Multi Band Research Articles

Using multiband multi-echo imaging to improve the robustness and repeatability of co-activation pattern analysis for dynamic functional connectivity

Emerging evidence has shown that functional connectivity is dynamic and changes over the course of a scan. Furthermore, connectivity patterns can arise from short periods of co-activation on the order of seconds. Recently, a dynamic co-activation patterns (CAPs) analysis was introduced to examine the co-activation of voxels resulting from individual timepoints. The goal of this study was to apply CAPs analysis on resting state fMRI data collected using an advanced multiband multi-echo (MBME) sequence, in comparison with a multiband (MB) sequence with a single echo. Data from 28 healthy control subjects were examined. Subjects underwent two resting state scans, one MBME and one MB, and 19 subjects returned within two weeks for a repeat scan session. Data preprocessing included advanced denoising namely multi-echo independent component analysis (ME-ICA) for the MBME data and an ICA-based strategy for Automatic Removal of Motion Artifacts (ICA-AROMA) for the MB data. The CAPs analysis was conducted using the newly published TbCAPs toolbox. CAPs were extracted using both seed-based and seed-free approaches. Timepoints were clustered using k-means clustering. The following metrics were compared between MBME and MB datasets: mean activation in each CAP, the spatial correlation and mean squared error (MSE) between each timepoint and the centroid CAP it was assigned to, within-dataset variance across timepoints assigned to the same CAP, and the between-session spatial correlation of each CAP. Co-activation was heightened for MBME data for the majority of CAPs. Spatial correlation and MSE between each timepoint and its assigned centroid CAP were higher and lower respectively for MBME data. The within-dataset variance was also lower for MBME data. Finally, the between-session spatial correlation was higher for MBME data. Overall, our findings suggest that the advanced MBME sequence is a promising avenue for the measurement of dynamic co-activation patterns by increasing the robustness and reproducibility of the CAPs.

Development of microwave metamaterial-inspired sensors with multiple-band reactivity for mercury contamination detection

Alternative contactless metamaterial-inspired microwave sensors, composed of a multi-band omnidirectional bowtie antenna and metamaterials, are developed to detect and identify mercury, one of the most widespread toxic heavy metals, in the C-band and S-band, using reflection coefficients. A multi-negative refractive index band metamaterial is specifically designed as a sensing enhancer, where the multi bands can effectively trigger the electromagnetic properties, as well as enhance the differentiation between the mercury samples. The geometry of the metamaterial and its arrangement and orientation are optimized to reach the system highest sensitivity. The proposed sensors were tested on mercury traces of various volumes and weights. Our study has shown that the electromagnetic responses of the mercury in the microwave range are nonlinear, yet predictable. Six distinguishable resonances generated while testing the samples specify the capability of identifying the mercury amount, which can effectively trace mercury contamination in water and seawater.

Wideband ring mixer for band #1 of MB-OFDM systems in 180 nm CMOS technology

Abstract A wideband down conversion ring mixer is proposed for multi band orthogonal frequency division multiplexing (MB-OFDM) system in 180 nm CMOS technology. The mixer is essentially used in a heterodyne wireless receiver to enhance the selectivity of the system. Being a nonlinear system, the mixer dominates the overall performance of the system. The design of down conversion mixer is the most challenging part of a receive chain. Wideband impedance matching always remains a challenge in any radio frequency integrated circuit design. This paper presents the design of a ring mixer with high linearity, wideband impedance matching using differential resistive impedance matching and without using any DC bias. The proposed mixer is tuned for a frequency of 3.432 GHz of band 1 of the MB-OFDM system. Mixer core is based on the FET ring mixer topology. The mixer is implemented in 180 nm CMOS technology. The mixer achieves the minimum conversion loss of 10.49 dB, 1 dB compression point (P1) of 12.40 dBm, third order input intercept point (IIP3) of 12.01 dBm, a minimum SSB noise figure of 8.99 dB, and S 11 of less than -10 dB over the frequency range of 0 to 13.61 GHz . The layout of the mixer records an active area of 183.75 μm 2 .

基于高动态范围成像的温室番茄植株图像色彩矫正方法

In this paper, aiming at the need of stable access to visual information of intelligent management of greenhouse tomatoes, the color correction method of tomato plant image based on high dynamic range imaging technology was studied, in order to overcome the objective limitation of complex natural lighting conditions on the stable color presentation of working objects. In view of the color distortion caused by the temporal and spatial fluctuation of illumination in greenhouse and sudden change of radiation intensity in complex background, a calibration method of camera radiation response model based on multi-exposure intensity images is proposed. The fusion effect of multi band image is evaluated by field test. The results show that after multi band image fusion processing, the brightness difference between the recognized target and other near color background is significantly enhanced, and the brightness fluctuation of the background is suppressed. The color correction method was verified by field experiments, and the gray information, discrete degree and clarity of tomato plant images in different scenes and periods were improved.

Power quality and transient analysis for a utility-tied interfaced distributed hybrid wind-hydro controls renewable energy generation system using generic and multiband power system stabilizers

Due to its inherent ability of augmenting power system stability limit while maintaining good electric Power Quality (PQ), Power System Stabilizer (PSS) is envisaged to be an effective device in numerous Distributed Generation (DG) applications. It becomes a paramount work to maintain stable frequency, and alleviate the utility-grid collapse. Owing to this, this paper evaluates the performance of generic, and Multiband (MB)-PSSs for a hybrid 9 MW wind farm connected with mini/micro hydro power plant. The proposed system is interfaced with 200 MVA, 25 kV utility-grid system. A comparative analysis in the performance of a generic-PSS is presented with a MB-PSS at various voltage level points and power flows at various Point of Common Couplings (PCC) are analysed. Transient analysis is carried out during the presence of various unsymmetrical faults. It is envisaged that transients and unbalanced voltage sag-swells are mitigated at various PCCs while maintaining uninterruptable real and reactive power flows. The superiority of MB-PSS is established over generic-PSS in maintaining optimal PQ flow. Consequently, the reactive power requirement of the connected load is compensated by wind and mini/micro hydro controlling schemes using MB-PSS. Overall, the accurateness of the developed simulink models is demonstrated and satisfactory results are obtained in comparative analysis of both stabilizers.

Retrieval of Suspended Sediment in Songhua River Based on Sentinel-2 Satellite

In view of the current situation that the remote sensing inversion of suspended sediment is mainly based on low spatial resolution satellite data, sentinel-2 satellite data with resolution of up to 10m is used to retrieve the suspended sediment content in Harbin section of Songhua River. And the inversion model is established based on the measured data and remote sensing data. The results show that the fitting degree of b3/(B2 + B4) in the multi band ratio and the measured suspended sediment concentration is the highest, reaching 0.904. The results show that the average relative error between the inversion value and the measured value is 19.88%, and the root mean square error is 0.039g/l. The results show that the suspended sediment content of Songhua River is lower than that of other six rivers in China, and belongs to the less sand river. The sediment content on both sides of the bank is higher than that of the center of the river. In the wide river, the suspended sediment content is low, and the suspended sediment content is higher in the narrow area.

Safety and data quality of EEG recorded simultaneously with multi-band fMRI.

Simultaneously recorded electroencephalography and functional magnetic resonance imaging (EEG-fMRI) is highly informative yet technically challenging. Until recently, there has been little information about EEG data quality and safety when used with newer multi-band (MB) fMRI sequences. Here, we measure the relative heating of a MB protocol compared with a standard single-band (SB) protocol considered to be safe. We also evaluated EEG quality recorded concurrently with the MB protocol on humans. We compared radiofrequency (RF)-related heating at multiple electrodes and magnetic field magnitude, B1+RMS, of a MB fMRI sequence with whole-brain coverage (TR = 440 ms, MB factor = 4) against a previously recommended, safe SB sequence using a phantom outfitted with a 64-channel EEG cap. Next, 9 human subjects underwent eyes-closed resting state EEG-fMRI using the MB sequence. Additionally, in three of the subjects resting state EEG was recorded also during the SB sequence and in an fMRI-free condition to directly compare EEG data quality across scanning conditions. EEG data quality was assessed by the ability to remove gradient and cardioballistic artifacts along with a clean spectrogram. The heating induced by the MB sequence was lower than that of the SB sequence by a factor of 0.73 ± 0.38. This is consistent with an expected heating ratio of 0.64, calculated from the square of the ratio of B1+RMS values of the sequences. In the resting state EEG data, gradient and cardioballistic artifacts were successfully removed using traditional template subtraction. All subjects showed an individual alpha peak in the spectrogram with a posterior topography characteristic of eyes-closed EEG. The success of artifact rejection for the MB sequence was comparable to that in traditional SB sequences. Our study shows that B1+RMS is a useful indication of the relative heating of fMRI protocols. This observation indicates that simultaneous EEG-fMRI recordings using this MB sequence can be safe in terms of RF-related heating, and that EEG data recorded using this sequence is of acceptable quality after traditional artifact removal techniques.

Analysis of substrate materials for millimeter wave antenna applications

A compact and novel multi band series fed array antenna is simulated and analyzed for antenna applications in millimeter-wave frequency ranges. The single element antenna performance is investigated for different flexible substrate materials like Rogers Ultralam, Arlon Diclad 880, Neltec NY9220, Taconic TLY, Polyethylene and Polystyrene in initial stages. The proposed series fed array antenna operates (S11<-10dB) in 14.7-20.8GHz, 23.125.8GHz, 28.5-34.8GHz and 39.3-44.8GHz frequency bands. The designed antenna exhibits negative group delay characteristics from 18.2-19.9GHz, 29.9-33.3GHz, 39.4-42GHz and 42.6-43.6GHz. It achieved a peak gain of 13.9dB at 42.5GHz and radiation efficiency of 97.5% at 33GHz. Results obtained are in fine conformity and therefore, proposed antenna is preferable for mmwave applications.

Dual-Band Frequency Absorber Based on Split-Ring Resonators for WiMAX and WLAN Bands

In this paper, a dual-band compact absorber design based on split-ring resonator for WiMAX and WLAN bands is presented. Top plate of a unit cell in the proposed design is composed of three concentric circular split ring (SR) elements covers an area of π×13.42 mm2 and placed on a FR4 substrate with 1.5 mm thickness, dielectric constant of 4.3 and loss tangent of 0.025. Also, six miniature metallic loadings are appropriately inserted between the SR elements. The back side of the substrate is covered full ground plane for shielding transmission from port 1 to port 2. In the design, SR elements are primary resonator of the proposed absorber and provide a dual band of absorption at the respective frequencies. The metallic loadings are used for fine frequency tuning where the absorption peaks occur. Hence, the absorption frequency of the design can be easily tuned by means of sliding the loadings between the rings without changing any design parameters. The proposed compact absorber excited by incident electromagnetic wave provides 0.92 and 0.97 absorption peaks at 3.52 GHz WiMAX and 5.16 GHz WLAN bands, respectively. The design and analysis of the absorber are performed by means of CST Microwave Studio based on frequency domain solver. In this paper, the absorber design with novel configuration is introduced in detail and its corresponding electric field distributions and absorption characteristics at the related bands are presented. Also, the proposed SRR-based absorber design is compared with the previously reported dual or multi bands absorbers in terms of dimensions, resonance frequencies and number of bands.

MESMERISED: Super-accelerating T1 relaxometry and diffusion MRI with STEAM at 7 T for quantitative multi-contrast and diffusion imaging

There is an increasing interest in quantitative imaging of T1, T2 and diffusion contrast in the brain due to greater robustness against bias fields and artifacts, as well as better biophysical interpretability in terms of microstructure. However, acquisition time constraints are a challenge, particularly when multiple quantitative contrasts are desired and when extensive sampling of diffusion directions, high b-values or long diffusion times are needed for multi-compartment microstructure modeling. Although ultra-high fields of 7 T and above have desirable properties for many MR modalities, the shortening T2 and the high specific absorption rate (SAR) of inversion and refocusing pulses bring great challenges to quantitative T1, T2 and diffusion imaging. Here, we present the MESMERISED sequence (Multiplexed Echo Shifted Multiband Excited and Recalled Imaging of STEAM Encoded Diffusion). MESMERISED removes the dead time in Stimulated Echo Acquisition Mode (STEAM) imaging by an echo-shifting mechanism. The echo-shift (ES) factor is independent of multiband (MB) acceleration and allows for very high multiplicative (ESxMB) acceleration factors, particularly under moderate and long mixing times. This results in super-acceleration and high time efficiency at 7 T for quantitative T1 and diffusion imaging, while also retaining the capacity to perform quantitative T2 and B1 mapping. We demonstrate the super-acceleration of MESMERISED for whole-brain T1 relaxometry with total acceleration factors up to 36 at 1.8 mm isotropic resolution, and up to 54 at 1.25 mm resolution qT1 imaging, corresponding to a 6x and 9x speedup, respectively, compared to MB-only accelerated acquisitions. We then demonstrate highly efficient diffusion MRI with high b-values and long diffusion times in two separate cases. First, we show that super-accelerated multi-shell diffusion acquisitions with 370 whole-brain diffusion volumes over 8 b-value shells up to b = 7000 s/mm2 can be generated at 2 mm isotropic in under 8 minutes, a data rate of almost a volume per second, or at 1.8 mm isotropic in under 11 minutes, achieving up to 3.4x speedup compared to MB-only. A comparison of b = 7000 s/mm2 MESMERISED against standard MB pulsed gradient spin echo (PGSE) diffusion imaging shows 70% higher SNR efficiency and greater effectiveness in supporting complex diffusion signal modeling. Second, we demonstrate time-efficient sampling of different diffusion times with 1.8 mm isotropic diffusion data acquired at four diffusion times up to 290 ms, which supports both Diffusion Tensor Imaging (DTI) and Diffusion Kurtosis Imaging (DKI) at each diffusion time. Finally, we demonstrate how adding quantitative T2 and B1+ mapping to super-accelerated qT1 and diffusion imaging enables efficient quantitative multi-contrast mapping with the same MESMERISED sequence and the same readout train. MESMERISED extends possibilities to efficiently probe T1, T2 and diffusion contrast for multi-component modeling of tissue microstructure.

Ku/Ka band diplexer based on thin-film technology for small ground-segment user terminals

AbstractThis paper describes the outcome of the “Small user TErminal multi band DIplexer” project where the goal is the validation of novel SMD-compliant planar diplexer. The real application scenario concerns an integrated multi-band radio terminal for ground-segment satellite links. The advantageous and novel approach involves the simultaneous use of three different well-established concepts: a microstrip low-pass filter, a substrate integrated waveguide high-pass filter, and the thin-film technology as manufacturing process. The proposed topology applied to a planar alumina-based design guarantees a 15 × 11.1 mm2 footprint and the best integration with surface mountable soldering process over standard PCB technology. Achieved performance and resilience to environmental toughness are suitable for consumer-oriented satellite links or man-pack applications. The designed component targets the Ku 10.7–12.75 (RX) and Ka 27.5–30 (TX) GHz bands but the layout can be easily tuned across the spectrum. The described solution has been manufactured and validated. Thermal cycling and mechanical tests have been carried out to prove the high technology readiness level of the proposed device.

Hard magnet topological semimetals in XPt3 compounds with the harmony of Berry curvature

Topological magnetic semimetals, like Co3Sn2S2 and Co2MnGa, display exotic transport properties, such as large intrinsic anomalous (AHE) due to uncompensated Berry curvature. The highly symmetric XPt3 compounds exhibit anti-crossing gapped nodal lines, a driving mechanism in the intrinsic Berry curvature Hall effects. Uniquely, these compounds contain two sets of gapped nodal lines that harmoniously dominate the Berry curvature in this complex multi band system. We calculate a maximum AHE of 1965 S cm-1 in the CrPt3 by first principles electronic structure. We have grown high-quality CrPt3 thin films with perpendicular magnetic anisotropy by magnetron sputtering and measured a robust AHE of 1750 S cm−1 for different sputtering growth conditions. Additionally, the cubic films display an easy magnetic axis along [111] direction. The facile and scalable fabrication of these materials is prime candidates for integration into topological devices.

Design and Simulation of Extended Interaction Cavities for a Ka band Multi beam Klystron

This article reports about the design approach, electromagnetic simulation and analysis results of high-frequency ladder-type input, output, and intermediate RF cavaties for Ka-band multi-beam extended interaction klystron. Several parameters of the cavity, such as quality factor, shunt impedance, etc., have been investigated by the assistance of electromagnetic software CST microwave studio.

Electron transport in dual-gated three-layer MoS2

The low-energy band structure of few-layer MoS$_2$ is relevant for a large variety of experiments ranging from optics to electronic transport. Its characterization remains challenging due to complex multi band behavior. We investigate the conduction band of dual-gated three-layer MoS$_2$ by means of magnetotransport experiments. The total carrier density is tuned by voltages applied between MoS$_2$ and both top and bottom gate electrodes. For asymmetrically biased top and bottom gates, electrons accumulate in the layer closest to the positively biased electrode. In this way, the three-layer MoS$_2$ can be tuned to behave electronically like a monolayer. In contrast, applying a positive voltage on both gates leads to the occupation of all three layers. Our analysis of the Shubnikov--de Haas oscillations originating from different bands lets us attribute the corresponding carrier densities in the top and bottom layers. We find a twofold Landau level degeneracy for each band, suggesting that the minima of the conduction band lie at the $\pm K$ points of the first Brillouin zone. This is in contrast to band structure calculations for zero layer asymmetry, which report minima at the $Q$ points. Even though the interlayer tunnel coupling seems to leave the low-energy conduction band unaffected, we observe scattering of electrons between the outermost layers for zero layer asymmetry. The middle layer remains decoupled due to the spin-valley symmetry, which is inverted for neighboring layers. When the bands of the outermost layers are energetically in resonance, interlayer scattering takes place, leading to an enhanced resistance and to magneto-interband oscillations.

A miniaturized 2-itertion rectangular slotted Sierpinski Fractal Bowtie antenna for multiband applications

Recent advancements in the field of Telecommunications and wireless technology services need compact, multiband antennas with reduced system complexity. In this paper a novel Rectangular slotted Sierpinski Fractal Bowtie antenna is illustrated and is further expanded up to 2-iterations to obtain multi frequency bands with increased percentage of Miniaturization. The overall volume of the proposed 2-iteration SPK Bowtie antenna is (50 × 50 × 1.6) mm3 and the substrate is FR-4 epoxy with 4.4 dielectric constant. All the 0th, 1st and 2nd iterations of Rectangular slotted SPK Fractal Bowtie antenna are exited with coaxial probe feed and are simulated using ANSYS HFSS software for 100 MHz to 14 GHz frequency range. The radiation parameters like return loss, Bandwidth, VSWR, and Gain are evaluated and compared. The simulation results shows that proposed 2nd iteration Rectangular slotted SPK Fractal Bowtie antenna exhibits more number of frequency bands as compared to the 0th and 1st iterations. The proposed design is able to resonate at frequencies 0.2 GHz, 3.5 GHz, 6.3 GHz, 8.6 GHz, 10.9 GHz, 11.7 GHz with a gain of 0.529 dB, 5.074 dB, 4.518 dB, 5.335 dB, 9.18 dB, 21.17 dB respectively. The percentage of Miniaturization is also increased to 58.2% in the case of 2-iteraion. A prototype of the final proposed antenna is fabricated and tested using VNA network analyzer. The fabricated prototype of proposed antenna is also capable of resonating in L, C, S, and X bands. The simulated results of the proposed antenna have a great matching with the measured results.

Abnormal Seebeck effect in doped conducting polymers

The Seebeck effect or thermopower relates the temperature gradient to the electric voltage drop. Seebeck coefficient α measures the transport entropy, which could either linearly increase with temperature T like metallic conducting or decrease as 1/T like semiconducting behavior. It could become more complicated in the temperature dependence for a number of disordered systems but still in a monotonic way. However, several recent experiments reported the “abnormal” non-monotonic temperature dependence of the Seebeck coefficient in doped conducting polymers, for instance, first increasing and then decreasing. Through a one-dimensional tight-binding model coupled with the Boltzmann transport equation, we investigate theoretically the doping effect for the Seebeck coefficient. We find that the abnormal behavior comes from multi bands' contribution and a two-band model (conduction or valence band plus a narrow polaronic band) can address such an abnormal Seebeck effect, namely, if there exists (i) a small bandgap accessible for thermal activation between the two bands; and (ii) a large difference in the bandwidth between the polaronic band and the conduction band (or valence band), then the Seebeck coefficient increases with temperature first, then levels off, and finally drops down.

Which multiband factor should you choose for your resting-state fMRI study?

Multiband acquisition, also called simultaneous multislice, has become a popular technique in resting-state functional connectivity studies. Multiband (MB) acceleration leads to a higher temporal resolution but also leads to spatially heterogeneous noise amplification, suggesting the costs may be greater in areas such as the subcortex. We evaluate MB factors of 2, 3, 4, 6, 8, 9, and 12 with 2 mm isotropic voxels, and additionally 2 mm and 3.3 mm single-band acquisitions, on a 32-channel head coil. Noise amplification was greater in deeper brain regions, including subcortical regions. Correlations were attenuated by noise amplification, which resulted in spatially varying biases that were more severe at higher MB factors. Temporal filtering decreased spatial biases in correlations due to noise amplification, but also tended to decrease effect sizes. In seed-based correlation maps, left-right putamen connectivity and thalamo-motor connectivity were highest in the single-band 3.3 mm protocol. In correlation matrices, MB 4, 6, and 8 had a greater number of significant correlations than the other acquisitions (both with and without temporal filtering). We recommend single-band 3.3 mm for seed-based subcortical analyses, and MB 4 provides a reasonable balance for studies analyzing both seed-based correlation maps and connectivity matrices. In multiband studies including secondary analyses of large-scale datasets, we recommend reporting effect sizes or test statistics instead of correlations. If correlations are reported, temporal filtering (or another method for thermal noise removal) should be used. The Emory Multiband Dataset is available on OpenNeuro.

Proof-of-Concept of the Time and Spectral Optical Aggregation Network

In this article, we present the proof of concept (PoC) of the time and spectral optical aggregation (TISA) approach that allows a better filling of the time and spectral resources of an optical transport network. Some innovative solutions have been implemented, such as a new and fast tunable laser that permits to color the bursts sent in the TISA network, as well as their transmission with both DP-QPSK and DP-16QAM coherent multi-band (MB) OFDM formats. BER versus OSNR measurements have been achieved showing less than 1-dB penalty in back-to-back or after transmission. The tolerance of bursts against frequency mismatch occurring between the transceiver and the optical filter that extracts a sub-band inside the MB-OFDM signal has also been evaluated, and ∼1.5 GHz tolerance has been measured for bursts of ∼6.7 GHz bandwidth. Furthermore, in order to mitigate the transients in the coherent receiver that faces alternatively the presence or absence of signal, a novel channel estimator based on a sliding window has been introduced. Its efficiency and performance has been experimentally validated, and its ability to suppress the error threshold of the BER versus OSNR curves has been demonstrated. By the experimental proof of concept delivered here, the ability of the TISA network to perform with a good level of performance the transparent routing and sub-wavelength aggregation/disaggregation in the time and spectral domains simultaneously has been established. Beyond the important and crucial aspect of the optimal filling of the optical resources, our PoC demonstrate the ability of the TISA approach to push the flexibility of an optical transport network at its limit while allowing a cost and power consumption limitation obtained by the removal of costly and power-hungry optical-electrical-optical regenerators.

Highly Absorptive Chiral L-Shape MDM Plasmonic Metasurface as Multifunction Device: Design and Computational Studies

A multifunction plasmonic metasurface made of metal-dielectric-metal (MDM) layers is designed, and its chiral, absorption, and refractive index sensing properties are studied numerically using finite difference time domain (FDTD) computation. Top layer of the proposed novel metasurface consists of four L-shape gold strips arranged in a specific orientational sequence into a square unit cell whose period (along X direction and Y direction) is varied from 800 to 1400 nm in a step of 200 nm. The proposed super-structure shows highly chiral behaviour with multi bands circular dichroism (CD) between ~ 600 and 1200 nm with highest CD value of about 0.4. The CD spectral response is seen to be tunable with the structural parameters such as periods and appropriate L-strip length. True chiral nature of the proposed structure is cross-checked by computing its enantiomer that shows a mirror reflection of CD response of the original structure. Multi-work functionalities are investigated by studying perfect absorption and refractive index sensing properties of the metasurface. The study shows polarization independent multi-resonance spectral absorption that reaches to ~ 100% in some cases. On the other hand, refractive index sensing study shows high sensitivity (S) of 700–750 nm/RIU (per refractive index unit) with figure of merit (FOM) of 5–10. Owing to its exotic optical properties, the novel metasurface may be considered for chip level integration for multi-purpose work functionalities.

PERFORMANCE IMPROVED TRIANGULAR MULTI BAND ANTENNA USING REACTIVE IMPEDANCE SUBSTRATE AND FREQUENCY SELECTIVE SURFACE

In modern world, communication devices need to be operated for more than one frequency bands. Lot of research works were carried out in the field of multiband antennas. The one major concern in the design of multiband patch antenna are the gain and bandwidth. Both gain and bandwidth of the multi band antenna can be improved for the better performance. In this paper a triangular multiband antenna is designed and the gain of the antenna is enhanced by the blend of reactive impedance surface and Frequency selective surface. The proposed antenna resonates 3.4 GHz, 4.2 GHz, 6.75 GHz,7.1 GHz, 7.5 GHz and 9.3 GHz with a better return loss and gain.