Over the past two decades we have witnessed the increasing popularity of the internet of things. The vision of billions of connected objects, able to interact with their environment, is the key ...driver directing the development of future communication devices. Today, power consumption as well as the cost and size of radios remain some of the key obstacles towards fulfilling this vision. Ultra-Low Power FM-UWB Transceivers for IoT presents the latest developments in the field of low power wireless communication. It promotes the FM-UWB modulation scheme as a candidate for short range communication in different IoT scenarios. The FM-UWB has the potential to provide exactly what is missing today. This spread spectrum technique enables significant reduction in transceiver complexity, making it smaller, cheaper and more energy efficient than most alternative options.The book provides an overview of both circuit-level and architectural techniques used in low power radio design, with a comprehensive study of state-of-the-art examples. It summarizes key theoretical aspects of FM-UWB with a glimpse at potential future research directions. Finally, it gives an insight into a full FM-UWB transceiver design, from system level specifications down to transistor level design, demonstrating the modern power reduction circuit techniques.Ultra-Low Power FM-UWB Transceivers for IoT is a perfect text and reference for engineers working in RF IC design and wireless communication, as well as academic staff and graduate students engaged in low power communication systems research.
A wireless sensor network consists of many energy-autonomous microsensors distributed throughout an area of interest. Each node monitors its local environment, locally processing and storing the ...collected data so that other nodes can use it. To optimize power consumption, the Swiss Center for Electronics and Microtechnology has developed WiseNET, an ultralow-power platform for the implementation of wireless sensor networks that achieves low-power operation through a careful codesign approach. The WiseNET platform uses a codesign approach that combines a dedicated duty-cycled radio with WiseMAC, a low-power media access control protocol, and a complex system-on-chip sensor node to exploit the intimate relationship between MAC-layer performance and radio transceiver parameters. The WiseNET solution consumes about 100 times less power than comparable solutions.
This paper presents a 4-GHz FM ultra-wideband (UWB) transceiver designed for the Internet of Things and body area network applications. Robustness to interferers and low power spectral density allow ...FM-UWB to coexist with narrowband radios, while large signal bandwidth strongly relaxes constraints on the frequency synthesis blocks enabling the full integration of the radio at low power. The transceiver, integrated with a 65-nm standard CMOS technology, consists of a transmitter and two receivers that provide two modes of operation. The transmitter consumes 575 <inline-formula> <tex-math notation="LaTeX">\mu \text{W} </tex-math></inline-formula> while transmitting a 100-kb/s signal at 4 GHz at an output power of −11.4 dBm. A single RF IO pad is used and the fully integrated matching network is shared among the transmitter and the receivers. The low-power receiver consumes 267 <inline-formula> <tex-math notation="LaTeX">\mu \text{W} </tex-math></inline-formula> and provides a single communication channel at 100 kb/s in the 4-GHz band, with a −57-dBm sensitivity. The second receiver provides a better performance and takes full advantage of the FM-UWB features, as it implements wireless communication with up to four parallel channels sharing the same RF band. It consumes 550 <inline-formula> <tex-math notation="LaTeX">\mu \text{W} </tex-math></inline-formula> and provides −68-dBm sensitivity at 100 kb/s per channel. The FM-UWB architecture can tolerate a very large reference frequency offset of up to ±8000 ppm. This unique feature potentially allows for a quartz-free synthesizer, resulting in a radio with no off-chip components.
Summary
Background
The PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) study is a prospective analysis of an international database. Here we examine front‐line treatments and ...quality of life (QoL) in patients with newly diagnosed mycosis fungoides (MF).
Objectives
To identify (i) differences in first‐line approaches according to tumour‐nodes‐metastasis‐blood (TNMB) staging; (ii) parameters related to a first‐line systemic approach and (iii) response rates and QoL measures.
Methods
In total, 395 newly diagnosed patients with early‐stage MF (stage IA–IIA) were recruited from 41 centres in 17 countries between 1 January 2015 and 31 December 2018 following central clinicopathological review.
Results
The most common first‐line therapy was skin‐directed therapy (SDT) (322 cases, 81·5%), while a smaller percentage (44 cases, 11·1%) received systemic therapy. Expectant observation was used in 7·3%. In univariate analysis, the use of systemic therapy was significantly associated with higher clinical stage (IA, 6%; IB, 14%; IIA, 20%; IA–IB vs. IIA, P < 0·001), presence of plaques (T1a/T2a, 5%; T1b/T2b, 17%; P < 0·001), higher modified Severity Weighted Assessment Tool (> 10, 15%; ≤ 10, 7%; P = 0·01) and folliculotropic MF (FMF) (24% vs. 12%, P = 0·001). Multivariate analysis demonstrated significant associations with the presence of plaques (T1b/T2b vs. T1a/T2a, odds ratio 3·07) and FMF (odds ratio 2·83). The overall response rate (ORR) to first‐line SDT was 73%, while the ORR to first‐line systemic treatments was lower (57%) (P = 0·027). Health‐related QoL improved significantly both in patients with responsive disease and in those with stable disease.
Conclusions
Disease characteristics such as presence of plaques and FMF influence physician treatment choices, and SDT was superior to systemic therapy even in patients with such disease characteristics. Consequently, future treatment guidelines for early‐stage MF need to address these issues.
What is already known about this topic?
Early‐stage mycosis fungoides is characterized by a good prognosis.
The first‐line treatment approach is typically stage based and is usually skin‐directed therapy.
What does this study add?
This multicentre prospective international study reports that real‐life treatment decisions are not limited to a stage‐based approach but are also influenced by the presence of plaques and folliculotropic mycosis fungoides.
Approximately half of the patients with early‐stage disease experienced a moderate or severe impact on their quality of life at diagnosis.
This study suggests that treatment guidelines in patients with early‐stage disease should incorporate high‐risk features and quality‐of-life evaluation.
Linked Comment: Porcu and Nikbakht. Br J Dermatol 2021; 184:594–595.
Although some of the recently proposed compact models for thermal noise in MOS transistors exhibit a good match with experimental data, we believe most of the existing compact models suffer from ...incorrect physical assumptions or modeling (e.g., absence of carrier heating, incorrect modeling of velocity saturation effect, wrong modeling of diffusivity, etc.). This brief presents a new, completely analytical thermal noise model based on consistent physical assumptions.
Charge-Based Distortion Analysis of Nanoscale MOSFETs Chicco, Francesco; Pezzotta, Alessandro; Enz, Christian C.
IEEE transactions on circuits and systems. I, Regular papers,
02/2019, Letnik:
66, Številka:
2
Journal Article
Recenzirano
Odprti dostop
This paper presents a study of MOSFETs' linearity, exploiting a simplified version of the charge-based EKV model. It allows to deduce analytically the one-tone and two-tone harmonic distortions ...introduced by the nonlinear <inline-formula> <tex-math notation="LaTeX">I_{D} </tex-math></inline-formula>-<inline-formula> <tex-math notation="LaTeX">V_{G} </tex-math></inline-formula> MOSFET characteristic as a function of the inversion coefficient. The short-channel effects are included in order to address nanoscale MOSFET performance. The analysis is validated through comparisons with the BSIM6 model and measurement results from 28-nm bulk CMOS devices. By means of this model, the designer can choose the appropriate bias region for the critical devices of a circuit depending on the system requirements.
This paper presents an overview of MOS transistor modeling for RF integrated circuit design. It starts with the description of a physical equivalent circuit that can easily be implemented as a SPICE ...subcircuit. The MOS transistor is divided into an intrinsic part, representing mainly the active part of the device, and an extrinsic part responsible for most of the parasitic elements. A complete charge-based model of the intrinsic part is presented. The main advantage of this new charge-based model is to provide a simple and coherent description of the DC, AC, nonquasi-static (NQS), and noise behavior of the intrinsic MOS that is valid in all regions of operation. It is based on the forward and reverse charges q/sub f/ and q/sub r/ defined as the mobile charge densities, evaluated at the source and at the drain. This intrinsic model also includes a new simplified NQS model that uses a bias and frequency normalization allowing one to describe the high-order frequency behavior with only two simple functions. The extrinsic model includes all the terminal access series resistances, and particularly the gate resistance, the overlap, and junction capacitances as well as a substrate network. The latter is required to account for the signal coupling occurring at RF from the drain to the source and the bulk, through the junction capacitances. The noise model is then presented, including the effect of the substrate resistances on the RF noise parameters. All the aspects of the model are validated for a 0.25-/spl mu/m CMOS process.
This paper presents the basis of the modeling of the MOS transistor for circuit simulation at RF. A physical equivalent circuit that can easily be implemented as a Spice subcircuit is first derived. ...The subcircuit includes a substrate network that accounts for the signal coupling occurring at HF from the drain to the source and the bulk. It is shown that the latter mainly affects the output admittance Y22. The bias and geometry dependence of the subcircuit components, leading to a scalable model, are then discussed with emphasis on the substrate resistances. Analytical expressions of the Y parameters are established and compared to measurements made on a 0.25-/spl mu/m CMOS process. The Y parameters and transit frequency simulated with this scalable model versus frequency, geometry, and bias are in good agreement with measured data. The nonquasi-static effects and their practical implementation in the Spice subcircuit are then briefly discussed. Finally, a new thermal noise model is introduced. The parameters used to characterize the noise at HF are then presented and the scalable model is favorably compared to measurements made on the same devices used for the S-parameter measurement.
A low-power frequency modulated-ultra-wideband (FM-UWB) receiver for short-range communications, capable of simultaneously demodulating multiple FM-UWB signals located at the same frequency, is ...presented in this paper. The proposed receiver utilizes an "approximate zero IF" architecture that uses a low-power, free-running ring oscillator as the RF LO to first convert the input signal into baseband, where it is then amplified and demodulated. Moving the most power-hungry blocks from RF to IF results in reduction of power consumption by more than one order of magnitude compared to previous implementations using the delay-line demodulator. Integrated in a 65-nm CMOS technology, the whole receiver chain consumes 423 μW from a 1-V supply while achieving -70-dBm sensitivity at a data rate of 100 kb/s at 4 GHz. Communication with up to four FM-UWB users, operating in the same band, is demonstrated, making this receiver suitable for high-density wireless sensor networks.
In linear IC's fabricated in a low-voltage CMOS technology, the reduction of the dynamic range due to the dc offset and low frequency noise of the amplifiers becomes increasingly significant. Also, ...the achievable amplifier gain is often quite low in such a technology, since cascoding may not be a practical circuit option due to the resulting reduction of the output signal swing. In this paper, some old and some new circuit techniques are described for the compensation of the amplifier's most important nonideal effects including the noise (mainly thermal and 1/f noise), the input-referred dc offset voltage as well as the finite gain resulting in a nonideal virtual ground at the input.
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