190 research outputs found

    2.4-GHz single-ended input low-power low-voltage active front-end for zigbee applications in 90 nm CMOS

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    Congreso celebrado en Linkoping (Suecia) del 29 al 31 de Agosto del 2011.A 2.4-GHz CMOS single ended-input differential-output front-end built with a common source low noise amplifier (CS-LNA) and a switched transconductor mixer (SW-MIX) is presented. The circuit is designed and optimized to work in a ZigBee receiver. Since this is a low power consumption standard, a single-ended LNA is preferred over a fully-differential topology because it leads to lower cost in area and power consumption. Also, moderate and weak inversions regions were selected for the operation of the principal transistors. The front-end prototype has been implemented in a 90 nm RF process and occupies a chip area of 0.74 mm2 including on-chip inductors. Very competitive results are observed: a maximum conversion gain (CG) of 30 dB, a DSB noise figure of 7.5 dB, a maximum IIP3 of -12.8 dBm and IIP2 of 14.4 dBm while it consumes 4.7 mW from a 1.2 V supply.This work has been financed in part by FEDER funds through the SR2 project (Catrene2A105SR2 under the Avanza+ Spanish program TSI-020400-2010-55) and the Andalusian Government project P09-TIC-5386, and by the Spanish MAE-AECID grants program.Peer Reviewe

    A 0.1–5.0 GHz flexible SDR receiver with digitally assisted calibration in 65 nm CMOS

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    © 2017 Elsevier Ltd. All rights reserved.A 0.1–5.0 GHz flexible software-defined radio (SDR) receiver with digitally assisted calibration is presented, employing a zero-IF/low-IF reconfigurable architecture for both wideband and narrowband applications. The receiver composes of a main-path based on a current-mode mixer for low noise, a high linearity sub-path based on a voltage-mode passive mixer for out-of-band rejection, and a harmonic rejection (HR) path with vector gain calibration. A dual feedback LNA with “8” shape nested inductor structure, a cascode inverter-based TCA with miller feedback compensation, and a class-AB full differential Op-Amp with Miller feed-forward compensation and QFG technique are proposed. Digitally assisted calibration methods for HR, IIP2 and image rejection (IR) are presented to maintain high performance over PVT variations. The presented receiver is implemented in 65 nm CMOS with 5.4 mm2 core area, consuming 9.6–47.4 mA current under 1.2 V supply. The receiver main path is measured with +5 dB m/+5dBm IB-IIP3/OB-IIP3 and +61dBm IIP2. The sub-path achieves +10 dB m/+18dBm IB-IIP3/OB-IIP3 and +62dBm IIP2, as well as 10 dB RF filtering rejection at 10 MHz offset. The HR-path reaches +13 dB m/+14dBm IB-IIP3/OB-IIP3 and 62/66 dB 3rd/5th-order harmonic rejection with 30–40 dB improvement by the calibration. The measured sensitivity satisfies the requirements of DVB-H, LTE, 802.11 g, and ZigBee.Peer reviewedFinal Accepted Versio

    Low-power CMOS front-ends for wireless personal area networks

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    The potential of implementing subthreshold radio frequency circuits in deep sub-micron CMOS technology was investigated for developing low-power front-ends for wireless personal area network (WPAN) applications. It was found that the higher transconductance to bias current ratio in weak inversion could be exploited in developing low-power wireless front-ends, if circuit techniques are employed to mitigate the higher device noise in subthreshold region. The first fully integrated subthreshold low noise amplifier was demonstrated in the GHz frequency range requiring only 260 μW of power consumption. Novel subthreshold variable gain stages and down-conversion mixers were developed. A 2.4 GHz receiver, consuming 540 μW of power, was implemented using a new subthreshold mixer by replacing the conventional active low noise amplifier by a series-resonant passive network that provides both input matching and voltage amplification. The first fully monolithic subthreshold CMOS receiver was also implemented with integrated subthreshold quadrature LO (Local Oscillator) chain for 2.4 GHz WPAN applications. Subthreshold operation, passive voltage amplification, and various low-power circuit techniques such as current reuse, stacking, and differential cross coupling were combined to lower the total power consumption to 2.6 mW. Extremely compact resistive feedback CMOS low noise amplifiers were presented as a cost-effective alternative to narrow band LNAs using high-Q inductors. Techniques to improve linearity and reduce power consumption were presented. The combination of high linearity, low noise figure, high broadband gain, extremely small die area and low power consumption made the proposed LNA architecture a compelling choice for many wireless applications.Ph.D.Committee Chair: Laskar, Joy; Committee Member: Chakraborty, Sudipto; Committee Member: Chang, Jae Joon; Committee Member: Divan, Deepakraj; Committee Member: Kornegay, Kevin; Committee Member: Tentzeris, Emmanoui

    Receiver Front-Ends in CMOS with Ultra-Low Power Consumption

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    Historically, research on radio communication has focused on improving range and data rate. In the last decade, however, there has been an increasing demand for low power and low cost radios that can provide connectivity with small devices around us. They should be able to offer basic connectivity with a power consumption low enough to function extended periods of time on a single battery charge, or even energy scavenged from the surroundings. This work is focused on the design of ultra-low power receiver front-ends intended for a receiver operating in the 2.4GHz ISM band, having an active power consumption of 1mW and chip area of 1mm². Low power consumption and small size make it hard to achieve good sensitivity and tolerance to interference. This thesis starts with an introduction to the overall receiver specifications, low power radio and radio standards, front-end and LO generation architectures and building blocks, followed by the four included papers. Paper I demonstrates an inductorless front-end operating at 915MHz, including a frequency divider for quadrature LO generation. An LO generator operating at 2.4GHz is shown in Paper II, enabling a front-end operating above 2GHz. Papers III and IV contain circuits with combined front-end and LO generator operating at or above the full 2.45GHz target frequency. They use VCO and frequency divider topologies that offer efficient operation and low quadrature error. An efficient passive-mixer design with improved suppression of interference, enables an LNA-less design in Paper IV capable of operating without a SAW-filter

    Designing of Low Power RF-Receiver Front-end with CMOS Technology

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    This thesis studies how to design ultra low power radio-receiver front-end circuit consisting of a low-noise CMOS amplifier and mixer for low power Bluetooth applications. This system is designed in 65-nm CMOS technology with the voltage source of 1.2 V, and it operates at 2.4 GHz. This research project includes the design of radio frequency integrated circuit with CMOS technology using CAD software for circuit design, layout design, pre and post-layout simulations. Firstly, brief study about both Low noise amplifier (LNA) and mixer has been done, and then the design structure such as, input matching network of LNA, noise of system, gain and linearity have been discussed. Later, next section reports simulation results of LNA, mixer and eventually their combination. Furthermore, the effect of packaging and non-ideal on-chip circuit performance has been considered and shown in comparison tables for more clarity. Finally, after the layout design, the obtained results of both post-layout and pre-layout simulations are compared and shown the stability of the design with parasitics consideration

    HIGH LINEARITY UNIVERSAL LNA DESIGNS FOR NEXT GENERATION WIRELESS APPLICATIONS

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    Design of the next generation (4G) systems is one of the most active and important area of research and development in wireless communications. The 2G and 3G technologies will still co-exist with the 4G for a certain period of time. Other applications such as wireless LAN (Local Area Network) and RFID are also widely used. As a result, there emerges a trend towards integrating multiple wireless functionalities into a single mobile device. Low noise amplifier (LNA), the most critical component of the receiver front-end, determines the sensitivity and noise figure of the receiver and is indispensable for the complete system. To satisfy the need for higher performance and diversity of wireless communication systems, three LNAs with different structures and techniques are proposed in the thesis based on the 4G applications. The first LNA is designed and optimized specifically for LTE applications, which could be easily added to the existing system to support different standards. In this cascode LNA, the nonlinearity coming from the common source (CS) and common gate (CG) stages are analyzed in detail, and a novel linear structure is proposed to enhance the linearity in a relatively wide bandwidth. The LNA has a bandwidth of 900MHz with the linearity of greater than 7.5dBm at the central frequency of 1.2GHz. Testing results show that the proposed structure effectively increases and maintains linearity of the LNA in a wide bandwidth. However, a broadband LNA that covers multiple frequency ranges appears more attractive due to system simplicity and low cost. The second design, a wideband LNA, is proposed to cover multiple wireless standards, such as LTE, RFID, GSM, and CDMA. A novel input-matching network is proposed to relax the tradeoff among noise figure and bandwidth. A high gain (>10dB) in a wide frequency range (1-3GHz) and a minimum NF of 2.5dB are achieved. The LNA consumes only 7mW on a 1.2V supply. The first and second LNAs are designed mainly for the LTE standard because it is the most widely used standard in the 4G communication systems. However, WiMAX, another 4G standard, is also being widely used in many applications. The third design targets on covering both the LTE and the WiMAX. An improved noise cancelling technique with gain enhancing structure is proposed in this design and the bandwidth is enlarged to 8GHz. In this frequency range, a maximum power gain of 14.5dB and a NF of 2.6-4.3dB are achieved. The core area of this LNA is 0.46x0.67mm2 and it consumes 17mW from a 1.2V supply. The three designs in the thesis work are proposed for the multi-standard applications based on the realization of the 4G technologies. The performance tradeoff among noise, linearity, and broadband impedance matching are explored and three new techniques are proposed for the tradeoff relaxation. The measurement results indicate the techniques effectively extend the bandwidth and suppress the increase of the NF and nonlinearity at high frequencies. The three proposed structures can be easily applied to the wideband and multi-standard LNA design

    Design of zigbee transmitter for IEEE 802.15.4 standrad

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    ZigBee is a standard defines a set of communication protocols for low-data-rate short-range wireless networking. ZigBee-based wireless devices operate in 868 MHz, 915 MHz, and 2.4 GHz frequency bands. The maximum data rate is 250 K bits per second. ZigBee is mainly for battery-powered applications where low data rate, low cost, and long battery life are main requirements. This thesis explores low power RFIC design for various blocks in Zigbee Transmitter. Zigbee RFTransmitter Comprises of Low Pass Filter, Variable Gain Amplifier, Up conversion Mixer and Power Amplifier. The proposed VGA is characterized by a wide range of gain variation The single-stage VGA is designed in UMC 0.18-u m CMOS technology and shows the maximum gain variation of 62 dB. The VGA dissipates 630 uA from 1.8-V supply while occupying (250 μm x 167.3 μm) of chip area. A low-voltage low-power and high linearity up-conversion mixer, designed in UMC 0.18-um RFCMOS technology is proposed to realize the transmitter front-end in the frequency band of 2.45 GHz. The proposed mixer can convert a 5 MHz intermediate frequency (IF) signals to a 2.45GHz RF signals, with a local oscillator at 2.45GHz. Simulation results demonstrate that at 2.45GHz, the circuit provides -11.30dB of conversion gain and the input-referred third-order intercept point (IIP3) of 35.16 dBm, output-referred third order intercept point(OIP3) of 12.88 dBm while drawing only 10mA for the mixer core under a supply voltage of 1.8 V. A low power Differential class A power amplifier is designed in the UMC 0.18um RFCMOS technology. The class A power amplifier provides 0 dBm output power with a power-added efficiency (PAE) of 22% and Power Gain of 10dB with 1.8V supply voltage. The dc power consumption is only 4.5mW. And all these blocks were integrated and simulated using Cadence© SpectreRF simulator in UMC-0.18um Mixed Signal CMOS RF models for the best simulation results

    Multi-gigabit CMOS analog-to-digital converter and mixed-signal demodulator for low-power millimeter-wave communication systems

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    The objective of the research is to develop high-speed ADCs and mixed-signal demodulator for multi-gigabit communication systems using millimeter-wave frequency bands in standard CMOS technology. With rapid advancements in semiconductor technologies, mobile communication devices have become more versatile, portable, and inexpensive over the last few decades. However, plagued by the short lifetime of batteries, low power consumption has become an extremely important specification in developing mobile communication devices. The ever-expanding demand of consumers to access and share information ubiquitously at faster speeds requires higher throughputs, increased signal-processing functionalities at lower power and lower costs. In today’s technology, high-speed signal processing and data converters are incorporated in almost all modern multi-gigabit communication systems. They are key enabling technologies for scalable digital design and implementation of baseband signal processors. Ultimately, the merits of a high performance mixed-signal receiver, such as data rate, sensitivity, signal dynamic range, bit-error rate, and power consumption, are directly related to the quality of the embedded ADCs. Therefore, this dissertation focuses on the analysis and design of high-speed ADCs and a novel broadband mixed-signal demodulator with a fully-integrated DSP composed of low-cost CMOS circuitry. The proposed system features a novel dual-mode solution to demodulate multi-gigabit BPSK and ASK signals. This approach reduces the resolution requirement of high-speed ADCs, while dramatically reducing its power consumption for multi-gigabit wireless communication systems.PhDGee-Kung Chang - Committee Chair; Chang-Ho Lee - Committee Member; Geoffrey Ye Li - Committee Member; Paul A. Kohl - Committee Member; Shyh-Chiang Shen - Committee Membe

    Energy-Efficient Wireless Circuits and Systems for Internet of Things

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    As the demand of ultra-low power (ULP) systems for internet of thing (IoT) applications has been increasing, large efforts on evolving a new computing class is actively ongoing. The evolution of the new computing class, however, faced challenges due to hard constraints on the RF systems. Significant efforts on reducing power of power-hungry wireless radios have been done. The ULP radios, however, are mostly not standard compliant which poses a challenge to wide spread adoption. Being compliant with the WiFi network protocol can maximize an ULP radio’s potential of utilization, however, this standard demands excessive power consumption of over 10mW, that is hardly compatible with in ULP systems even with heavy duty-cycling. Also, lots of efforts to minimize off-chip components in ULP IoT device have been done, however, still not enough for practical usage without a clean external reference, therefore, this limits scaling on cost and form-factor of the new computer class of IoT applications. This research is motivated by those challenges on the RF systems, and each work focuses on radio designs for IoT applications in various aspects. First, the research covers several endeavors for relieving energy constraints on RF systems by utilizing existing network protocols that eventually meets both low-active power, and widespread adoption. This includes novel approaches on 802.11 communication with articulate iterations on low-power RF systems. The research presents three prototypes as power-efficient WiFi wake-up receivers, which bridges the gap between industry standard radios and ULP IoT radios. The proposed WiFi wake-up receivers operate with low power consumption and remain compatible with the WiFi protocol by using back-channel communication. Back-channel communication embeds a signal into a WiFi compliant transmission changing the firmware in the access point, or more specifically just the data in the payload of the WiFi packet. With a specific sequence of data in the packet, the transmitter can output a signal that mimics a modulation that is more conducive for ULP receivers, such as OOK and FSK. In this work, low power mixer-first receivers, and the first fully integrated ultra-low voltage receiver are presented, that are compatible with WiFi through back-channel communication. Another main contribution of this work is in relieving the integration challenge of IoT devices by removing the need for external, or off-chip crystals and antennas. This enables a small form-factor on the order of mm3-scale, useful for medical research and ubiquitous sensing applications. A crystal-less small form factor fully integrated 60GHz transceiver with on-chip 12-channel frequency reference, and good peak gain dual-mode on-chip antenna is presented.PHDElectrical and Computer EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/162975/1/jaeim_1.pd

    Energy-Aware Low-Power CMOS LNA with Process-Variations Management

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    A reconfigurable low-noise amplifier (LNA) with digitally controllable gain and power consumption is presented.This architecture allows increasing power consumption only when required, that is, to improve LNA’s radiofrequency performance at extreme communication-channel conditions and/or to counteract the effect of process, voltage, and temperature variations.The proposed design leads to significant power saving when a relaxed operation is acceptable. The LNA is implemented in a 130nm 1.2V CMOS technology for a 2.4GHz IEEE-802.15.4 application. Simulated LNAperformance (taking into account theworst cases under process variations) is comparable to recently published worksCAPES-Brazil 176/12Ministerio de Asuntos Exteriores y Cooperación D/024124/09Junta de Andalucía P09-TIC- 5386Ministerio de Economía y Competitividad TEC2011-2830
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