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提出一种具有新型匹配网络的宽带高效率功率放大器,以及利用开路扇形微带线构成的紧凑型输出匹配网络,并给出了阻抗推导过程。该输出匹配网络在一定带宽条件下能满足晶体管的高效率所对应的阻抗设计空间要求。为了进一步拓展带宽,采用阶跃式阻抗匹配方法设计输入匹配网络。通过理论分析与仿真,最后设计并制作了一款频段为1~3.1 GHz的宽带高效率J类功率放大器。测试结果表明,在该频段内漏极效率为61.4%~70.2%,输出功率为39.3~41.7 dBm,增益为9.3~11.7 dB。 相似文献
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提出了一种基于5G 频段的宽带高效率F 类功率放大器。分析表明锥形微带线可以有效解决矩形微带线对于带宽的限制问题, 同时将锥形微带线加入谐波控制网络, 可以实现在一定频率范围内将二次谐波阻抗匹配至短路点附近, 三次谐波阻抗匹配至开路点附近, 从而有效解决了F 类功率放大器带宽和效率的问题。使用锥形微带线制作的功放, 实测结果表明: 在2.7 ~3.8GHz 的频带范围内, 漏极效率达到63% ~78%, 平均输出功率达到10W以上, 大信号增益达到10dB 以上。在5G 无线通信中, 该功放可以有效地发挥其宽带高效率的特点。 相似文献
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New broadband impedance matching circuits used to increase the impedance bandwidth of the microstrip antennas for transmit applications are proposed and analyzed. A microstrip patch operating at 10.5 GHz having 12.2% bandwidth has been utilized as a reference antenna. The impedance bandwidth of the antenna has been enhanced by using negative capacitance and inductance compensation networks from 12.22% to 16.96% and 24.50%, respectively. In addition, it has been shown that the active compensation significantly improves the radiation pattern 相似文献
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RongLin Li Bo Pan Traille A.N. Papapolymerou J. Laskar J. Tentzeris M.M. 《Antennas and Propagation, IEEE Transactions on》2008,56(2):312-318
A cavity-backed loop antenna is developed for producing broadband circularly polarized (CP) radiation. The antenna configuration consists of a slot loop and a strip loop. The slot loop radiates a CP wave at a lower frequency while the strip loop produces CP radiation at a higher frequency. A combination of the two frequencies leads to a bandwidth enhancement. The slot/strip loop antenna is fed by a single straight microstrip line. It is demonstrated that the cavity-backed slot/strip loop antenna can achieve an axial ratio (les 3 dB) bandwidth of 19% with good impedance matching. The antenna configuration is described and the operating principles for broadband circular polarization and impedance matching are analyzed. The antenna performance is confirmed by experimental results. 相似文献
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A novel compact and simple microstrip monopole antenna for 5 GHz wireless local area network (WLAN) operation is proposed. To excite a resonant mode in the operating band, a tuning strip is added to the antenna, which consists of a rectangular ring microstrip and a top loaded vertical strip, and is fed by a 50 /spl Omega/ microstrip line. The effects of the added strip to the impedance matching have been studied. A constructed prototype of the proposed antenna has been tested and bandwidth of about 930 MHz ranging from 5.03 to 5.96 GHz, monopole-like radiation pattern, and average gain of greater than 2.6 dBi over the operating band have been obtained. 相似文献
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提出了一款高增益低副瓣新型圆极化微带天线阵。单元天线采用叠层切角圆极化微带结构,通过八边形边界布局和顺序旋转交叠组阵技术,实现了天线阵方向性图的对称性和圆极化辐射性能的最优化;馈电网络采用威尔金森功分器和最大平坦式阻抗变换器实现不等功分宽带阻抗匹配,通过改进馈电方向寻求对称结构,简化了馈电网络的设计。制作了天线阵实物并进行了测量。测试结果表明:天线在3.2~4.6 GHz频段内S11<-10 dB,阻抗相对带宽36%;在3.8~4.5 GHz频段内顶点轴比小于3 dB,圆极化相对带宽17%;在4~4.4 GHz频段内天线增益均在15 dB以上,最高增益达17 dB。 相似文献
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针对传统八木天线体积过大,难以与其他载体共形,相对带宽很窄的问题,设计了一种宽带微带八木天线。天线采用一种比较简单的馈电方式减小天线的尺寸,利用附加寄生贴片、振子耦合枝节和金属化孔的方式展宽频带和改善天线的阻抗匹配。使用Ansoft公司高频结构仿真器(HFSS)对天线进行仿真设计和优化,并对实物进行测试。最后结果表明,所设计、制作的天线频段在1.81~2.57 GHz内,电压驻波比(VSWR)小于2,相对带宽为31%,在2.4 GHz频率处的增益大于9 dB。仿真和测试结果显示,该宽带微带八木天线基本达到设计要求。 相似文献
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微带阵列天线具有增益高、剖面低、体积小、重量轻、成本低、易共形等优势,为了克服其频带窄、交叉极化强的问题,文中采用偏置缝隙耦合馈电、上层贴片、并馈网络等措施设计了宽带多层微带阵列天线。在等效电路分析基础上,结合仿真验证,分析了关键参数对天线单元阻抗匹配的影响,得出了单元最佳结构尺寸。采用了灵活的等功分并馈网络实现了8×8布局、45°极化的微带阵列天线。仿真和实测结果表明:电压驻波比VSWR<2的阻抗带宽达到48.8%,半功率波束宽度HPBW>9.2°时增益大于18 dB,交叉极化电平低于-22 dB,同时具备较深的零深、较低的副瓣电平。 相似文献
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The design of an S-band, broadband, microstrip 3 dB, 90 degrees branchline coupler is described and measured results for a prototype version are given. The design uses broadbanding stubs and three branches, with the central branch split into two of twice the characteristic impedance and separated by half wavelength transmission lines. This is a new technique to improve the bandwidth of which a theoretical account was given by Mayer (see ibid., vol.26, no.18, p.1477-8, 1990). Measured results for the prototype coupler show return loss greater than 17 dB and isolation greater than 16.5 dB, over a percentage bandwidth of 45%.<> 相似文献
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Using a microstrip line employing periodically perforated ground metal (PPGM) on a GaAs monolithic microwave integrated circuit (MMIC), a highly miniaturised and broadband impedance transformer was developed for application to low impedance matching in broadband. Its size was 0.132 mm/sup 2/ on GaAs substrate, which was 2.3% of the one fabricated by a conventional microstrip line. The transformer showed good RF performance over a broadband including ultra-wideband. This is the first report of an on-chip broadband impedance transformer fabricated on MMIC. 相似文献
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研究设计了一款低剖面、宽带、高增益、低副瓣的定向平板天线。为了实现低剖面,采用了宽带微带天线单元、馈电网络等设计,定向天线整体采用印制板;为了实现低副瓣,采用阵列天线与馈电网络的一体化设计,用多层印制板加工技术实现天线单元间不等幅度的馈电精度,尽可能减少人工装配步骤,以降低装配误差。文中对设计的低副瓣定向天线进行了加工测试。测试结果表明,所研制天线的阻抗带宽为26.1%。在阻抗带宽范围内,可以实现最大增益大于23.6 dBi、E面和H面的副瓣电平分别小于-27.4 dB和-28.3 dB、前后比小于-42.2 dB。 相似文献
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提出了一种新颖的V形微带缝隙天线,地板上开一个直角V形缝隙,在V形缝隙的顶角处附加一个小直角三角形补偿隙,通过改变三角形补偿隙面积的大小可以对天线阻抗匹配进行优化,由基片另一侧的箭形微带线终端对缝隙单元馈电。这种天线易于实现宽带特性,设计简单,便于加工。文中给出了天线阻抗和方向图的计算结果,并给出了反射损耗和增益的实验结果。实测结果表明,该天线的阻抗带宽达到了43%,覆盖了1146~1776MHz的频率范围,-10dB阻抗带宽内增益值在4.5~6.5dB之间,平均增益约为5.5dB。 相似文献
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Yong-Xin Guo Kah-Wee Khoo Ling Chuen Ong 《Antennas and Propagation, IEEE Transactions on》2008,56(2):319-326
A novel 90deg broadband balun comprising a broadband 90deg Schiffman phase shifter is introduced as a means of enhancing the wideband circular polarization performance of dual-fed type microstrip antennas. The proposed 90deg broadband balun delivers good impedance matching, balanced power splitting and consistent 90deg (plusmn5deg) phase shifting, across a wide bandwidth (~57.5%). A circular patch antenna utilizing the proposed 90deg broadband balun is shown to attain measured impedance(S11< -10 dB) and axial ratio (AR < 3 dB) bandwidths of 60.24% and 37.7%, respectively, for the dual L-probe case; and 71.28% and 81.6% respectively, for the quadruple L-probe case. 相似文献
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设计了一种宽带圆极化介质谐振器天线,为一种鼠笼形的宽带一分四90毅相移功分微带馈电网络,采用缝隙耦合对介质谐振器顺序旋转耦合馈电。天线结构紧凑、加工简单,仿真和实测结果吻合良好,其阻抗带宽和低于3dB的轴比带宽重叠部分在1.09 GHz-1.83GHz、为50.7%。增益大于3dB 及轴比小于3dB 的波束宽度均达到90°。天线工作频率覆盖四大导航系统,包括中国的北斗系统、美国的GPS 系统、欧洲的伽利略(GALTLEO)系统和俄罗斯的格洛纳斯(GLONASS )系统的频段,天线可应用于全球卫星导航定位系统和无线宽带通信系统中。 相似文献