Measurement shows the mutual coupling reduction of over 55 db. This book considers a cylindrical phased array with microstrip patch antenna elements and halfwavelength dipole antenna elements. Petkov explored the mutual coupling between microstrip antennas provoked by the surface wave 31. Wide scan phased array patch antenna with mutual coupling. It is due to excitation of surface wave, space wave and near field overlapping of the array elements. Mutual coupling in conformal microstrip patch antenna arrays. Results for 2 element patch array antenna using coaxial line feed without ebg. Reduction of the mutual coupling in patch antenna arrays based on ebg by using a planar frequencyselective surface structure volume 9 issue 2. The first proposed antenna array is producing bandwidth and mutual coupling equal to 66. The reduction in the gain of the inductively loaded patch array compared to the conventional array is the negative feedback through which the inductive currents cancel out 9.
If the energy received by all the antennas in your array are highly correlated, then you dont really have an antenna array. Mutual coupling degrades not just the antenna efficiency, but it can alter the antenna s radiation pattern as well. Mutual coupling degrades not just the antenna efficiency, but it can alter the antennas radiation pattern as well. Mutual coupling effect of microstrip antenna array sciencedirect. However, analysis of realistic arrays must also consider mutual coupling effect. Mutual coupling modeling and calibration in antenna arrays. Types of array elements in antenna toolbox array library. The antenna radiation characteristics are observed to be fairly consistent over the large operating bandwidth of 4. It leads to degradation in radiation pattern and reduction in gain. From the comparison, it can be seen that using the isolated patch element is a useful first step in understanding the effect that a realistic antenna element would have on the array pattern. The effect of platform and mutual coupling effect is included in the analysis. The proposed antenna is fabricated and there is an acceptable agreement between the simulated and measured results. Advantages over single antenna high gain increase in directivity. This coupling effect is also known to directly or indirectly influence the steady state and transient response.
A 10 db mutual coupling reduction is achieved at the resonant frequency10ghz, which proves that the surface wave is suppressed but the bandwidth decreases with 0. Index termsantenna arrays, broadband, focused array, microstrip antenna, mutual. For example, the plot shows the mutual impedance of a twoelement dipole array as a function of interelement spacing. The relative displacement d is fixed as lambda2, two patches placed sidebyside configuration and the patches positioned in the center of the rectangular 160mm x 100mm ground.
To verify and confirm the simulation results, a prototype of the cllmtm superstrate incorporating an array of rectangular patch antennas are fabricated and tested. The mutual coupling between antenna elements affects the antenna parameters like terminal impedances, reflection coefficients and hence the antenna array performance in terms of radiation characteristics, output signaltointerference noise ratio sinr, and radar cross section rcs. Any change in the interelement spacings changes the mutual impedance between the antenna elements. Based on the method of moments, the authors analyze the microwave structure on the microstrip antenna patch surface. Comparison of proposed dgs with other approaches for mutual coupling reduction in microstrip array. In this paper, the method is tested on patch antennas mounted on planar and cylindrical surfaces. It will affect the antenna array, mainly it changes the array radiation pattern, and matching characteristics of the antenna elements.
The array has a dolphtschebyscheff amplitude taper. The changes of mutual coupling are clearly shown after the ebg is inserted, the mutual coupling is increased to 41. The mutual coupling before the ebg is inserted between the patch is 30. A simple technique to reduce the mutual coupling between patch antenna arrays is proposed. For the examples considered, it is shown that the simulated results are. Pdf a simple technique to reduce the mutual coupling between patch antenna arrays is proposed. The effect of mutual coupling is serious if the element spacing is small. Pdf mutual coupling in antenna arrays researchgate. Active or scan impedance, array factor and pattern multiplication, coupling matrix, isolated or embedded element pattern. Analytical expressions for mutual coupling between the patch elements are derived and effect of the elemental spacing on the mutual coupling between the microstrip elements is presented. In this paper, the method is tested on patch antennas mounted on.
This work presents a summary of the mutual coupling reduction. Attari department of electrical engineering, ferdowsi university of mashhad, iran corresponding author. Tadjalli, journalieee antennas and wireless propagation letters, year2010, volume9. After loading the decoupling structures in the antenna array, the gain increased from 5. Sparameter responses of the proposed antenna array without and with the proposed mswi are shown in fig. In the first configuration, one ml is inserted in the slot of the ground and a. Mutual coupling phenomena in patch antenna array are investigated and according to the coupling characteristics, a simple rectangular slots placed in between the patch elements is proposed. Because of this, strong mutual coupling exists among these patch antenna of the arrays.
The proposed 3dmms has a negative permeability at 2. Antenna arrays assembly of radiating elements in electrical and geometrical configurations. Planar microstrip patch antenna array with gain enhancement. Mutual coupling reduction in patch antenna arrays using a planar compact ebg structure z. Triangular lattices for mutual coupling reduction in patch. The fork like ebg proposed in 15 reduced coupling by 6. The reduction of mutual coupling in the phased array is critical for the. Inserting a slot in the ground plane between the antenna elements is a simple method to reduce the mc, while adding the mls in the slot of the ground can further reduce the mc. Progress in electromagnetics research letters, 59, 6369 2016. Mutual coupling between the antenna elements in an antenna array is a classical problem, which is responsible for the degradation of array performance 2 34. Mutual coupling reduction in an array of patch antennas. The effect of mutual coupling on a microstrip printed. The nonplanar geometry is tackled by using eulers transformation towards the.
Mutual coupling reduction in patch antenna arrays using ebg. Prior to applying mbhies to the antenna array, the mutual coupling effects are examined by varying the patch separation d. A compact subdivided microstrip square patch array with. Farahani and mehdi veysi and manouchehr kamyab and a. Mutual coupling reduction of a mimo antenna array using 3. An equivalent circuit of the proposed structure is obtained through the reciprocity. Reduction of the mutual coupling in patch antenna arrays based on ebg by using a planar frequencyselective surface structure volume 9 issue 2 ehsan beiranvand, majid afsahy, vahid sharbati. Probe suppression in conformal phased array hema singh. Mutual coupling reduction in patch antenna arrays ieee xplore.
The performance of microstrip patch antenna system depends on the characteristics of the antenna element and the substrate as well as the feed configuration employed. However, the radiation patterns are slightly changed compared with the dual element microstrip antenna array with a slot in the ground. In large multilayer array networks the computational time and effort. A low mutual coupling design for array microstrip antennas. And also we can infer from the graph that the mutual coupling is a function of the distance between the elements, since it has been reduced monotonically as we progressed from 2nd element. In 8, the mutual coupling is calculated in the transmitting mode as one antenna in the array plays the role of the transmitting antenna and the others the role of the receiving antennas.
Meander lines mls in two configurations are presented to reduce the mutual coupling mc between two microstrip patch antenna elements. Reduction of manual coupling and sidelobe level in linear. Using polygonal defect in ground structure to reduce mutual coupling in microstrip array antenna. Ism band patch microstrip antennas and mutual coupling. Analysis of low mutual coupling compact multiband microstrip. The farfield radiation pattern of the microstrip antenna array is studied taking these mutual coupling effects into account. Reducing mutual coupling between elements of an antenna array is one of the main topics in array designs. Journal of electromagnetic waves and applications, 28 2, 194201 2014. Here the principal characteristics of interest are the antenna input impedance, mutual coupling, bandwidth, radiation pattern and return loss. Reduction of the mutual coupling in patch antenna arrays. Demonstrated to have lefthanded magnetic characteristics, the methodology uses complementary splitring resonators srrs placed horizontally between the patch and the. Mutual coupling is compensated by using the active scattering matrix.
The proposed design can be employed for reducing mutual coupling value of closely placed patch antenna. Broadband focusing using aperturecoupled microstrip. Antenna structure the setup model used to demonstrate the mutual coupling reduction is shown in figure 1a, where two identical microstrip antennas having resonant frequency of 2. A novel ebg array configuration is proposed, the band gap.
The results of numerical simulations show a significant reduction in the mutual coupling between the antenna elements. The main problem in microstrip patch antenna array is mutual coupling effect. Mutual coupling can significantly degrade the performance of an antenna array. Highly reduced mutual coupling between wideband patch. Whats more, realizing mutual coupling reduction while keeping the radiation patterns is very important. The proposed twoelement array antenna has a dimension of approximately 1. Reduction of the spatially mutual coupling between dual. The effect of mutual coupling is observed or modeled by varying the space between the antenna elements in the array. Figure 2 from mutual coupling reduction in patch antenna. Abstract in microstrip patch antenna array, the mutual coupling is very critical due to surface wave excitation. While designing an antenna array one of the main design issue designers face is mutual coupling effect. Mutual coupling reduction in patch antenna arrays using a ucebg superstrate abstract.
Mutual coupling effect leads to element radiation pattern distortion, side lobes higher than the desired and mismatch of individual. Figure 7 a plots the mutual coupling for various patch separations and figure 7 b plots the minimum coupling in both e and hplane directions for different distances at the resonant frequency of 3. Design of high impedance electromagnetic surfaces for. Jul 22, 2016 c copolarization mutual coupling coefficients s31 and d crosspolarization mutual coupling coefficients s41 of the patch antenna array black lines and that with proposed the decoupling. This paper investigates the performance of a microstrip antenna phased array embedded in an ebg. Furthermore, a model of linear array antenna consists of five microstrip patch. Mutual coupling reduction in patch antenna arrays using. This coupling effect is also known to directly or indirectly influence the steady state and. Mutual coupling reduction between printed dualfrequency antenna arrays. The reduction of this mutual coupling for microstrip patch antenna array is a major challenge. For array antennas, the change in antenna pattern from the case when a particular feeding structure is attached to the array and mutual impedances among elements are ignored in deducing the excitation to the case when the same feeding. Highly reduced mutual coupling between wideband patch antenna.
Hybrid method of analysis for aperturecoupled patch. Mutual coupling leads to variation in beam width, gain, directivity of antenna arrays. Return loss a and mutual coupling b for different spacing in the x direction with 5 rows iv. The main drawback of eplane coupled microstrip patch antenna arrays is that they possess the high excitation of surface waves. The antenna, built on a metamaterial substrate, showed significant size reduction and less mutual coupling in an array compared with similar arrays on conventional substrates. Conclusion in this paper, a metamaterial spiral resonator structure was used for reducing the mutual coupling between the elements of the microstrip array antenna. Pdf wide scan phased array patch antenna with mutual coupling. Design of microstrip patch antenna array using parasitic.
In this paper, meander line ml as a parasitic configuration is introduced to reduce the mutual coupling mc between two microstrip patch antenna. This letter describes a novel configuration of uniplanar compact electromagnetic bandgap ucebg structures to reduce mutual coupling between. Metasurface wall suppression of mutual coupling between. Tadjalli, journalieee antennas and wireless propagation. Mutual coupling between rectangular and triangular patches this section is devoted to the study of cases, focusing on configurations with the lowest mutual couplings. One of the issues in antenna arrays is the mutual coupling that occurs when two radiating elements are placed together. The subdivided microstrip patch antenna, as a consequence of size minimization, has reduced mutual coupling for a given elements spacing when used in phased array applications.
This is one of the limitations involved in antenna arrays. Figure 3 from mutual coupling reduction in patch antenna. Mutual coupling reduction in patch antenna arrays using a uc. The 3dmms consists of an upper mshaped patch and two lower ushaped patches, which are connected by two shorted pins. Mutual coupling is a natural in array and optimum nonzero value of mutual coupling is an important property and. Design of high impedance electromagnetic surfaces for mutual. The use of electromagnetic bandgap ebg structures built by microstrip technology is an attractive way to mitigate the mutual coupling problem. It is clear from this graph that mutual coupling is dramatically reduced after applying mswi. Mutual coupling reduction between closely placed microstrip. In this research, the effect of the antenna configuration in array on mutual coupling has been studied and the main purpose is to find the array configuration that provides the minimum. Mutual coupling reduction between closely spaced uslot patch. Much research has focused on the reduction of mutual coupling.
Dec 19, 2019 after loading the decoupling structures in the antenna array, the gain increased from 5. Mutual coupling reduction in an array of patch antennas using. Mutual coupling exhibits differently in transmitting and receiving antenna arrays and has to be treated differently. In the first configuration, one ml is inserted in the slot of the. Mutual coupling reduction in patch antenna arrays using a. Mutual coupling in conformal microstrip patch antenna. This approach does not require any external antenna, but it analyzes the array in opencircuit conditions, which usually has matched loads in practice. Mutual coupling reduction of a mimo antenna array using 3d. Mutual coupling reduction in patch antenna arrays by using a. But the values of the above parameters are affected by mutual coupling between the elements.
The effect of mutual coupling between elements in such an array is included in the analysis. Mutual coupling can significantly degrade the performance of. The effect of mutual coupling on a microstrip printed antenna. Therefore in order to increase the performance of the antenna array mutual coupling should reduce. Triangular lattices for mutual coupling reduction in patch antenna arrays. Mutual coupling reduction between patch antennas using. Mutual coupling reduction between closely spaced uslot.
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