Antennas are an indispensable element in wireless networks. For long-distance wireless communication, antenna gains need to be very strong (highly directive) because the signal from the antenna loses a lot of str...Antennas are an indispensable element in wireless networks. For long-distance wireless communication, antenna gains need to be very strong (highly directive) because the signal from the antenna loses a lot of strength as it travels over long distances. This is true in the military with missile, radar, and satellite systems, etc. Antenna arrays are commonly employed to focus electromagnetic waves in a certain direction that cannot be achieved perfectly with a single-element antenna. The goal of this study is to design a rectangular microstrip high-gain 2 × 1 array antenna using ADS Momentum. This microstrip patch array design makes use of the RT-DUROID 5880 as a substrate with a dielectric constant of 2.2, substrate height of 1.588 mm, and tangent loss of 0.001. To achieve efficient gain and return loss characteristics for the proposed array antenna, RT-Duroid is a good choice of dielectric material. The designed array antenna is made up of two rectangular patches, which have a resonance frequency of 3.3 GHz. These rectangular patches are excited by microstrip feed lines with 13 mm lengths and 4.8 mm widths. The impedance of the patches is perfectly matched by these transmission lines, which helps to get better antenna characteristics. At a resonance frequency of 3.3 GHz, the suggested antenna array has a directivity of 10.50 dB and a maximum gain of 9.90 dB in the S-band. The S parameters, 3D radiation pattern, directivity, gain, and efficiency of the constructed array antenna are all available in ADS Momentum.展开更多
Due to the shared nature of the wireless medium, the performance of wireless sensor network is often limited by both internal interference and external interference. The internal interference is that simultaneous traf...Due to the shared nature of the wireless medium, the performance of wireless sensor network is often limited by both internal interference and external interference. The internal interference is that simultaneous traffic activity by neighboring nodes in the same network, while the external interference is from wireless transmissions by other types of devices, such as Wi-Fi and Bluetooth nodes. In this paper, we present two channel hopping algorithms for multichannel, single-radio wireless sensor networks. The first algorithm achieves collision-free transmission environment while do not introduce extra control overhead. The second algorithm, in addition to reducing internal interference effects, reduces the external interference effects from Wi-Fi devices. Simulation results show that both of them significantly improve performance in wireless sensor network.展开更多
In this paper,a sparse nonuniform rectangular array based on spatially spread electromagnetic vector sensor(SNRASSEMVS)is introduced,and a method for estimating 2D-direction of arrival(DOA)and polarization is devised....In this paper,a sparse nonuniform rectangular array based on spatially spread electromagnetic vector sensor(SNRASSEMVS)is introduced,and a method for estimating 2D-direction of arrival(DOA)and polarization is devised.Firstly,according to the special structure of the sparse nonuniform rectangular array(SNRA),a set of accurate but ambiguous direction-cosine estimates can be obtained.Then the steering vector of spatially spread electromagnetic vector sensor(SSEMVS)can be extracted from the array manifold to obtain the coarse but unambiguous direction-cosine estimates.Finally,the disambiguation approach can be used to get the final accurate estimates of 2DDOA and polarization.Compared with some existing methods,the SNRA configuration extends the spatial aperture and refines the parameters estimation accuracy without adding any redundant antennas,as well as reduces the mutual coupling effect.Moreover,the proposed algorithm resolves multiple sources without the priori knowledge of signal information,suffers no ambiguity in the estimation of the Poynting vector,and pairs the x-axis direction cosine with the y-axis direction cosine automatically.Simulation results are given to verify the effectiveness and superiority of the proposed algorithm.展开更多
The circular sector patch antenna is studied in C-band (4 GHz - 8 GHz). In this paper, we present steps of designing the circular sector antenna then a comparison with a rectangular antenna in literature. High Frequen...The circular sector patch antenna is studied in C-band (4 GHz - 8 GHz). In this paper, we present steps of designing the circular sector antenna then a comparison with a rectangular antenna in literature. High Frequency Structure Simulator (HFSS) software is used to compute the gain, axial ratio, radiation pattern, and return loss S11 of proposed antenna. Based on the designed patch antenna, many phased arrays will be simulated using HFSS. The impact of distance between element, number of element and phase will be checked. Obtained results are analyzed and compared with literature.展开更多
A novel multi-band end-fire antenna array was designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical antenna dimensions and the design was optimized using a 3D elec...A novel multi-band end-fire antenna array was designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical antenna dimensions and the design was optimized using a 3D electromagnetic finite-element solver. The measured results were in good agreement with the designed results. The proposed antenna array exhibits multi-band capabilities which can be potentially used for applications that require a multi-band end-fire radiation pattern.展开更多
文摘Antennas are an indispensable element in wireless networks. For long-distance wireless communication, antenna gains need to be very strong (highly directive) because the signal from the antenna loses a lot of strength as it travels over long distances. This is true in the military with missile, radar, and satellite systems, etc. Antenna arrays are commonly employed to focus electromagnetic waves in a certain direction that cannot be achieved perfectly with a single-element antenna. The goal of this study is to design a rectangular microstrip high-gain 2 × 1 array antenna using ADS Momentum. This microstrip patch array design makes use of the RT-DUROID 5880 as a substrate with a dielectric constant of 2.2, substrate height of 1.588 mm, and tangent loss of 0.001. To achieve efficient gain and return loss characteristics for the proposed array antenna, RT-Duroid is a good choice of dielectric material. The designed array antenna is made up of two rectangular patches, which have a resonance frequency of 3.3 GHz. These rectangular patches are excited by microstrip feed lines with 13 mm lengths and 4.8 mm widths. The impedance of the patches is perfectly matched by these transmission lines, which helps to get better antenna characteristics. At a resonance frequency of 3.3 GHz, the suggested antenna array has a directivity of 10.50 dB and a maximum gain of 9.90 dB in the S-band. The S parameters, 3D radiation pattern, directivity, gain, and efficiency of the constructed array antenna are all available in ADS Momentum.
基金supported by the Natural Science Foundation of China(No.61574035)National Natural Science Foundation of China(No.61550110244)
文摘Due to the shared nature of the wireless medium, the performance of wireless sensor network is often limited by both internal interference and external interference. The internal interference is that simultaneous traffic activity by neighboring nodes in the same network, while the external interference is from wireless transmissions by other types of devices, such as Wi-Fi and Bluetooth nodes. In this paper, we present two channel hopping algorithms for multichannel, single-radio wireless sensor networks. The first algorithm achieves collision-free transmission environment while do not introduce extra control overhead. The second algorithm, in addition to reducing internal interference effects, reduces the external interference effects from Wi-Fi devices. Simulation results show that both of them significantly improve performance in wireless sensor network.
基金This work was supported by the innovation project of Science and Technology Commission of the Central Military Commission。
文摘In this paper,a sparse nonuniform rectangular array based on spatially spread electromagnetic vector sensor(SNRASSEMVS)is introduced,and a method for estimating 2D-direction of arrival(DOA)and polarization is devised.Firstly,according to the special structure of the sparse nonuniform rectangular array(SNRA),a set of accurate but ambiguous direction-cosine estimates can be obtained.Then the steering vector of spatially spread electromagnetic vector sensor(SSEMVS)can be extracted from the array manifold to obtain the coarse but unambiguous direction-cosine estimates.Finally,the disambiguation approach can be used to get the final accurate estimates of 2DDOA and polarization.Compared with some existing methods,the SNRA configuration extends the spatial aperture and refines the parameters estimation accuracy without adding any redundant antennas,as well as reduces the mutual coupling effect.Moreover,the proposed algorithm resolves multiple sources without the priori knowledge of signal information,suffers no ambiguity in the estimation of the Poynting vector,and pairs the x-axis direction cosine with the y-axis direction cosine automatically.Simulation results are given to verify the effectiveness and superiority of the proposed algorithm.
文摘The circular sector patch antenna is studied in C-band (4 GHz - 8 GHz). In this paper, we present steps of designing the circular sector antenna then a comparison with a rectangular antenna in literature. High Frequency Structure Simulator (HFSS) software is used to compute the gain, axial ratio, radiation pattern, and return loss S11 of proposed antenna. Based on the designed patch antenna, many phased arrays will be simulated using HFSS. The impact of distance between element, number of element and phase will be checked. Obtained results are analyzed and compared with literature.
文摘A novel multi-band end-fire antenna array was designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical antenna dimensions and the design was optimized using a 3D electromagnetic finite-element solver. The measured results were in good agreement with the designed results. The proposed antenna array exhibits multi-band capabilities which can be potentially used for applications that require a multi-band end-fire radiation pattern.
