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In this paper, a planar antenna structure‐based compact high gain wideband antenna array is presented for 5G millimeter wave applications. The proposed array uses a 1‐to‐8 power divider to feed eight antenna elements arranged linearly. To enhance the gain, multiple slits and I‐slots are placed on the ground plane and feeding network, respectively. To further improve the gain of the design, an L‐shaped metallic reflector is positioned at the optimum distance. With a large 10 dB bandwidth of 35.93% from 22.6 to 32.5 GHz, the proposed antenna array operates in the two 5G bands of 26 GHz and 28 GHz. The proposed antenna array's measured gain varies from 9.18 to 13.22 dBi which is higher than the gain of 6.60–10.45 dBi of the unmodified array for the entire operating range. The antenna array shows a narrow beamwidth of 6.25° in its E‐plane and radiates in end‐fire direction. The overall dimension of the proposed antenna array is 57 mm × 25.978 mm × 0.787 mm, which features a simple, compact design. This antenna can be used for millimeter wave application as it fulfills all the requirements of future 5G applications at 26 and 28 GHz bands. [ABSTRACT FROM AUTHOR]

A dual-band high-gain linearly polarized antenna for wideband operation using a defective frequency selective surface (DFSS) is proposed and demonstrated experimentally. The designed antenna consists of radiating patch, truncated ground with a half-inverted L-shaped rectangular ring and frequency selective surface (FSS) with a defective ground plane. The dimensions are optimized to achieve dual band with a 10-dB impedance bandwidth of 7.72% from 2.37 to 2.56 GHz and 46.75% from 4.60 to 7.41 GHz. The antenna gain is enhanced by 8.8 dBi at lower band and 4.5 dBi at upper wideband. The maximum gain achieved using this technique is 8.8 dBi at 2.4 GHz. The measured and simulated results of the proposed antenna are well-matched in terms of gain, reflection coefficient (S11) and radiation patterns. The Proposed antenna is easy to implement, low cost, low profile and can be used in wireless services like Wi-Fi, Wi-MAX and C band applications. [ABSTRACT FROM AUTHOR]

This article presents a synthesis modelling of isolation in a diamond-shaped fractal electromagnetic band gag (DSFEBG) based two-port multiple input and multiple-output (MIMO) antenna using the Gaussian Process Regression (GPR). A compact two-port MIMO antenna with 0.140λ inter-element spacing is considered for isolation improvement. To predict mutual coupling in two-port MIMO antenna supervised learning-based regression technique of GPR, the model is trained with 50 samples and tested on 125 samples. The model performs result prediction in less than 1 second with RMSE less than 0.0001%. For a better understanding of the isolation between elements of the MIMO antenna, the automatic relevance determination property of GPR is presented. The proposed model does faster computation and is efficient in predicting isolation in DSFEBG based antennas for lower and high-frequency bands of 5G communication system. [ABSTRACT FROM AUTHOR]

A slit-loaded truncated-corner suspended rectangular patch antenna is analyzed using the equivalent circuit approach. The proposed antenna shows wideband behavior with dual circular polarization. The antenna provides an impedance bandwidth of 38.80% in the frequency range of 4.47–6.62 GHz. The 3-dB axial ratio bandwidths are 5.18% in the frequency range of 4.89–5.15 GHz and 2.45% in the frequency range of 6.43–6.59 GHz. The theoretical results are validated by method of moments (MoM)-based IE3D simulations and experimental results, revealing good agreement among the theoretical, simulated, and measured results. [ABSTRACT FROM AUTHOR]

In this paper, a high gain wideband circularly polarized (CP) microstrip antenna is presented for broadband operation. The proposed structure comprised of a partially grounded printed monopole antenna loaded with a split ring resonator and a metallic reflector. By using the metallic reflector surface underneath the patch radiator results in the reflected waves in the same phase with main lobe radiation, thereby improving the gain and it also acts like a secondary radiator to generate wideband CP behavior in the proposed design. A gain enhancement of 4.3 dBi is achieved in the operating frequency band as compared with the design without a metallic reflector. The maximum gain achieved in the presented method is 8.6 dBic over the entire operating range. The proposed design shows a wideband behavior ranging from 4.30 to 9.10 GHz with the 10-dB impedance bandwidth of 71.64%. In addition, the proposed design yielded a broadside right hand CP radiation with a 3-dB axial ratio bandwidth of 33.88% from 4.98 to 7.01 GHz. The proposed antenna is fabricated and experimental results on reflection coefficient, gain, axial ratio, and radiation patterns concede well with simulation results. [ABSTRACT FROM AUTHOR]

This article presents a compact size and high isolation 2 × 2, Multi-Input Multi-Output (MIMO) antenna for Industrial Scientific and Medical (ISM) band and 5G lower frequency band of 5G applications. Mutual coupling has been a great challenge in these applications. To improve isolation between elements of 2 × 2 MIMO antennas, a mushroom-shaped electromagnetic bandgap (EBG) and a fractal shaped EBG have been investigated. The overall size of the proposed antenna is 38.2 × 95.94 × 1.6mm³ with inter-element spacing (edge to edge) of 0.140λ. The proposed antenna has been designed, simulated, fabricated, and tested. The resulting outcome shows that the antenna operates in the band of 2.43-2.50 GHz and radiates in TM10 mode. By using fractal shaped EBG, isolation of -24.67 dB is achieved. Apart from isolation, other performance parameters of the MIMO antenna are verified. The proposed antenna is suitable for weather radar, surface ship radar, satellite communication, and wireless local area network (WLAN) applications. [ABSTRACT FROM AUTHOR]

New designs of the circularly polarized micro-strip antennas (CPMSAs) based on tree fractal geometries are proposed, examined experimentally, and compared. The excellent circularly polarized (CP) radiation with minimum axial ratio (AR) of 0.26 dB is achieved by optimization of the key parameters (angle, length, and width) of the fractal trees etched on the ground plane. Parametric study revealed that the fractal tree defected ground structures (FTDGS) are responsible for satisfying the condition of CP operation. The micro-strip antennas with third iterative FTDGS and modified third iterative FTDGS are fabricated on FR4 substrate. The measured 10-dB return loss and 3-dB AR are 99 MHz (2.407–2.506 GHz) and 12 MHz (2.443–2.455 GHz), respectively, with stable gain of 4.52 dBic at 2.45 GHz, for third iterative FTDGS antenna. For modified third iterative FTDGS antenna, measured 10-dB return loss and 3-dB AR are 109 MHz (2.354–2.463 GHz) and 26 MHz (2.386–2.412 GHz), respectively, with gain about 4.62 dBic in the vicinity of center frequency 2.4 GHz. The proposed designs can be good candidates for the unlicensed 2.45 GHz industrial, scientific, and medical (ISM) band applications. [ABSTRACT FROM AUTHOR]

This paper presents a circularly polarized wideband magnetoelectric dipole antenna with a defective semicircular patch for C-band applications (4–8 GHz). In the proposed design, in order to get proper impedance matching and stable gain, a pair of folded vertical patches is shorted between a pair of defective semicircular patches and minimum ground plane. The defective semicircular patches work as an electric dipole, while the vertical patches work as a magnetic dipole. The Γ-shaped single-feed structure is used to excite both dipoles together to achieve symmetrical radiation patterns. Minimum ground and the folded structure maintain the low profile of the presented design. The circular polarization is obtained by incorporating I-shaped slots in semicircular patches, extending to the lower and upper sides of the curved edges symmetrically on the both sides. A prototype was manufactured and the measured results agreed well with the simulated results. The results show an impedance bandwidth of 60.37% (S11 < − 10 dB) from 3.71 to 6.91 GHz, 3-dB axial ratio bandwidth of 20.60% from 3.71 to 4.55 GHz and a broadside stable gain of 6 ± 0.5 dBic. The antenna also shows good radiation efficiency of around 80% over the entire operating range. Therefore, the proposed antenna can be used in 5G Wi-Fi (5.15–5.875 GHz) wireless communication systems and several C-band applications. [ABSTRACT FROM AUTHOR]

This paper approaches a novel design theory of Low noise amplifier using reconfigurable rectangular shaped slotted patch antenna for 10.3-14 GHz receiver applications. In this approach, a Berkeley short-channel4 metal oxide field effect transistor (BSIM4, MOSFET) device is loaded in rectangular slotted patch antenna which results in wide band frequency of operation. To understand the design and analysis of low noise amplifier, an equivalent circuit model is extracted from the rectangular slotted patch antenna using finite element method (FEM) simulator where the slotted effect is considered. An extraction of equivalent model from the slotted patch antenna results in the L-C circuit which is used to perform an impedance transformation for low noise amplifier. A 12 GHz low noise amplifier using L-C circuit can improve performance parameters as per designer's requirement. A reconfigurable MOS loaded slotted patch antenna is verified using momentum microwave simulator and a wide bandwidth of 9 GHz in the frequency range of 10.3-19.3 GHz is achieved. The Low noise amplifier is simulated with TSMC 0.09 µm mixed signal/RF CMOS process technology. The post-layout circuit simulation results show that the proposed common source LNA with L-C network achieves a maximum power gain of 20 dB with the −3 dB bandwidth from the range of 10.3-13.6 GHz. A reflection coefficient of −14 dB and minimum noise figure of 1.6 dB is achieved. The power dissipation is 2.5 mW at 1.2 V supply voltage. [ABSTRACT FROM AUTHOR]

A novel triple-band microstrip fed planar monopole antenna is proposed and investigated. A fractal antenna is created by iterating a narrow pulse (NP) generator model at upper side of modified ground plane, which has a rhombic patch, for enhancing the bandwidth and gain. Three iterations are carried out to study the effects of fractal geometry on the antenna performance. The proposed antenna can operate over three frequency ranges viz, 3.34-4.8 GHz, 5.5-10.6 GHz and 13-14.96 GHz suitable for WLAN 5.2/5.8 GHz, WiMAX 3.5/5.5 GHz and X band applications respectively. Simulated and measured results are in good agreements with each others. Results show that antenna provides wide/ultra wide bandwidths, monopole like radiation patterns and very high antenna gains over the operating frequency bands. [ABSTRACT FROM AUTHOR]

The design and measurement of reconfigurable circularly polarized capacitive fed microstrip antenna are presented. Small isosceles right angle triangular sections are removed from diagonally opposite corners for the generation of circular polarization (CP) of axial ratio bandwidth of 11.1%. Horizontal slits of different lengths are inserted at the edges of the truncated patch to provide the dual-band CP and by switching PIN diodes across the slits ON and OFF, reconfigurable circularly polarized antenna is realized. The antenna shows dual-band behavior with reconfigurable CP. In order to enhance the operation bandwidth of the antenna, an inclined slot was embedded on the patch along with PIN diodes across the horizontal slits. This proposed antenna gave an impedance bandwidth of 66.61% (ON state) ranging from 4.42 to 8.80 GHz and 68.42% (OFF state) ranging from 4.12 to 8.91 GHz and exhibits dual-frequency CP with PIN diode in OFF state and single-frequency CP with PIN diode in ON state with good axial ratio bandwidth. The axial ratio bandwidth of 4.42, 2.35, and 2.72% is obtained from the antenna. The antenna has a similar radiation pattern in all the three different CP bands and almost constant gain within the bands of CP operation. [ABSTRACT FROM PUBLISHER]

In this paper, a reconfigurable stacked CMOS power amplifier using matched microstrip slant line for Ku-band application is proposed. This work is mainly focused on a matching component which is microstrip line and it is slanted at 45°. This component is applied in stacked power amplifiers which provide a higher output power and enhanced power added efficiency (PAE), improved impedance matching and wide impedance bandwidth. Two, three and four stacked power amplifiers with matched microstrip slant lines are designed, analyzed and compared. First demonstration uses a single microstrip slant line that covers a frequency range of operation from 7 to 15.9 GHz with impedance bandwidth of 8.9 GHz. This impedance bandwidth can be enhanced using proposed two or more stacks of microstrip slant lines and exhibits greater than 20 GHz impedance bandwidth with reconfigure band of operation. Two, three and four stacked power amplifiers are designed and simulated in the advanced design system using 45 nm predictive technology model process. As per the results of PAs, effective four stacked power amplifier design achieves maximum PAE of 57 % while a saturated output power of 20 dBm. The forward gain of 17.5 dB is obtained within frequency range of 11-17 GHz. [ABSTRACT FROM AUTHOR]

A new design of a circularly polarized planar magneto-electric dipole antenna is proposed and presented. This antenna consists of dual horizontal T-shaped electric dipole and an inverted Ushaped feed line. The antenna possesses 21.1% impedance bandwidth, from 8.9 GHz-11.0GHz, provides 3-dB axial ratio bandwidth of 9.52% ranging 10.0GHz-11.0GHz, exhibits stable omnidirectional radiation pattern with almost equal E-plane and H-plane radiation patterns and provides a peak gain of 6.2 dBi. Due to its good electrical characteristics and radiation parameters, the antenna is suitable for satellite and RADAR communication in X-band. [ABSTRACT FROM AUTHOR]

This paper focuses on a compact frequency switchable antenna for ultra wide band applications. The proposed antenna design consists of a rectangular monopole antenna with asymmetric cross slot and similar slot as a conductor on reverse plane, which achieves a wide band of 6.5-14.7 GHz with 77.3 % of fractional bandwidth. Additional resonances are excited and much wider impedance bandwidth is produced, especially at higher band by cutting an asymmetric cross slot on patch and a same slot as a conductor on the ground plane. Moreover, a RF p-i-n diode is diagonally positioned in an asymmetric cross slot on patch that achieves a feature of frequency re-configurability. A compactness of 67.3 % is achieved as compared to the normal re-configurable patch antenna. Simulated and measured results are used to demonstrate the performances of the antenna. The proposed design technique significantly enhances the system capability to operate with multiple operating frequencies. [ABSTRACT FROM AUTHOR]

The proposed work presents a co-design approach for a new asymmetric rectangular cross shaped slotted patch antenna with low noise amplifier that occupies 17.2-25.8 GHz wide-band for SDR applications. This co-design approach minimizes the chip area and noise and also improves integration system over the bandwidth of 8.6 GHz. Three different architectures have been designed in this work. Firstly, a two stage CMOS CG-CS LNA is designed using a technique of series-parallel resonant network as an input matching network and as inter-stage matching network between CG and CS LNA. In second architecture stage, a rectangular shaped microstrip antenna is designed and a slot of asymmetric cross shape is cut on the patch antenna. In third architecture the slotted antenna is integrated with low noise amplifier in order to form a co-design approach in which series-parallel resonant network is used as a band pass filter between slotted patch antenna and LNA. A two-stage CMOS LNA design is simulated and layout is made using foundry design kit for the TSMC 65 nm CMOS process in ADS.v.12. A simulation result of LNA achieves S of −21.4 dB with gain ranging from 7.4 to 21.3 dB over the wide-band of 19.1-28.8 GHz. The slotted antenna achieves S of −19 dB at 26 GHz and covers frequency range of 20.1-27.8 GHz with good radiation and receiving patterns. This co-design approach is analysed considering the 50 Ω impedance matching throughout the design and simulated on the platform of ADS.v.12. The best achievement of proposed co-design approach is reduced noise figure which is most suitable for SDR applications. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel quad-band circularly polarized capacitive coupled stacked patch antenna with wideband characteristics is presented for C-band applications (4-8GHz). In the proposed design, only two truncated patches with horizontal slits and inclined slot are stacked together to generate quad-band circular polarization operation and broadband behavior. The proposed antenna has achieved a bandwidth of 55.46% in the frequency band of 4.97-8.49 GHz and the 3-dB axial ratio bandwidths of 0.98%, 4.275%, 0.8869%, and 1.35% in four distinct bands of 5.1223-5.1729 GHz, 5.4710-5.7100 GHz, 6.2747-6.3306 GHz, and 7.6775-7.7822 GHz, respectively. The measured results show the good agreement with simulated results of the presented antenna and confirm the validity of design. The proposed antenna is useful for various C-band applications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2622-2628, 2015 [ABSTRACT FROM AUTHOR]

A full integration of single chip receiver system is remains to be a challenge in the area of millimetre wave (MMW) applications. In this paper, the integration of antenna, filter and CMOS low noise amplifier (LNA) is proposed which provides a new tri-design receiver system for MMW communication networks. A three-stage CMOS LNA is designed and integrated with co-design of filter and rectangular microstrip antenna which relaxes 50 Ω impedance matching constraint for designing at 40 GHz. Moreover, the new tri-design technique heavily improves the overall system integration, minimizes the noise and reduces the chip area and thus saving overall cost of the system. A three-stage CMOS LNA design is simulated and layouted using 90 nm CMOS design kit in ADS.v.12. The simulation result of CMOS LNA shows an achievement of 3.8 dB noise figure, 15.8 dB gain and −28 dB of return loss using proper impedance matching network. In addition, a theoretical analysis of three-stage CMOS LNA without using input-output matching network is done for the optimization of noise figure. A co-design of filter and patch antenna is also analyzed and integrated with CMOS LNA circuit. Finally, tri-design of receiver system demonstrates a peak gain of 25 dB and noise figure of 2.8 dB using proposed method. [ABSTRACT FROM AUTHOR]

In this paper a novel antenna with frequency notch characteristic has been presented. The antenna consists of a C-shaped microstrip antenna with two symmetrical notches and a rectangular parasitic patch. The antenna has tunable property due to integrated pin diode. When pin diode is OFF the antenna works like an ultra wide band antenna from 5 to 8 GHz. But when diode is ON the antenna has two bands separated by a small band-frequency notch. The antenna has very high cross polarization attenuation. The whole antenna is simulated on MoM based full wave electromagnetic simulator IE3D and fabricated. The results are in close resemblance. [ABSTRACT FROM AUTHOR]

In this paper, the design of compact, wideband and tunable antenna is presented. The proposed antenna is consisting of a U-slot, stacked, shorted rectangular patch and complementary split ring resonator on ground plane. The antenna utilizes the shorted wall, stacked structure and complementary split ring resonator for size reduction and wideband characteristics. The antenna tuning is realized by using PIN diode. By making PIN diode ON and OFF, antenna may be configured to wideband or dual band mode. Both the simulated and experimental results are presented. The proposed antenna provides a good radiation pattern and a relatively constant gain over entire band of frequency. The proposed antenna achieves a 15.38 % size reduction with wideband characteristics. [ABSTRACT FROM AUTHOR]

In this paper, a multiband circularly polarized capacitive coupled stacked microstrip antenna is proposed. The multiband circular polarization (CP) is achieved by corner truncation, embedding slits and inclined slots on a three layered antenna structure. The proposed antenna also shows wideband behavior with an impedance bandwidth of 52.13% in the frequency range of 4.85GHz to 8.27 GHz, while 3 dB axial ratio bandwidths in five CP bands are 0.51%, 4.54%, 0.33%, 0.83% and 1.29% in the frequency range of 5.12GHz to 5.15 GHz, 5.45 GHz to 5.70GHz, 5.90GHz to 5.92 GHz, 6.25 GHz to 6.31GHz and 7.68GHz to 7.78 GHz, respectively. The antenna prototype is fabricated, and simulated results as axial ratio, radiation pattern and the reflection coefficient are validated with measured result. [ABSTRACT FROM AUTHOR]

A novel compact triple band slit cut circular patch antenna with superstrate is proposed; slits on the patch provide additional resonances. The superstrate (cover) of dielectric layer provides protection to printed circuit antenna from environmental hazards due to abnormal weather conditions. The slits add two resonances in the resonance of a circular patch to achieve triple band antenna for multi services. The dielectric superstrate or cover above the microstrip patch causes the change in fringing fields between the patch and ground plane. The change in fringing field is accounted to calculate the effective relative permittivity. The effective permittivity is considered to evaluate the changes in resonance frequency due to superstrate. The various parameters of the antenna have been investigated and the antenna is simulated on Ansoft's HFSS software simulator. A prototype of antenna is fabricated to confirm the return loss by measurement using the Agilent Technologies' N5230A PNA-L Network Analyzer. The proposed structure with superstrate possess triple band characteristics and provides protection from environmental hazards. The resonating frequencies of the bands are 7.3, 8.7 and 10.3 GHz. The analytical results are found in good agreement with the simulated results obtained by Ansoft's HFSS and further confirmed by measurement. Antenna is worth for X band operations such as remote sensing, WPAN and military satellite communication and vehicular applications. [ABSTRACT FROM AUTHOR]

In this paper a novel structure of annular ring loaded stacked circular patch microstrip antenna is theoretically analysed to observe various parameters such as return loss, input impedance, gain, directivity and radiation pattern. It is found that antenna possess three band of operation which signify the compactness and multiband operation of antenna. The antenna is resonating at three operating frequencies 1.720, 2.950, 3.060 GHz. The proposed theory is verified by simulation using Ansoft's HFSS and theoretical results are in good agreement with simulated results. The antenna is useful for multi-services operations such as WLAN, GSM, UMTS, and WiMAX services. [ABSTRACT FROM AUTHOR]

A tunable L-strip fed circular microstrip antenna on thick substrate with CSRR in the ground plane has been analysed and investigated. The antenna is analysed using cavity model and circuit theoretic approach for initial design and then simulated on IE3D simulation software. The antenna is made tunable with PIN diode which makes it to work in different configurations. Two diodes were used to implement a double annular slot, one annular slot and one split slot and CSRR in the ground plane. While other configurations of diodes provide bandwidth and radiation pattern diversity, CSRR provides size reduction of upto 13.31 % along with high gain directivity and radiation efficiency. A maximum gain of 8 dBi, directivity 8.3 dBi has been achieved in the respective band of operations. The antenna exhibits wideband along with multiband characteristic. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents design and analysis of a novel compact circular patch microstrip antenna to be used for multiple services. The study is done on a circular patch antenna loaded with four slits which has a meandering effect on the surface currents along with a single unit cell of a split ring resonator (SRR) printed with copper on a substrate for the multiband operations. Circuit model of SRR configuration is also presented. The proposed antenna configuration is simulated and theoretically analyzed. The antenna is fabricated for best performance. The theoretical and simulated results are found to be in close agreement with measured results. Furthermore, parametric analysis is done by varying the height of SRR and gap width between the two SRR rings. Proposed configuration with a compactness of around 28%, and a broad beam width with high-efficiency cover X-band of microwave regime between 6 and 12 GHz. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2787-2795, 2013 [ABSTRACT FROM AUTHOR]

A new frequency agile BST varactor loaded stacked circular microstrip antenna is presented. The antenna is analysed using extended cavity model. One of two bands of antenna is tunable with the help of BST varactor. The upper band is useful for WiMAX and lower band for other wireless communication systems. Various antenna parameters like return loss, resonant frequency, frequency agility etc. have been investigated. The simulated results agree well with the numerical data. A frequency agility of 60.64 % is achieved, which is better than simple Varactor diode loaded antenna. Lowest resonant frequency of 0.866 GHz is obtainable that shows a significant physical area reduction. The group delay of S $$_{11}$$ remains constant for entire band of operation. [ABSTRACT FROM AUTHOR]

A novel model of a wide frequency range double MOS loaded circular microstrip patch antenna with airgap between ground plane and substrate is proposed. In this structure two metal oxide semiconductor (MOS) devices are loaded on the patch to enhance the operating frequency range of antenna. To investigate the antenna, different parameters such as resonance frequency, input impedance, frequency agility, VSWR, radiation pattern etc. are calculated and simulated. The resonant frequency of proposed 10 mm radius patch is upward shifted from 5.2 to 6.8 GHz using 1 mm airgap and by loading MOS, antenna can be tuned down to 1.27 GHz operating frequency, which leads to compactness and tunability of antenna. Proposed antenna can be tuned between 1.27 and 6.8 GHz frequency of operation which makes the antenna highly suitable for wide frequency range of mobile communication. The proposed double MOS loaded antenna possessed 82.94 % frequency agility. The antenna is worth for GPS, WLAN, UMTS, and WiMAX operations. [ABSTRACT FROM AUTHOR]

An analysis and design of a novel ultra wideband L-strip proximity coupled slot loaded circular microstrip antenna is proposed. The theoretical model is developed using circuit theoretic approach and obtained results are validated by MoM based IE3D simulation software. Theoretical results show a good agreement with simulated results. The patch is designed on a thick substrate of thickness 11 mm for a design frequency of 3.74 GHz and provides ultra wide band operation. The parametric study is carried out for return loss, radiation pattern, antenna efficiency, radiation efficiency and gain. It is observed that the bandwidth of the antenna depends on slot parameter and L-strip feed dimensions. An ultra bandwidth of 2.82 GHz is achieved with consistent radiation characteristics. [ABSTRACT FROM AUTHOR]

An L-strip proximity coupled circular microstrip antenna is proposed. The structure is investigated using circuit theoretic approach and simulated using IE3D simulation software. The patch is designed on a thick substrate of thickness of 11 mm for a design frequency of 3.74 GHz and provides ultra wide band operation. The numerical results for input impedance, VSWR, radiation pattern, efficiency and gain are presented. Bandwidth is found to be dependent on length of horizontal part of L-strip. A bandwidth of 69.52% is achieved (for VSWR≤2) for y0=0.112λ0 and h2=0.097λ0. The beam of antenna rotates with operating frequency. [ABSTRACT FROM AUTHOR]