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Chaotic Behavior in Receiver Front-End Limiters
Fran ois Caudron;Achour Ouslimani;Rene Vezinet;Abed-elhak Kasbari
PIER Letters , 2011, DOI: 10.2528/PIERL11020305
Abstract: A delay nonlinear differential equation is proposed to investigate the condition of the microwave chaotic behavior existing between the antenna and the front-end protection circuit of a receiver such as the radar front-end limiter circuit. This investigation concerns the case of intentional or unintentional signals applied to the antenna outside of its bandwidth. Bifurcation diagrams show that the chaotic behavior appears for antenna impedance up to 10 Ω and for amplitudes greater than 1.2 V. Electrical simulation results agree well with theoretical ones.
A 48μW Analog Front End Circuit Design for an Ultrasonic Receiver 0.18μm CMOS
Haridas Kuruveettil,Simon Sheung Yan Ng,Minkyu Je
International Journal of Information and Electronics Engineering , 2013, DOI: 10.7763/ijiee.2013.v3.253
Abstract: Ultrasonic transducer based sensor systems are widely used in wearable biomedical applications for indoor location sensing, tracking and other zonal compliance purposes. A system used for zonal compliance typically made up with a zonal transceiver device and a battery powered wearable device with the associated control logic at each interface. Being battery powered, the design of analog interface circuit to the wearable device is significant to overall performance of the system. In this paper, we present a fully integrated Analog Front End (AFE) interface circuit for the ultrasonic receiver designed and fabricated in 0.18μm CMOS. Measurement results shows that the single chip receiver operating at a centre frequency of 40 KHz reduce the power consumption to less than half over the discrete version.
Design and Simulation of a Fully Digitized GNSS Receiver Front-End  [PDF]
Yuan Yu,Qing Chang,Yuan Chen
Discrete Dynamics in Nature and Society , 2011, DOI: 10.1155/2011/329535
Abstract: In the near future, RF front-ends of GNSS receivers may become very complicated when multifrequency signals are available from at least four global navigation systems. Based on the direct RF sampling technique, fully digitized receiver front-ends may solve the problem. In this paper, a direct digitization RF front-end scheme is presented. At first, a simplified sampling rate selection method is adopted to determine the optimal value. Then, the entire spectrum of GNSS signal is directly digitized through RF sampling at a very fast sampling rate. After that, the decimation and filtering network is designed to lower the sampling rate efficiently. It also realizes the digital downconversion of the signal of interest and the separation of narrow band signals from different navigation systems. The scheme can be flexibly implemented in software. Its effectiveness is proved through the experiment using simulated and true signals. 1. Introduction With the development of global navigation satellite system (GNSS) including GPS, GLONASS, GALILEO, and COMPASS, multi-constellation signals will be available in the future. These signals mainly concentrate in 1164~1300?MHz and 1559~1610?MHz (referred as “Band I” and “Band II” below). In order to receive all of the GNSS signals, conventional RF front-end may not fit for future multisystem receivers. From the theory of software radio, A/D needs to be set as close to the antenna as possible, thus a single hardware configuration could operate as multiple receivers simply by changing the software programming [1]. Based on such idea, the direct RF sampling offers several advantages for GNSS RF front-end design. First, it reduces the parts count and eliminates the need to design and fabricate a mixing chip with a specially tailored frequency plan. Second, it simplifies the design of new receivers for the new signals that will become available as GPS gets modernized and as Galileo comes on line. Third, it is possible to make a single RF front-end for multiple frequency bands. This approach to multifrequency GNSS receiver front-end design eliminates the need for multiple front-ends, which reduces the parts count and eliminates some potential sources of inter channel line bias. Therefore, the digitized RF front-end is becoming a hot research area. Although software radio is not a novel concept, most studies on direct RF sampling nowadays are still conducted in labs. Brown and Wolt [2] are the first to report on the use of direct RF sampling for the design of GPS receiver front-ends. They concentrated on a system that used a very
Calibration method for direct conversion receiver front-ends  [PDF]
R. Müller,H.-J. Jentschel
Advances in Radio Science : Kleinheubacher Berichte , 2008,
Abstract: Technology induced process tolerances in analog circuits cause device characteristics different from specification. For direct conversion receiver front-ends a system level calibration method is presented. The malfunctions of the devices are compensated by tuning dominant circuit parameters. Thereto optimization techniques are applied which use measurement values and special evaluation functions.
Man-Made Noise Evaluation for Cryogenic Receiver Front-End  [cached]
Shoichi Narahashi,Kei Satoh,Yasunori Suzuki,Tetsuya Mimura
Journal of Communications , 2008, DOI: 10.4304/jcm.3.5.54-61
Abstract: This paper presents measured results of manmade noise impact on an cryogenic receiver front-end (CRFE) in urban and suburban areas in the 2-GHz band with amplitude probability distribution (APD). The CRFE comprises a high-temperature superconducting filter, cryogenically-cooled low-noise amplifier, and highly-reliable cryostat. The CRFE is expected to be an effective and practical approach to attain efficient frequency utilization and to improve the sensitivity of mobile base station receivers. It is important to measure the characteristics of man-made noise in typical cellular base station antenna environments and confirm their impact on the CRFE reception with APD because if man-made noise has a stronger effect than thermal noise, the CRFE would fail to offer any improvement in sensitivity. The measured results suggest that the contribution of man-made noise in the 2-GHz band can be ignored as far as Wideband Code Division Multiple Access (W-CDMA) system is concerned. The manmade noise is also measured in the VHF-band for comparison with the 2-GHz band environment.
Design of RF Front End Mixer Circuit for an Ultra Wide Band Receiver
Mr. Jaikaran Singh,Pradip Kumar Vishwakarma
International Journal of Engineering Innovations and Research , 2012,
Abstract: Ultra-Wideband (UWB) technologies are widely accepted as the center piece of ubiquitous wireless interconnects for next generation Wireless Personal Area Networks (WPAN). It finds potential exciting applications in high-connectivity and high interoperability multimedia consumer products within personal operating space, such as wireless home video distributions systems, and high-speed, high-mobility cable replacement solutions, such as Wireless Universal Serial Bus (W-USB) and wireless IEEE-1394 Fire wire. Many active academic and industrial works have been dedicated to the implementation of UWB transceivers, however, a monolithic UWB radio expanding across full 3.1–10.6 GHz UWB spectrum is yet to be accomplished. Targeting Multi-Band Orthogonal Frequency Division Multiplexing (MB-OFDM) UWB, one of the two major competing industrial UWB standards, this paper focuses on system and circuit co-design of a fully integrated CMOS direct-conversion Mixer with emphasis on architectural issue, and circuit topologies of its RF front-end. In this paper, a CMOS Ultra-wideband mixer was designed and simulated. Specific architecture has been selected Mixer implementation of an Ultra-wideband communication system. The basic architecture of the Mixer maintains a gain of 15dB over the band of 3.1-10.2GHz. The Mixer achieved a Noise figure ranging from 9-9.5dB over the same band of operation
Dedicated front-end and readout electronics developments for real time 3D directional detection of dark matter with MIMAC  [PDF]
O. Bourrion,G. Bosson,C. Grignon,J. P. Richer,O. Guillaudin,F. Mayet,J. Billard,D. Santos
Physics , 2011, DOI: 10.1051/eas/1253016
Abstract: A complete dedicated electronics, from front-end to back-end, was developed to instrument a MIMAC prototype. A front end ASIC able to monitor 64 strips of pixels and to provide their individual "Time Over Threshold" information has been designed. An associated acquisition electronics and a real time track reconstruction software have been developed to monitor a 512 channel prototype. This auto-triggered electronic uses embedded processing to reduce the data transfer to its useful part only, i.e. decoded coordinates of hit tracks and corresponding energy measurements. The electronic designs, acquisition software and the results obtained are presented.
A 0.8–6?GHz Wideband Receiver Front-End for Software-Defined Radio  [PDF]
Kuan-Ting Lin,Tao Wang,Shey-Shi Lu
Active and Passive Electronic Components , 2013, DOI: 10.1155/2013/725075
Abstract: A wideband (0.8–6?GHz) receiver front-end (RFE) utilizing a shunt resistive feedback low-noise amplifier (LNA) and a micromixer is realized in 90?nm CMOS technology for software-defined radio (SDR) applications. With the shunt resistive feedback and series inductive peaking, the proposed LNA is able to achieve a wideband frequency response in input matching, power gain and noise figure (NF). A micromixer down converts the radio signal and performs single-to-differential transition. Measurements show the conversion gain higher than 17?dB and input matching (S11) better than ?7.3?dB from 0.8 to 6?GHz. The IIP3 ranges from ?7 to ?10?dBm, and the NF from 4.5 to 5.9?dB. This wideband receiver occupies 0.48?mm2 and consumes 13?mW. 1. Introduction Software-defined radio was designed to process any signal within a certain bandwidth [1]. For an SDR in 0.8–6?GHz region, it includes signals of GSM, 3?G, WLAN, Bluetooth, WiMAX, and GPS applications. Such an idea can be realized by using an ultra-high speed ADC for direct sampling, but the power consumption of the high speed ADC is too large to accept. Relatively, a SDR receiver that down-converts signals before ADC appears to be a more practical approach. The intuitive SDR receiver topology is to connect front-ends of different standards in parallel as shown in Figure 1(a); nevertheless, the chip size of such topology would be too large. A wideband radio [2–6] and a tunable-band radio [7–9] (see Figure 1(b)) are good candidates for this purpose. The most challenging problem is how to design an LNA and a mixer that meet all the requirements in such a wideband from 800?MHz to 6?GHz. Figure 1: (a) Multiband receiver architecture. (b) Wideband or tunable-band receiver architecture. A wideband RFE can be implemented by several circuit structures. Conventional common-gate LNAs feature wide input matching and gain bandwidths [4]. However, the multiple stages required by such circuits for gain and noise flatness can be power hungry. A shunt-shunt feedback LNA followed by a passive mixer [2, 5, 6] can be an option, but its gain degrades at high frequency due to the large capacitance at its input and output stages. Besides, the trade-off between noise figure and bandwidth remains an issue. Tunable-band receivers switching its frequency with tunable passive devices [7–9] would be promising, except that the size of passive devices is too costly to accept. Designs of mixers can be also challenging for SDR. Passive mixers are widely used for frequency down-conversion. Very large power is needed for LO input to drive these
Fully On-Chip Integrated Photodetector Front-End Dedicated to Real-Time Portable Optical Brain Imaging  [PDF]
Ehsan Kamrani, Frederic Lesage, Mohamad Sawan
Optics and Photonics Journal (OPJ) , 2012, DOI: 10.4236/opj.2012.24037

Optical brain imaging using functional near infra-red spectroscopy (fNIRS) offers a portable and noninvasive tool for monitoring of blood oxygenation. In this paper we have introduced a new miniaturized photodetector front-end on achip to be applied in a portable fNIRS system. It includes silicon avalanche photodiodes (SiAPD), Transimpedance amplifier (TIA) front-end and Quench-Reset circuitry to operate in both linear and Geiger modes. So it can be applied for both continuous-wave fNIRS (CW-fNIRS) and also single-photon counting. Proposed SiAPD exhibits high-avalanche gain (>100), low-breakdown voltage (<12 V) and high photon detection efficiency accompanying with low dark count rates. The proposed TIA front-end offer a low power consumption (<1 mW), high-transimpedance gain (up to 250 MV/A), tunable bandwidth (1 kHz - 1 GHz) and very low input and output noise (~few fA/√Hz and few μV/√Hz). The Geiger-mode photon counting front-end also exhibits a controllable hold-off and rest time with an ultra fast quench-reset time (few ns). This integrated system has been implemented using submicron (0.35 μm) standard CMOS technology.

A Compact X-Band Receiver Front-End Module Based on Low Temperature Co-Fired Ceramic Technology
Zhigang Wang;Ping Li;Rui-Min Xu;Weigan Lin
PIER , 2009, DOI: 10.2528/PIER09040701
Abstract: This letter presents a compact low temperature co-fired ceramic (LTCC) receiver front-end module integrating 9 building blocks. The receiver is a twicefrequency- conversion front-end module with image injection, works at X-band, consists of an X-band embedded image injection band-pass filter (BPF), an L-band multilayer image injection quasi-ellipitc BPF, two monolithic microwave integrated circuit (MMIC) low noise amplifiers (LNAs), two intermediate frequency (IF) amplifiers, two mixers, a IF BPF, and some lumped passive components. All MMICs are mounted into pre-making cavities in the three layers LTCC substrate of the top surface, and the interconnection between MMICs and surface microstrip-line is established by bond wires. A multilayer five-pole Chebyshev interdigital BPF is developed as the first image injection filter, and a four-pole quasi-elliptic BPF composed of stepped-impedance hairpin resonator and miniaturized hairpin resonators that can be coupled through the apertures on the common ground plane is proposed for as the second image injection filter. The developed X-band receiver front-end module is fabricated using twenty layers LTCC dielectric substrate, which has a compact size of 30 × 20 × 20 mm (including the metal cavity). The measured receiver gain and noise figure are more than 32 dB and less than 4 dB, respectively. The first and second image injection is better than 28 dB and 40 dB, respectively.
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