共查询到19条相似文献,搜索用时 187 毫秒
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设计了一种基于OTA的有源Gm-C复数带通滤波器,用以实现射频前端芯片中的中频滤波和镜像抑制功能,该滤波器采用Gyrator结构,将低通原型滤波器中的集总电感用有源电感进行替换,并依据复数变换理论,对浮地电容和接地电容进行复数变换,实现带通滤波器.滤波器中心频率为4.1 MHz,1 dB带宽2 MHz,带内增益13.27 dB,1.5倍带宽处抑制在40 dB以上,镜像抑制度40 dB.Gm-C滤波器集成度高,功耗低,适合于高频应用,是当前集成中频滤波器的热点. 相似文献
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设计并实现了基于0.18 μm CMOS工艺的2.4 GHz无线传感网(Wireless Sensor Network)射频接收机低中频有源复数带通滤波器.该滤波器采用基于积分器单元的复数带通滤波器结构,同时实现镜像抑制和信号滤波的功能.仿真结果表明,复数带通滤波器的中心频率为2 MHz,通带带宽为2.4 MHz,通带电压增益约为12.5 dB,镜像抑制大于30 dB,相邻信道阻带衰减大于40 dB,噪声系数小于15 dB,消耗电流为5 mA.通过系统验证,本设计各项性能均满足无线传感网射频接收机的设计要求. 相似文献
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针对低电源电压Gm-C复数滤波器线性度不足的问题,提出了一种使用大信号线性化技术的一阶复数带通滤波器。所提出的复数滤波器使用了不平衡差分对和自适应偏置电路两种线性化技术,通过扩展跨导相对恒定的输入电压范围提高滤波器的线性度。滤波器采用UMC 110 nm CMOS工艺设计,中心频率和带宽分别为2 MHz和1 MHz。Cadence仿真结果显示,在1.2 V电源电压下,滤波器功耗为229μW,镜像抑制比(IIR)为18 dB,线性度(输入三阶交调点IIP3)为9.53 dBm,总谐波失真(THD)为-55.7 dB。该复数滤波器电路结构简单、功耗较低,以期能广泛应用于低电源电压的接收机设计。 相似文献
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采用0.18μmCMOS工艺设计了一款应用在无线传网中的三阶级联有源RC复数带通滤波器,同时设计了自动频率调谐电路(AFT)。该滤波器采用的是切比雪夫逼近函数予以实现。在5比特数字控制码开关电容阵列的控制下,AFT电路即可完成对主体滤波器电路频率变化的校正。仿真结果显示,滤波器的中心频率稳定在2MHz,通带带宽为2MHz,镜像抑制比大于34dB,相邻信道阻带衰减大于34dB,通带纹波小于1dB,消耗电流为2.3mA,工作电源电压为1.8V。 相似文献
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杨形坚 《固体电子学研究与进展》1985,(2)
<正>镜像抑制混频器是通讯和其它电子系统中不可缺少的部件之一.一般达到镜像抑制的方法有两种,在混频器信号输入端设置带通滤波器(或带阻滤波器);另一种是在混频器设计中利用相位关系来区分中频输出是真正射频或镜频干扰信号,使有用中频信号输入到接收机,而镜像信号产生的干扰信号消耗或反射在匹配负载上.前者设计较简单,仅适用于高中频系统;但对工作频带较宽、频率捷变和低中频接收机系统就不适用.因此就只能采用后者,亦即移相型双平衡电路结构. 相似文献
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微带交指带通滤波器具有结构紧凑、易于批量生产的特点,适用于TVRO超外差接收机中作为镜像频率抑制滤波器。本文给出有关设计公式、设计实例。 相似文献
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分析了GPS接收机镜像信号抑制的要求,设计应用于低中频GPS接收机的镜像抑制复数滤波器.滤波器基于OTA-C双二次结构,通过线性变换实现频率搬移.采用了带源极负反馈的全差分跨导器以扩大输入线性范围.设计了基于环形振荡器的数字调谐锁相环以减小滤波器频率偏差.电路采用0.18μm CMOS工艺实现.测试结果表明,滤波器带宽为3.1MHz,偏移5MHz抑制为50dB,频率修调误差小于±1.5%.镜像抑制大于35dB.1.8V电源电压下滤波器和修正电路电流分别为0.82mA和0.23mA. 相似文献
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Vedran Furtula Herbert Zirath Mirko Salewski 《Journal of Infrared, Millimeter and Terahertz Waves》2013,34(12):824-836
A fundamental requirement for most mm-wave heterodyne receivers is the rejection of the input image signal which is located close to the local oscillator frequency. For this purpose we use a bandpass filter, which for heterodyne receivers is also called an image rejection filter. In this paper we present a systematic approach to the design of a waveguide bandpass filter with a passband from 100 to 110 GHz and upper rejection bandwidth in the range from 113 to 145 GHz. We consider two non-tunable filter configurations: the first one is relatively selective with 11 sections (poles) whereas the second one is simpler with 5 sections. We used established design equations to propose an initial guess for the geometries of the filters, optimized the geometries, constructed the filters using two different milling methods, measured their transmission and reflection characteristics, and compared the measurements with numerical simulations. Measurements of both filters agree well with simulations in frequency response and rejection bandwidth. The insertion loss of the 11-pole filter is better than 10 dB and that of the 5-pole filter is better than 5 dB. The 11-pole filter has a sharper attenuation roll-off compared with the 5-pole filter. The upper out-of-band rejection is better than 40 dB up to 145 GHz for the 11-pole filter and up to 155 GHz for the 5-pole filter. 相似文献
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Komurasaki H. Sano T. Heima T. Yamamoto K. Wakada H. Yasui I. Ono M. Miwa T. Sato H. Miki T. Kato N. 《Solid-State Circuits, IEEE Journal of》2003,38(5):817-825
This paper describes a single-chip RF transceiver LSI for 2.4-GHz-band Gaussian frequency shift-keying applications, such as Bluetooth. This chip uses a 0.18-/spl mu/m bulk CMOS process for lower current consumption. The LSI consists of almost all the required RF and IF building blocks: a transmit/receive antenna switch, a power amplifier, a low noise amplifier, an image rejection mixer, channel-selection filters, a limiter, a received signal strength indicator, a frequency discriminator, a voltage controlled oscillator, and a phase-locked loop synthesizer. The bandpass filter for channel selection was difficult to achieve since it operates at a low supply voltage. However, because large interference is roughly rejected at the output of the image rejection mixer and a wide-input-range bandpass filter with an optimized input bias is realized, the transceiver can operate at a supply voltage of 1.8 V. In the IF section, we adopted a circuit design using the minimum number of passive elements, resistors and capacitors, for a lower chip area of 10.2 mm/sup 2/. 相似文献
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Henkel F. Langmann U. Hanke A. Heinen S. Wagner E. 《Solid-State Circuits, IEEE Journal of》2002,37(12):1628-1635
This paper presents a quadrature bandpass /spl Sigma//spl Delta/ modulator with continuous-time architecture. Due to the continuous-time architecture and the inherent anti-aliasing filter, the proposed /spl Sigma//spl Delta/ modulator needs no additional anti-aliasing filter in front of the modulator in contrast to quadrature bandpass /spl Sigma//spl Delta/ modulators with switched-capacitor architectures. The second-order /spl Sigma//spl Delta/ modulator digitizes complex analog I/Q input signals at 1-MHz intermediate frequency and operates within a clock frequency range of 25-100 MHz. The modulator chip achieves a peak signal-to-noise-distortion ratio (SNDR) of 56.7 dB and a dynamic range of 63.8 dB within a 1-MHz signal bandwidth and at a clock frequency of 100 MHz. Furthermore, it provides an image rejection of at least 40 dB. The 0.65-/spl mu/m BiCMOS chip consumes 21.8 mW at 2.7-V supply voltage. 相似文献
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介绍了一种中频信号接收与处理电路设计,在研究了中频信号带通采样理论的基础上,设计了一种基于ADC+FPGA+DSP结构框架的中频信号接收与处理电路,对ADC转换器电路、FPGA及外围电路、DSP及其外围电路以及电源模块电路的设计进行了详细介绍。该中频信号接收与处理电路可以实现125MSPS的采样速率,FPGA和DSP的采用为后续信号处理提供了强大的硬件支持。因此,该中频信号接收与处理电路具有较高的实用价值。 相似文献
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A new photonic signal processor topology that simultaneously achieves both a high-Q and a high skirt selectivity and stopband attenuation filter response is presented. It is based on a novel dual-cavity bandpass optical structure in which two pairs of active fiber Bragg grating cavities are used with an optical gain offset to control the poles and stopband attenuation characteristics of the filter. This concept enables a large improvement in the filter stopband attenuation, rejection bandwidth, and skirt selectivity to be realized. Measured results demonstrate both a narrow bandpass bandwidth of 0.4% of center frequency and a skirt selectivity factor of 16.6 for 40 dB rejection, which corresponds to a 6.5-fold improvement in comparison to conventional single cavity high-Q structures. To our knowledge, this is the best skirt selectivity reported for a photonic bandpass filter to date. The new photonic filter structure has been experimentally verified and excellent agreement between measured and predicted responses is shown. 相似文献