna patch with microstrip wire feed. A symmetric J gap is loaded on the bottom plate, and the spiral gap is loaded on the feeder. The triple band-notched characteristics at 3.22 ∼ 3.97 GHz, 4.94 ∼ 5.84 GHz, and 7.25 ∼ 7.86 GHz bands are realized. The gain of the designed antenna in the notch frequency segment can be reduced rapidly to − 4 dbi, while the gain of other frequency bands is above 2 dBi. Simulated and measured results show that the antenna has stable gain and good radiation characteristics in the UWB frequency range.
Abstract—Major challenges faced by airborne VHF monopole antennas are to achieve wideband characteristics in permissible antenna height and to ﬁnd the apt location for mounting, so as to satisfy suﬃcient ground plane around its feed point. The increased applications of electromagnetic spectrum result in a large number of antennas competing in the limited space available on platform. The asymmetries and curved surfaces on the platform as well as the limited size of the available ground plane may result in an insuﬃcient ground plane for these antennas on platform. The deﬁcient ground plane can deteriorate the radiation characteristics of antenna. Printedmonopole antenna, which does not require a backing ground plane, can overcome this deﬁciency, as the ground planes of these antennas are implemented in the same plane as that of the radiating element. This paper proposes a wideband printedmonopole VHF antenna for airborne applications which simultaneously achieves reduced height and reduced ground plane on platform. The antenna has a size of 0 . 1045 λ× 0 . 1272 λ× 0 . 072 λ , where λ is the free space wavelength at lowest frequency of operation, and it achieves a 3 : 1 VSWR bandwidth of 38%. The radiation characteristics and size of the proposed antenna are comparable to the conventional airborne blade monopole antenna with the added advantage of requiring minimal ground plane to mount on.
The wireless communication technology has seen extremely rapid growth, and wireless networks play a crucial role for wireless handheld devices. The integrated antennas in such devices should be able to cater the need for acceptable gain and impedance bandwidth. Through Joint Research Center (JRC) reference report, European commission provided guidelines for conducting a cost-beneﬁt analysis of smart grid projects. The report has convincingly argued the economic potential of the smart grid systems . LR-WPAN, IEEE 802.15.4 protocol, can provide high energy eﬃciency and higher node- living time due to optional beacon-enable mode. Unlike Wireless LAN standard, LR-WPAN standard needs very little or negligible infrastructure for connections. There is no need of connectivity beyond the communication link established between two devices. The LR-WPAN has higher eﬃciency due to lower latency rates and higher node-living time. Hence, LR-WPAN oﬀers power eﬃcient and low cost solutions . The Industrial, Scientiﬁc, and Medical (ISM) band in European countries covers a range of Low Rate Wireless Personal Area Network applications at 868.3 MHz. LR-WPAN communication applications are able to support smart grid networks with higher accuracy, lower latency and high node-living time. In addition, LR-WPAN conﬁgured for wireless sensor networks has higher power eﬃciency than simple sensor nets . Printedmonopole antennas are being extensively utilized for handheld communication devices such as tablet, laptops and mobile phones [4–8]. The printedmonopole antenna operational at multiple resonant modes is being excessively utilized as embedded antennas in handheld devices for end-user applications. The antennas can be tuned for target applications without major modiﬁcations in substrate dimensions or eﬀective antenna size. The resonant modes can be excited by modiﬁcation or addition of monopole branches. The electrical size of such an antenna is always of great concern. The loop antennas etched on substrate or base of handheld devices oﬀer an
Abstract—In this paper, a compact printedmonopole antenna with periodic H-shaped slots for WLAN application is proposed, designed, and fabricated with standard ﬂexible printed circuit board process. By cutting four H-shaped slots in the radiation patch of the printedmonopole antenna, the resonant frequency of the monopole antenna can be reduced; therefore, a compact antenna is realized. The radiator size of the antenna is 0 . 07 λ g × 0 . 19 λ g , which is much smaller than that of a traditional printed
has been widely studied [3–8] due to its alluring merits. Printedmonopole antenna is a printed type of antenna consisting of a dielectric substrate sandwiched in between a finite ground plane and a patch. The size of ground plane also determines the bandwidth, gain and return loss of the antenna [9–12]. The bandwidth could also be increased by creating some slots on the patch or ground plane . This way may produce wider bandwidth because it make irregular current surface on the patch and ground plane.
To understand the operation mechanism of the complementary co-directional SRRs simulated surface current distribution at notched frequency 3.9 GHz and 5.7 GHz of the proposed antenna is shown in Fig. 3 (a) and (b), respectively. When the antenna is working at the central notched band frequency at 3.9 GHz, the outer complementary SRR behaves as a separator as shown in Fig. 3 (a), which almost has no relation to the other band-notches. Similarly, the inner complementary SRR operates as a second separator for the central notched band frequency at 5.7 GHz as shown in Fig. 3 (b). It can be seen from figure that the surface currents are highly concentrated around the outer and inner complementary SRRs at 3.9 GHz and 5.7 GHz, respectively. It means that the energy is stored around the individual complementary SRR and the proposed antenna does not radiate into the air. Thus, the proposed complementary co-directional SRRs loaded printedmonopole antenna reject dual notched stop bands for WiMAX and WLAN bands.
 Mallahzadeh, A.R.; Seyyedrezaei, S.F.; Ghahvehchian, N.; Nezhad, S.M.A.; Mallahzadeh, S, “Tri-band printedmonopole antenna for WLAN and WiMAX MIMO system” in Antennas and Propagation (EUCAP), Proceedings of the 5th European Conference on 2011. Pp548-551
Very recently, a few novel antenna designs are presented for the aforementioned, narrow-bezel notebook applications [4–7]. These designs include the uses of slot antennas , short-circuited monopole antennas , loop antennas [6, 7], and require antenna heights of no more than 5 mm. However, the drawback of these antennas is that the required, minimum lateral length is at least greater than 20 mm. For Gbps communications in the near future, multiple WLAN antennas are expected to be embedded in the notebook computers. Accordingly, new design considerations for notebook antennas to acquire a low proﬁle of 5 mm and a small lateral length are becoming substantially important. To fulﬁll these new requests, a very-low-proﬁle, small-sized printedmonopole antenna is proposed in this paper.
In this paper, a penta-band E-shaped printedmonopole antenna suitable for MIMO applications is proposed. By introducing resonance paths on the vertical arm of the E-shaped antenna, which is carried out through insertion of slots and stubs, ﬁve separate resonance bands can be obtained from the antenna at the frequencies of 2.1, 2.5, 3.5, 5.2 and 5.8 GHz. The various conﬁgurations of such antennas in relation to each other are investigated and based on the least correlation, mutual coupling and optimal radiation patterns the most suitable conﬁguration for MIMO application is presented. Simulation results via software package HFSS and measured results are compared and discussed. 2. GENERATION OF RESONANCE FREQUENCIES
The purpose of this study is to design a new printedmonopole antenna that not only preserves a large operation bandwidth but also reduces antenna size that is comparable to those of planar antennas in Table 1. This article proposes a new coplanar meander loop monopole antenna with a step-shaped ground plane, which has an area of 15 × 170 mm 2 and bandwidth of 550 MHz (2.5 : 1 VSWR) for
Several techniques in the geometry have been proposed in literature to achieve super wideband performance. SWB antennas have been implemented in different configurations such as metal plate monopoles, printed monopoles and printed slot antenna configurations as reviewed by Zhong S. et.al. . Printed monopoles and printed slot antenna configurations have been preferred due to their compactness and easier integration. The super-wideband antennas reported in – have dimensions which correspond to the lower frequency bound from 0.4 GHz to 1.3GHz. To achieve increased bandwidth, the thinner substrate used in these antennas has lower permittivity. In  an SWB antenna have been reported with complex fractal patch geometry on thinner and lower dielectric permittivity substrate which have lower bound frequency near 2GHz and subsequent reduction in size. On the same type of substrate, a tapered microstrip fed circular ring radiating patch with round cornered ground plane has been implemented in  to obtain a lower bound frequency of 1.6 GHz. A SWB antenna on FR4 substrate have been reported in  with an offset fed egg shaped patch having fractal ground plane and in  with a microstrip fed clover shaped radiating patch. Using the same substrate and co-planar waveguide (CPW) feed, a partially egg shaped slot antenna  and a fractal radiating patch antenna  has also been reported.