1,150 research outputs found

    Comparison of the Image Rejection between the Passive and the Gilbert Mixer

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    This paper presents a comparison of the image rejection between Gilbert mixer and the passive mixer. A simple model for mixers is set up, and the image rejection performance of passive and Gilbert mixer is analyzed based on it. Simulations and calculations were done to compare the image rejection of the two mixers. The results show that the Gilbert mixer, comparing with the passive one, shows a stronger rejection to the amplitude error of the quadrature signals at its input

    A Fully-Integrated Reconfigurable Dual-Band Transceiver for Short Range Wireless Communications in 180 nm CMOS

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    © 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.A fully-integrated reconfigurable dual-band (760-960 MHz and 2.4-2.5 GHz) transceiver (TRX) for short range wireless communications is presented. The TRX consists of two individually-optimized RF front-ends for each band and one shared power-scalable analog baseband. The sub-GHz receiver has achieved the maximum 75 dBc 3rd-order harmonic rejection ratio (HRR3) by inserting a Q-enhanced notch filtering RF amplifier (RFA). In 2.4 GHz band, a single-ended-to-differential RFA with gain/phase imbalance compensation is proposed in the receiver. A ΣΔ fractional-N PLL frequency synthesizer with two switchable Class-C VCOs is employed to provide the LOs. Moreover, the integrated multi-mode PAs achieve the output P1dB (OP1dB) of 16.3 dBm and 14.1 dBm with both 25% PAE for sub-GHz and 2.4 GHz bands, respectively. A power-control loop is proposed to detect the input signal PAPR in real-time and flexibly reconfigure the PA's operation modes to enhance the back-off efficiency. With this proposed technique, the PAE of the sub-GHz PA is improved by x3.24 and x1.41 at 9 dB and 3 dB back-off powers, respectively, and the PAE of the 2.4 GHz PA is improved by x2.17 at 6 dB back-off power. The presented transceiver has achieved comparable or even better performance in terms of noise figure, HRR, OP1dB and power efficiency compared with the state-of-the-art.Peer reviewe

    Integrated phased array systems in silicon

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    Silicon offers a new set of possibilities and challenges for RF, microwave, and millimeter-wave applications. While the high cutoff frequencies of the SiGe heterojunction bipolar transistors and the ever-shrinking feature sizes of MOSFETs hold a lot of promise, new design techniques need to be devised to deal with the realities of these technologies, such as low breakdown voltages, lossy substrates, low-Q passives, long interconnect parasitics, and high-frequency coupling issues. As an example of complete system integration in silicon, this paper presents the first fully integrated 24-GHz eight-element phased array receiver in 0.18-ÎĽm silicon-germanium and the first fully integrated 24-GHz four-element phased array transmitter with integrated power amplifiers in 0.18-ÎĽm CMOS. The transmitter and receiver are capable of beam forming and can be used for communication, ranging, positioning, and sensing applications

    A 1.2 V and 69 mW 60 GHz Multi-channel Tunable CMOS Receiver Design

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    A multi-channel receiver operating between 56 GHz and 70 GHz for coverage of different 60 GHz bands worldwide is implemented with a 90 nm Complementary Metal-Oxide Semiconductor (CMOS) process. The receiver containing an LNA, a frequency down-conversion mixer and a variable gain amplifier incorporating a band-pass filter is designed and implemented. This integrated receiver is tested at four channels of centre frequencies 58.3 GHz, 60.5 GHz, 62.6 GHz and 64.8 GHz, employing a frequency plan of an 8 GHz-intermediate frequency (IF). The achieved conversion gain by coarse gain control is between 4.8 dB–54.9 dB. The millimeter-wave receiver circuit is biased with a 1.2V supply voltage. The measured power consumption is 69 mW

    A fully integrated 24-GHz phased-array transmitter in CMOS

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    This paper presents the first fully integrated 24-GHz phased-array transmitter designed using 0.18-/spl mu/m CMOS transistors. The four-element array includes four on-chip CMOS power amplifiers, with outputs matched to 50 /spl Omega/, that are each capable of generating up to 14.5 dBm of output power at 24 GHz. The heterodyne transmitter has a two-step quadrature up-conversion architecture with local oscillator (LO) frequencies of 4.8 and 19.2 GHz, which are generated by an on-chip frequency synthesizer. Four-bit LO path phase shifting is implemented in each element at 19.2 GHz, and the transmitter achieves a peak-to-null ratio of 23 dB with raw beam-steering resolution of 7/spl deg/ for radiation normal to the array. The transmitter can support data rates of 500 Mb/s on each channel (with BPSK modulation) and occupies 6.8 mm /spl times/ 2.1 mm of die area

    Design of a CMOS RF Front End Receiver in 0.18ÎĽm Technology

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    An RF front end receiver system refers to the analog down conversion stages of the wireless communication system. The Digital base-band signals cannot be transmitted directly through wireless channels due to the properties of electromagnetic waves. The baseband signals need to be converted to analog through a digital-to-analog converter (DAC), up converted to higher frequency using an up conversion mixer and then transmitted through the channel. The received signals are down converted to base band frequency and then converted to digital again using the analog to digital converter (ADC). The processes which the analog signal undergoes at the RF front end include amplification, mixing and filtering. The RF Front End receiver developed in this thesis makes use of a differential low noise amplifier (LNA) with center frequency at 1.75GHz. The incoming RF signal undergoes amplification by the LNA and is down converted by a Gilbert double balanced mixer to a first Intermediate frequency (IF) of 250 MHz A second Gilbert Double Balanced Mixer down converts to a low second IF of 50 MHz The local oscillator signal for the mixer is generated using a voltage controlled ring oscillator (VCO). The entire front end of the receiver was created in Cadence virtuoso schematic editor using CMOS 0.18ÎĽm technology. The total power consumed by the RF Front End Receiver is 113.36 mW

    Design of Integrated Mixer for 5G Radio Transceiver

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    The increased demand of high data rate, low latency and wider bandwidth is pushing the wireless communication towards higher frequencies. 3GPP (third generation partnership project) allocated NR (new radio) FR2 (frequency range 2) n257 (26.5 - 29.5 GHz) and n258 (24.25 - 27.5 GHz) bands for high-speed communication. It is challenging to achieve high linearity at higher frequencies with low supply voltage and smaller size devices. This thesis presents design, implementation and simulation results of integrated downconversion mixer for modular 5G radio transceiver. The first stage downconversion mixer, implemented in GF FDSOI 22 nm process will be used in super-heterodyne double downconversion transceiver, operates at 28 GHz input frequency and provides 6-7 GHz intermediate frequency (IF). The pre-layout and post-layout simulation results of double-balanced mixer topologies optimized for high linearity are compared in terms of conversion gain (CG), input third-order intercept point (IIP3), double sideband (DSB) noise figure (NF), LO-to-IF leakage,and dc power consumption. The mixer topologies, including Gilbert cell and variants of Gilbert cell with resistive and inductive degeneration, and mixer with transformer input, show trade-off between conversion gain, linearity, dc power consumption, and area. Under 0.8-V supply voltage, the transformer input mixer achieves highest IIP3 of +16.34 dBm while dc power consumption including LO buffer is 5.7 mW and NFdsb is 13.7 dB

    Design of a low-voltage CMOS RF receiver for energy harvesting sensor node

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    In this thesis a CMOS low-power and low-voltage RF receiver front-end is presented. The main objective is to design this RF receiver so that it can be powered by a piezoelectric energy harvesting power source, included in a Wireless Sensor Node application. For this type of applications the major requirements are: the low-power and low-voltage operation, the reduced area and cost and the simplicity of the architecture. The system key blocks are the LNA and the mixer, which are studied and optimized with greater detail, achieving a good linearity, a wideband operation and a reduced introduction of noise. A wideband balun LNA with noise and distortion cancelling is designed to work at a 0.6 V supply voltage, in conjunction with a double-balanced passive mixer and subsequent TIA block. The passive mixer operates in current mode, allowing a minimal introduction of voltage noise and a good linearity. The receiver analog front-end has a total voltage conversion gain of 31.5 dB, a 0.1 - 4.3 GHz bandwidth, an IIP3 value of -1.35 dBm, and a noise figure lower than 9 dB. The total power consumption is 1.9 mW and the die area is 305x134.5 m2, using a standard 130 nm CMOS technology

    Design and characterization of downconversion mixers and the on-chip calibration techniques for monolithic direct conversion radio receivers

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    This thesis consists of eight publications and an overview of the research topic, which is also a summary of the work. The research described in this thesis is focused on the design of downconversion mixers and direct conversion radio receivers for UTRA/FDD WCDMA and GSM standards. The main interest of the work is in the 1-3 GHz frequency range and in the Silicon and Silicon-Germanium BiCMOS technologies. The RF front-end, and especially the mixer, limits the performance of direct conversion architecture. The most stringent problems are involved in the second-order distortion in mixers to which special attention has been given. The work introduces calibration techniques to overcome these problems. Some design considerations for front-end radio receivers are also given through a mixer-centric approach. The work summarizes the design of several downconversion mixers. Three of the implemented mixers are integrated as the downconversion stages of larger direct conversion receiver chips. One is realized together with the LNA as an RF front-end. Also, some stand-alone structures have been characterized. Two of the mixers that are integrated together with whole analog receivers include calibration structures to improve the second-order intermodulation rejection. A theoretical mismatch analysis of the second-order distortion in the mixers is also presented in this thesis. It gives a comprehensive illustration of the second-order distortion in mixers. It also gives the relationships between the dc-offsets and high IIP2. In addition, circuit and layout techniques to improve the LO-to-RF isolation are discussed. The presented work provides insight into how the mixer immunity against the second-order distortion can be improved. The implemented calibration structures show promising performance. On the basis of these results, several methods of detecting the distortion on-chip and the possibilities of integrating the automatic on-chip calibration procedures to produce a repeatable and well-predictable receiver IIP2 are presented.reviewe

    Design and Simulate Radio Frequency (RF) CMOS Mixer Circuit

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    Radio frequency design has been one of the principal research areas in the· recent past. Much of work has been done in integrating data with wireless communication. Since a decade ago, the frequencies for such communication have been in free bands available in the low frequency spectrum like 900 MHz and lower. With rapid improvement in the technology of microelectronic nowadays, these frequency spectrums are improved to be within the range of ultra band frequencies of GHz. These emergences of several RF Wireless Communication standards of communication have demanded availability of low cost analogue blocks for use in transceiver. Despite rigorous research undergoing, it has been difficult to meet the design specification by low cost technologies like CMOS. In this project, the presented mixer down converts Radio Frequency (RF) of 1.8 GHz to 200 MHz which typifies specifications for a GSM 1800 receiver with Voltage Conversion Gain (VCG) of 7.703 dB, IIP3 of 10.916 dBm and Noise Figure (NF) of 11.094 dB with current utilization of 6 rnA. This hi.gh conversion gain and low noise figure mixer is achieved by utilizing Differential Gilbert Mixer Cell. The mixer was simulated in analogue environment of Spectra Cadence Schematic
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