基于超材料结构的定频波束可调天线设计

提出了一种新颖的波束可调天线。该天线辐射单元采用加载电容的超材料结构,相较于传统波导裂缝阵列天线的辐射缝隙,超材料辐射单元的尺寸缩小了76%;天线采用蚀刻有超材料结构的Rogers RT5880印刷电路板(PCB)作为天线辐射面,通过调整加载在超材料单元上的电容来调整波束指向。天线的测试结果与电磁仿真软件仿真结果接近。测试和仿真结果表明,天线工作在频率15 GHz,最大增益为11 dBi,辐射效率为80.8%,波束可调天线实现了-28°,-20°,-12°,-6°,6°, 13°和24°七种不同波束指向。     

一种适用于LTE 基站的宽频带双极化印刷偶极子天线

提出了一种适用于LTE 移动通信基站系统的低成本双极化偶极子基站天线辐射单元,天线采用0.8 mm板厚的FR4基板双层印制工艺。利用微带线垂直和折叠结构的辐射臂设计,有效地扩展了天线工作带宽,减小了天线物理尺寸。将两个偶极子单元垂直交叉构成±45°双极化天线。测试结果显示天线电压驻波比VSWR 小于1.5 的相对阻抗带宽为52.9%(1.705 ~2.93 GHz),隔离度大于19 dB,天线平均增益为8.67 dBi,半功率波束宽度为67°±8°。测试与仿真吻合较好,可应用于移动通信基站。     

一种改进的対拓Vivaldi天线设计

提出了一种新颖的対拓Vivaldi天线。该天线的辐射耀斑用新的复合指数曲线修正。为改善天线的辐射特性(增益,波束偏离和交叉极化),提出了一个新的引向器,该引向器由两个混合椭圆金属贴片构成。测试结果表明该天线在1到40GHz频率范围内增益>0dBi, 并且在15到40G频段内天线的增益>12dBi。在3到40GHz频率范围内,E面的波束偏离小于3°,并且在15到40GHz不超过2°。     

基于微机械工艺的60 GHz波束扫描天线阵

提出了一种应用于高速率无线通信的基于微机械工艺的波束扫描天线阵.基于微机械工艺的空气填充的同轴线结构能提供低损耗的矩形微同轴传输线和馈电网络设计.设计的传输线仿真和测试插入损耗均小于0.18 dB.仿真和测试结果吻合良好.波束扫描天线阵的尺寸为17.5×14.5×0.42 mm3, -10 dB带宽为10 GHz(55~65 GHz), 其带宽覆盖60 GHz标准的全频段.波束扫描角度分别为±35°和±11°.在60 GHz中心频点, 增益分别为11.8 dBi和12.1 dBi.     

一种小型宽带双极化5G基站天线

设计了一种适用于2G/3G/4G/5G移动通信的小型宽带±45°双极化基站天线。该天线由2对偶极子辐射片、2条微带馈线和1块反射板组成,辐射臂和微带馈线采用双面印刷工艺印刷在0.8 mm厚的FR4板,并固定放置于开有圆形槽的反射板上。对天线实物进行加工测试,测试结果表明,端口1工作频段为1.82～3.60 GHz,端口2工作频段为1.64～3.41 GHz;工作频段内,反射系数小于-10 dB,端口隔离度优于18 dB;交叉极化比在视轴方向大于17 dB,±60°方向大于15 dB;半功率波束65°左右,前后比优于18 dB,测试和仿真结果较吻合。所设计天线带宽宽,尺寸小,且制作工艺简单,成本低廉,适合批量生产,应用于5G移动通信基站中。     

一种倾斜波束双极化天线

提出了一种具有倾斜波束辐射特性的新型双极化天线。该双极化天线由两个正交的纺锤形偶极子 组成,根据准八木天线原理,在偶极子两侧加载寄生振子作为反射器和引向器,用以实现倾斜波束辐射。这种纺锤 形偶极子可以增加电流长度从而减小天线的整体尺寸。同时在每个偶极子贴片上蚀刻两个梯形槽,以实现良好的 阻抗匹配。另外,通过连接到同轴线的金属短截线对纺锤形偶极子进行激励,简化了天线馈电结构。测试结果表 明,天线的阻抗带宽为3. 36~3. 69 GHz(S11 <-10 dB),两个极化端口之间的隔离度大于16 dB,波束倾斜度为30°,波 瓣宽度约为85°,可适用于单侧大角度扫描阵列。     

Miniaturized LPDA Antenna for Portable Direction Finding Applications

In this letter, a miniaturized log‐periodic dipole array (LPDA) antenna operating from 1 GHz to 6 GHz is proposed for portable direction finding applications. To reduce the lateral size of an LPDA antenna, bow‐tie elements and a top‐loading technique are utilized and spacing factor is decreased to reduce the spacing between the LPDA elements. The proposed miniaturized LPDA antenna has the measured gain and front‐to‐back ratio ranging from 1.2 dBi to 3 dBi and from 7 dB to 22 dB, respectively.     

Cylindrical ring dielectric loaded horizontally polarized omnidirectional antenna for wideband radiation

A wideband horizontally polarized omnidirectional antenna with a cylindrical ring dielectric (CRD) loaded is proposed. Compared with the conventional alford-structure loop antenna (ASLA), the impedance and radiation pattern bandwidths are broadened by loading a CRD to the ASLA with two wing sections. The designed antenna is fabricated and measured, and good performance has been obtained. The measured reflection coefficient is less than −10 dB over the frequency band 1.63–2.8 GHz, i.e., 52.8%, which can cover 2G/3G/LTE band totally. The gain variation in all directions of horizontal plane is less than 1.4 dB in the whole band. The maximum gain is 1.56dBi throughout the operating band and it appears at 1.66 GHz. It is worth noting that the gain is around 1dBi and almost constant from 1.9 GHz to 2.7 GHz. Besides, the designed antenna has a compact size of 0.55λ × 0.55λ × 0.057λ, λ is for the lowest frequency of the operating band.     

Passive parasitic UWB antenna capable of switched beam‐forming in the WLAN frequency band using an optimal reactance load algorithm

We propose a switched beam‐forming antenna that satisfies not only ultra‐wideband characteristics but also beam‐forming in the WLAN frequency band using an ultra‐wideband antenna and passive parasitic elements applying a broadband optimal reactance load algorithm. We design a power and phase estimation function and an error correction function by re‐analyzing and normalizing all the components of the parasitic array using control system engineering. The proposed antenna is compared with an antenna with a pin diode and reactance load value, respectively. The pin diode is located between the passive parasitic elements and ground plane. An antenna beam can be formed in eight directions according to the pin diode ON (reflector)/OFF (director) state. The antenna with a reactance load value achieves a better VSWR and gain than the antenna with a pin diode. We confirm that a beam is formed in eight directions owing to the RF switch operation, and the measured peak gain is 7 dBi at 2.45 GHz and 10 dBi at 5.8 GHz.     

手持终端波束成形天线阵列的优化设计

设计了一款适用于移动手持终端的低剖面波束成形天线阵列。该天线阵列由八个结构相同的倒F天线组成,可以工作在GSM1900(1880~1920 MHz)、LTE2300(2300~2400 MHz)和LTE2500(2540~2620 MHz)三个频段。通过功率传输效率最大化理论,可以优化出该阵列在所需方向上的最佳激励。通过馈电电路板给8个天线单元提供优化的激励,可以将天线波束偏转到所需方向,并且保证天线在该方向上获得最大可能增益。天线阵列工作在2.45 GHz时,在x、y、z方向上的增益分别为7.80、6.03和7.20 dBi;相应地,在1.9 GHz时分别为6.67、5.27和6.05 dBi。     

Wideband to narrowband/dual band characteristics of monopole antenna using frequency selective surfaces

A monopole antenna having desirable transmission characteristics with high gain is proposed. The monopole antenna comprises 45° tilted square shaped patch and modified rectangular metallic ground plane on FR4 dielectric substrate. The proposed monopole antenna operates from 2.6 GHz to 9.7 GHz with maximum peak gain of 2.3 dBi. Now, a dual-layer aperture-type FSS is designed having a passband from 5.9 GHz to 9.2 GHz and incorporated with the proposed monopole antenna. Thus, the combination only covers the selective frequency band from 5.5 GHz to 8.7 GHz with a stable gain of around 5 dBi. Second, another FSS is designed, which has one stop-band from 4.1 GHz to 5.4 GHz and two passbands on the both sides of this stop-band. This combination does not work from 4.1 GHz to 5.5 GHz but covers dual band from 2.48 GHz to 3.3 GHz with a peak gain of 5 dBi and 5.5 GHz to 10 GHz with a peak gain of 5.5 dBi. Therefore, without modifying the antenna design, any tunable transmission band can be achieved by the proposed combination. The proposed antenna and FSS combination structure may be suitable for military wireless applications for its band selection characteristics.     

一种新型VHF双频宽带高增益全向天线

提出了一种工作在VHF频段的双频宽带中馈垂直极化高增益全向天线.天线采用中馈套筒天线结构形式,在天线上、下辐射体中部分别串接一个高频倒相线圈,天线底部加同轴扼流圈的设计方案.该天线在30 MHz～110 MHz和176 MHz～300MHz频带内具有良好的辐射特性,水平面增益为2～6dBi.     

宽带低交叉极化超材料漏波天线的设计

基于基片集成波导结构提出了一种新型双层电磁超材料单元，并验证了其左手特性。将超材料单元应用于漏波天线的设计，所设计的天线由15个双层电磁超材料单元组成。将设计好的天线进行加工测试，测试与仿真结果吻合较好，表明漏波天线的工作频带为7.20~12.70GHz，在工作频带内可实现从后向-78°到前向+80°的连续主波束扫描，天线在工作频带内的测试增益均大于10dBi，峰值增益为15.2dBi，3dB增益带宽达到50.2%。此外，该漏波天线具有很低的交叉极化电平，交叉极化始终比主极化低至少30dB。相比于新近文献报道的同类型超材料漏波天线，所设计的天线具有更加优越的电气性能。     

Unidirectional antenna composed of dipole and loop

A new printed structure composed of a dipole and a loop antenna for achieving a unidirectional antenna is proposed. The proposed antenna demonstrates that when an electric dipole and a magnetic dipole are excited simultaneously, a unidirectional radiation pattern can be obtained. With the absence of any ground plane or reflector, this directional printed antenna with single-layer structure can be used nowadays in small directional wireless systems and some handheld devices that need to radiate in a particular direction. The antenna operates at 2.4 GHz with an impedance bandwidth of 7.4% for S₁₁ < -10 dB and a peak measured gain of around 4.3 dBi.     

抑制共模噪声的SIW 平衡馈电差分缝隙天线阵*

提出一种利用差分天线在共模激励和差模激励下方向图不同来抑制共模噪声的方法,并基于该理论 设计了6×6 平衡馈电差分SIW 缝隙天线阵进行验证。该天线由6个宽边纵向SIW 缝隙天线子阵列组成。辐射缝隙 被设计为只在差模激励下辐射,达到抑制共模信号的目的。每个天线子阵采用平衡差分馈电方式,使用两个1分6 梳状功分器将6个子阵同时激励。整个天线使用标准PCB 工艺加工,为了测试共模和差模激励,分别设计了带有 180°相移的功分器和T型功分器用来生成差模和共模信号。在差模激励下,天线的最大增益为20.2dBi,S11幅值小 于-10dB 带宽为7.2%(39.6 ~43.8GHz),在共模激励下天线的最大增益为10.1dBi,在整个工作频段内S11幅值大于 -7dB。仿真和实验结果验证了该结构的SIW 缝隙天线对差模信号能够有效地辐射而对共模信号进行抑制。     

新型可重构临近耦合偶极子天线阵

提出了一种可重构的临近耦合印刷偶极子天线阵。其通过控制每个振子的间距和振子偏移中心馈线的距离实现方向图的改变,提出的可重构天线阵,将形成不同方向图的偶极子天线阵嵌套排布,并通过pin管开关切换不同的偶极子辐射单元组,从而实现天线方向图的重构,改变天线的最大辐射方向。仿真结果表明在9.8 GHz的中心频点上,该天线可实现最大辐射方向在0°和40°上切换:波束指向为0°方向时,最大增益为12 dBi;为40°时,最大增益为8.7 dBi,两种工作状态下天线输入端s11均优于-30 dB,匹配良好。     

一种适用于LTE和Sub-6 GHz频段的宽带双极化基站天线

提出了一种适用于LTE和Sub-6 GHz频段的紧凑型双极化基站天线辐射单元,辐射振子臂采用1.2 mm板厚的FR4基板双层印制工艺。利用在双极化辐射单元上方加载寄生单元的方式来扩展天线工作频带。实物测试结果显示天线工作频段可连续覆盖LTE(1.8 GHz^2.7 GHz)和5G的Sub-6 GHz频段(3.3 GHz^3.7 GHz),带内电压驻波比小于1.8,隔离度大于20 dB。天线最高增益为9.42 dBi,半功率波束宽度为60°±9°。测试和仿真结果吻合较好。可应用于4G和5G移动通信基站。     

一种单层贴片式双频双极化滤波天线

设计了一种单层式跨频段双频双极化滤波天线。该天线在同一平面上的高频低频辐射贴片共用一个馈电端口,且均可以在两个垂直方向馈电实现交叉方向的线极化辐射。该天线通过在馈电点与低频辐射贴片之间插入一个低通滤波器,明显提高了高频辐射贴片的交叉极化隔离度。研究结果表明,带滤波结构的天线在两个频率点的反射系数小于-20 dB,4.9 GHz的最大增益大于4.8 dBi,26 GHz的最大增益11.7 dBi,〖JP2〗两个辐射频率的辐射方向图均体现良好的线极化特性,且主极化比交叉极化大20 dBi。该天线可作为未来微波与毫米波共用的5G通信终端天线或5G通信基站的MIMO天线阵元,相关技术和结论对于研制一体化集成的双频交叉极化相控阵天线也有重要参考价值。     

Novel Shorted Meander‐Line USB Dongle Antenna with a Compact Ground Plane

This letter presents the design of a novel multiband USB dongle antenna with a compact ground plane. The radiating patch is composed of a modified meander‐line monopole and a shorted loop to generate a dual‐broadband resonance. The proposed antenna supports WiBro, Bluetooth, WLAN, WiMAX, and S‐DMB services. The total dimensions of the fabricated antenna are 10 mm × 45 mm × 1 mm, the most compact size among multiband USB dongle antennas reported to date. The measured 10 dB reflection loss bandwidths are 20.8% (2.24 GHz to 2.76 GHz) and 20.2% (4.86 GHz to 5.95 GHz). The measured peak gain is 2.97 dBi, and efficiency is higher than 58%. In addition, the radiation pattern approximates an omnidirectional pattern.     

Radiation performance improvement of wideband microstrip antenna array using wideband AMC structure

In this paper, the radiation performance of an antenna array is improved by designing a new wideband artificial magnetic conductor (AMC). The proposed AMC surface operates at the frequency of 3 GHz with ±90^° reflection phase bandwidth of 22%. In order to identify the key design parameters of the AMC structure, a parametric study is performed. To improve the radiation performance of the antenna array, an AMC reflector is developed through utilizing an array of 2 × 8 periodic patches of AMC unit cells. By this technique, the front to back ratio of the designed antenna array is enhanced about 16.27 dB. It is concluded that tuning of the AMC dimensions for controlling the reflection coefficient at each port of antenna array during beam steering is necessary. Because of the using of the AMC surfaces as a reflector instead of conventional PEC surfaces, size reduction of the antenna array in the order of 20% is achieved. In this study, a circuit model for single element of the antenna array with considering AMC loading effect is introduced, which predicts the bandwidth behaviour of the proposed antenna. The final designed antenna array exhibits low level of cross polarization making it well‐suited for tracking radars and electronic warfare applications. The proposed antenna with the AMC reflector is fabricated and measured. The measured ?10 dB impedance bandwidth and peak gain of the proposed antenna is 20% (2.7‐3.25 GHz) and 13.4 dBi, respectively, which are compatible with the simulation results.