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1.
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   

2.
A new “half-RF” architecture incorporates a polyphase filter in the signal path to allow the use of a local oscillator frequency equal to half the input frequency. The receiver performs 90 $^{circ}$ phase shift and two downconversion steps to produce quadrature baseband outputs. The transmitter upconverts the quadrature baseband signals in two steps, applies the results to a polyphase filter, and sums its outputs. Each path employs a dedicated 30-GHz oscillator and is fabricated in 90-nm CMOS technology. The receiver achieves a noise figure of 5.7–7.1 dB and gain/phase mismatch of 1.1 dB/2.1$^{circ}$ while consuming 36 mW. The transmitter produces a maximum output level of $-$7.2 dBm and an image rejection of 20 dB while drawing 78 mW.   相似文献   

3.
A 5.7 GHz downconversion mixer is demonstrated in this letter using 0.35 mum SiGe BiCMOS technology. A quarter-wavelength coupled line and two center-tapped transformers are utilized to generate differential quadrature LO signals. A miniaturized Marchand balun is placed before the common-base-configured RF input stage of each Gilbert mixer to generate balanced RF signals. All the reactive passive elements are placed directly on the standard silicon substrate. The 5.7 GHz downconverter achieves 7 dB conversion gain, 26dBm 1dB, and 18dBm IIP3 at the power consumption of 3.875 mW and 2.5 V supply voltage.  相似文献   

4.
We report an ultra-low-voltage RF receiver for applications in the 2.4 GHz band, designed in a 90 nm CMOS technology. The sliding-IF receiver prototype includes an LNA, an image-reject LC filter with single-ended to differential conversion, an RF mixer, an LC IF filter, a quadrature IF mixer, RF and IF LO buffers, and an I/Q baseband section with a VGA and a low-pass channel-select filter in each path, all integrated on-chip. It has a programmable overall gain of 30 dB, noise figure of 18 dB, out-of-channel IIP3 of -22 dBm. The 3.4 mm2 chip consumes 8.5 mW from a 0.5 V supply.  相似文献   

5.
On-chip transformers are best suited to lower the supply voltage in RF integrated circuits. A design method to achieve a high current gain with an on-chip transformer operating in resonance is presented. The proposed method will be proven analytically and has been applied to a downconversion mixer. Thereby part of the overall gain of the mixer has been shifted from the RF input stage to the transformer. Thus, the power consumption has been reduced and, in spite of the low supply voltage, moderate linearity has been achieved. Although the transformer has a bandpass behavior, a 3-dB bandwidth of 900 MHz at a center frequency of 2.5 GHz has been achieved. The downconversion mixer has been realized in 0.13-mum CMOS. It consumes 1.6 mW from a 0.6-V supply. A gain of +5.4 dB, a third-order intercept point of -2.8 dBm, an input 1-dB compression point of -9.2 dBm, and a single-sideband noise figure of 14.8 dB have been achieved  相似文献   

6.
Calibration techniques of active BiCMOS mixers   总被引:1,自引:0,他引:1  
This paper describes calibration techniques for downconversion mixers used in integrated direct-conversion receivers. A method of achieving a high even-order intermodulation rejection is presented. Using the method presented, the receiver second-order input intercept point (IIP2) can always be improved by more than 20 dB. The minimum achieved receiver IIP2 after calibration is +38 dBm. A technique to enhance the I/Q-amplitude balance between the quadrature channels is also introduced. A single-balanced adjustable mixer is implemented as a part of a prototype direct-conversion receiver. The receiver chip consists of a low-noise amplifier, mixers and calibration circuitry, a divide-by-two circuit, local oscillator (LO) buffers for LO generation, and active baseband filters. The chip is fabricated using a 0.35-μm SiGe BiCMOS process and is characterized at 900 MHz  相似文献   

7.
A 900 MHz homodyne receiver front-end bipolar chip is presented. The circuit consists of a low-noise amplifier and two double-balanced mixers for in-phase and quadrature channels. The power supply voltage is 3 V and power dissipation is 28 mW. The measured performance includes 33.5 dB voltage gain, a 3.1 dB noise figure, -13 dBm input referred IP3, -95 dB LO leakage into the RF port on wafer probing, and less than 0.1 dB I/Q magnitude imbalance  相似文献   

8.
A quadrature cascaded modulator with continuous-time loop filters is presented for a digital multi-stream FM radio receiver. The ADC achieves a dynamic range of 77 dB and 20 MHz bandwidth centered on an intermediate frequency of 10.5 MHz and is sampling at 340 MHz. The cascaded modulator comprises programmable analog second-order quadrature filters and a digital quadrature noise cancellation filter. The 0.5 chip in 90 nm CMOS consumes 56 mW from a 1.2 V supply.  相似文献   

9.
ΣΔ modulation with integrated quadrature mixing is used for analog-to-digital (A/D) conversion-of a 10.7-MHz IF input signal in an AM/FM radio receiver. After near-zero IF mixing to a 165 kHz offset frequency, the I and Q signals are digitized by two fifth-order, 32 times oversampling continuous-time ΣΔ modulators. A prototype IC includes digital filters for decimation and the shift of the near-zero-IF to dc. The baseband output signal has maximum carrier-to-noise ratios of 94 dB in 9 kHz (AM) and 79 dB in 200 kHz (FM), with 97 and 82 dB dynamic range, respectively. The IM3 distance is 84 dB at full-scale A/D converter input signal. Including downconversion and decimation filtering, the IF A/D conversion system occupies 1.3 mm2 in 0.25-μm standard digital CMOS. The ΣΔ modulators consume 8 mW from a 2.5-V supply voltage, and the digital filters consume 11 mW  相似文献   

10.
A charge-domain quadrature sampling circuit realization in 0.35 /spl mu/m CMOS is presented. The circuit downconverts a real-valued IF input signal with a nominal frequency of 50 MHz into baseband quadrature components by decimation. Based on multiple integrative sampling of charge, the circuit integrates a 192-tap complex bandpass finite-impulse response filtering function into the sampling operation providing 18 dB of built-in anti-aliasing suppression for the nearest unwanted frequencies aliasing to dc and over 36 dB of image band rejection on the 923-kHz 3-dB bandwidth of the circuit. The measured third-order input intercept point is + 25 dBV at 50 MHz, while the spurious-free dynamic range is more than 66 dB up to 100-MHz IF input frequency. The power consumption excluding output buffers is 30 mW from a 3.3-V supply.  相似文献   

11.
A fully differential low-voltage low-power downconversion mixer using a TSMC 0.18-mum CMOS logic process is presented in this letter. The mixer was designed with a four-terminal MOS transistor, the radio-frequency (RF) and local-oscillator signals apply to the gate and bulk of the device, respectively while the intermediate frequency (IF) signals output was from the drain. The mixer features a maximum conversion gain of 5.7dB at 2.4 GHz, an ultra low dc power consumption of 0.48 mW, a noise figure of 15 dB, and an input IP of 5.7 dBm. Moreover, the chip area of the mixer core is only 0.18 times 0.2 mm2. The measured 3-dB RF frequency bandwidth is from 0.5 to 7.5 GHz with an IF of 100 MHz, and it is greatly suitable for low-power in wireless communication.  相似文献   

12.
This paper presents a fully integrated dual-antenna phased-array RF front-end receiver architecture for 60-GHz broadband wireless applications. It contains two differential receiver chains, each receiver path consists of an on-chip balun, agm-boosted current-reuse low-noise amplifier (LNA), a sub-harmonic dual-gate down-conversion mixer, an IF mixer, and a baseband gain stage. An active all-pass filter is employed to adjust the phase shift of each LO signal. Associated with the proposed dual conversion topology, the phase shift of the LO signal can be scaled to one-third. Differential circuitry is adopted to achieve good common-mode rejection. The gm-boosted current-reuse differential LNA mitigates the noise, gain, robustness, stability, and integration challenges. The sub-harmonic dual-gate down-conversion mixer prevents the third harmonic issue in LO as well. Realized in a 0.13-mum 1P8M RF CMOS technology, the chip occupies an active area of 1.1 times 1.2 mm2. The measured conversion gain and input P1 dB of the single receiver path are 30 dB and -27 dBm , respectively. The measured noise figure at 100 MHz baseband output is around 10 dB. The measured phased array in the receiver achieves a total gain of 34.5 dB and theoretically improves the receiver SNR by 4.5 dB. The proposed 60 GHz receiver dissipates 44 mW from a 1.2 V supply voltage. The whole two-channel receiver, including the vector modulator circuits for built-in testing, consumes 93 mW from a 1.2 V supply voltage.  相似文献   

13.
韩洪征  王志功 《电子工程师》2008,34(1):22-25,46
介绍了一种应用于IEEE802.11b/g无线局域网接收机射频前端的设计。基于直接下变频的系统架构。接收机集成了低噪声放大器、I/Q下变频器、去直流偏移滤波器、基带放大器和信道选择滤波器。电路采用TSMC0.18μm CMOS工艺设计,工作在2.4GHz ISM(工业、科学和医疗)频段,实现的低噪声放大器噪声系数为0.84dB,增益为16dB,S11低于-15dB,功耗为13mW;I/Q下变频器电压增益为2dB,输入1dB压缩点为-1 dBm,噪声系数为13dB,功耗低于10mw。整个接收机射频前端仿真得到的噪声系数为3.5dB,IIP3为-8dBm,IP2大于30dBm,电压增益为31dB,功耗为32mW。  相似文献   

14.
A 5.2-GHz 11-dB gain, IP/sub 1 dB/=-17 dBm and IIP/sub 3/=-10 dBm double-quadrature Gilbert downconversion mixer with polyphase filters is demonstrated by using GaInP/GaAs heterojunction bipolar transistor (HBT) technology. The image rejection ratio is better than 40 dB when LO=5.17 GHz and intermediate frequency (IF) is in the range of 15 MHz to 40 MHz. The Gilbert downconverter has four-stage RC-CR IF polyphase filters for image rejection. Polyphase filters are also used to generate local (LO) and radio frequency (RF) quadrature signals around 5 GHz in the double-quadrature downconverter because GaAs has accurate thin film resistors and the low parasitic semi-insulating substrate.  相似文献   

15.
An integrated 2.4 GHz CMOS receiver front-end according to the IEEE 802.15.4 standard is presented in this paper. It integrates the overall RF part, from the balun up to the first stage of the channel filter, as well as the cells for the LO signal conditioning. The proposed architecture is based on a 6 MHz low-IF topology, which uses an inductorless LNA and a new clocking scheme for driving a passive mixer. When integrated in a 90 nm CMOS technology, the receiver front-end exhibits an area of only 0.07 mm2, or 0.23 mm2 when including an input integrated balun. The overall chip consumes 4 mA from a single 1.35 V supply voltage and it achieves a 35 dB conversion gain from input power in dBm to output voltage in dBvpk, a 7.5 dB NF value, -10 dBm of IIP3 and more than 32 dB of image rejection.  相似文献   

16.
A Complex Image Rejection Circuit With Sign Detection Only   总被引:2,自引:0,他引:2  
In direct-conversion receivers, radio frequency (RF) signals are down-converted to low or zero intermediate frequency (IF) using complex in-phase and quadrature (I/Q) mixers with no prior image filtering. Due to I/Q path gain and phase errors, image leaks into the signal band during the down-conversion process. A generic image rejection algorithm is proposed to reject image in the baseband using a zero-forcing sign-sign adaptive feedback concept. The orthonormal property of complex I/Q channels is exploited to update their gain and phase errors by detecting only four signs, and image is corrected with four multiplications and two additions. The proposed image rejection algorithm can be implemented in a digital, analog, or hybrid form. A complex baseband sample and hold (S/H) with a digital error detector, which is a hybrid example, achieves an image rejection of 65 dB while sampling at 40 MS/s. The prototype chip fabricated in 0.18-mum CMOS occupies 800times450 mum2, and consumes 23 mW at 1.8 V  相似文献   

17.
提出了一种低电压高增益CMOS下变频混频器的新结构.这个结构避免了堆叠晶体管,因此可以在低电压下工作.在LO信号的频率为1.452GHz,RF信号频率为1.45GHz的情况下,仿真结果表明:混频器的增益为15dB,ⅡP3为-4.5dBm,NF为17dB,最大瞬态功耗为9.3mW,直流功耗为9.2mW.并对该混频器的噪声特性和线性度进行了分析.  相似文献   

18.
In this paper, an X-band CMOS single chip integrating 16 building blocks is developed for frequency modulation continuous wave radar application. The quadrature and monopulse transceiver consists of a voltage-controlled oscillator, amplifiers, Wilkinson power dividers, 90deg hybrid low-noise amplifiers, rat-race hybrid, a single-pole double-throw switch, an active bandpass filter (BPF), and mixers. The transceiver is fabricated in a standard mixed-signal/RF bulk 0.18-mum CMOS technology with a chip area of 2.6 mm 3.3 mm, including contact pads. The transceiver is implemented by meandered complementary-conducting-strip transmission lines demonstrating their capability of miniaturizing circuits such as 90deg hybrid and rat-race hybrid with 95% and 98% size reduction compared to the prototype designs, respectively. The active BPF consumes 4.5 mW achieving 0-dB insertion loss at the passband. The total power consumption of the transceiver is 0.35 W. Output power of the transmitter is 1 dBm with a 35-dB second harmonic suppression. Moreover, the on-chip isolations between T/R in this compacted transceiver are more than 60 dB. The measured receiver gain and NF are -4.5 and 11.5 dB, respectively. Finally, the obtained in-phase and quadrature signals demonstrate 0.6-dB amplitude and 7deg phase imbalance.  相似文献   

19.
This paper describes a fully integrated digital-spread spectrum transceiver chip fabricated through MOSIS in 1.2 μm CMOS. It includes a baseband spread spectrum transmitter and a coherent intermediate frequency (IF) receiver consisting of a Costas loop, an acquisition loop for the pseudo-noise (PN) sequence, and a clock recovery loop with a 406.4 MHz onchip numerically controlled oscillator (NCO). The transceiver is capable of operating at a maximum IF sampling rate of 50.8 MS/s and a maximum chip rate of 12.7 R Mchips/s (Mcps) with selectable data rates of 100, 200, 400, and 800 kbps. At the maximum operating speed of 50.8 R MS/s, it dissipates 1.1 W. In an additive white Gaussian noise channel the IF receiver achieves a receiver output SNR within 1 dB of theory and can acquire code with a wide range of input SNR from -17 dB to over 30 dB. The transceiver chip has been interfaced to an RF up/down converter to demonstrate a wireless voice/data/video link operating in the 902-928 MHz band  相似文献   

20.
A down-conversion in-phase/quadrature (I/Q) mixer employing a folded-type topology, integrated with a passive differential quadrature all-pass filter (D-QAF), in order to realize the final down-conversion stage of a 60 GHz receiver architecture is presented in this work. Instead of employing conventional quadrature generation techniques such as a polyphase filter or a frequency divider for the local oscillator (LO) of the mixer, a passive D-QAF structure is employed. Fabricated in a 65 nm CMOS process, the mixer exhibits a voltage gain of 7-8 dB in an intermediate frequency (IF) band ranging from 10 MHz-1.75 GHz. A fixed LO frequency of 12 GHz is used to down-convert a radio frequency (RF) band of 10.25-13.75 GHz. The mixer displays a third order input referred intercept point (IIP3) ranging from -8.75 to -7.37 dBm for a fixed IF frequency of 10 MHz and a minimum single-sideband noise figure (SSB-NF) of 11.3 dB. The mixer draws a current of 6 mA from a 1.2 V supply voltage dissipating a power of 7.2 mW.  相似文献   

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