NEC

About: NEC is a company organization based out in Tokyo, Japan. It is known for research contribution in the topics: Signal & Layer (electronics). The organization has 33269 authors who have published 57670 publications receiving 835952 citations. The organization is also known as: NEC Corporation & NEC Electronics Corporation.

Glucose sensor with gel-immobilized glucose oxidase and gluconolactonase

Abstract: A glucose sensor in which a gel is in contact with a pH sensing element The gel contains immobilized glucose oxidase and gluconolactonase (EC 31117) Gluconolactonase is present in an amount effective to accelerate the hydrolysis of D-glucono-δ-lactone

Local moment formation in quantum point contacts.

Abstract: Spin-density-functional theory of quantum point contacts (QPCs) reveals the formation of a local moment with a net of one electron spin in the vicinity of the point contact---supporting the recent report of a Kondo effect in a QPC. The hybridization of the local moment to the leads decreases as the QPC becomes longer, while the on site Coulomb-interaction energy remains almost constant.

Guarded evaluation: pushing power management to logic synthesis/design

Abstract: The need to reduce the power consumption of the next generation of digital systems is clearly recognized at all levels of system design. At the system level, power management is a very powerful technique and delivers large and unambiguous savings. The ideas behind power management can be extended to the logic level. This would involve determining which parts of a circuit are computing results that will be used and which are not. The parts that are not needed are then "shut off." This paper describes an approach termed guarded evaluation, which is an implementation of this idea. A theoretical framework and the algorithms that form the basis of the approach are presented. The underlying idea is to automatically determine the parts of the circuit that can be disabled on a per-clock-cycle basis. This saves the power used in all the useless transitions in those parts of the circuit. Initial experiments indicate substantial power savings and the strong potential of this approach for a large number of benchmark circuits. While this paper presents the development of these ideas at the logic level of design, the same ideas have direct application at the register-transfer level of design also.

A 28-GHz CMOS Phased-Array Beamformer Utilizing Neutralized Bi-Directional Technique Supporting Dual-Polarized MIMO for 5G NR

Abstract: This article presents a low-cost and area-efficient 28-GHz CMOS phased-array beamformer chip for 5G millimeter-wave dual-polarized multiple-in-multiple-out (MIMO) (DP-MIMO) systems. A neutralized bi-directional technique is introduced in this work to reduce the chip area significantly. With the proposed technique, completely the same circuit chain is shared between the transmitter and receiver. To further minimize the area, an active bi-directional vector-summing phase shifter is also introduced. Area-efficient and high-resolution active phase shifting could be realized in both TX and RX modes. In measurement, the achieved saturated output power for the TX-mode beamformer is 15.1 dBm. The RX-mode noise figure is 4.2 dB at 28 GHz. To evaluate the over-the-air performance, 16 H+16 V sub-array modules are implemented in this work. Each of the sub-array modules consists of four 4 H+4 V chips. Two sub-array modules in this work are capable of scanning the beam from −50° to +50°. A saturated EIRP of 45.6 dBm is realized by 32 TX-mode beamformers. Within 1-m distance, a maximum SC-mode data rate of 15 Gb/s and the 5G new radio downlink packets transmission in 256-QAM could be supported by the module. A $2\times 2$ DP-MIMO communication is also demonstrated with two 5G new radio 64-QAM uplink streams. Thanks to the proposed area-efficient bi-directional technique, the required core area for a single element-beamformer is only 0.58 mm2. Compact and low-cost 5G millimeter-wave MIMO systems could be realized.

The transition and autocorrelation structure of tes processes

Abstract: TES (Transform-Expand-Sample) is a versatile class of stochastic sequences which can capture arbitrary marginals and a wide variety of sample path behavior and autocorrelation functions. In TES, the initial variate is uniform on [0,1) and the next variate is obtained recursively by taking the fractional part (i.e., modulo-1 reduction) of a linear autoregressive scheme. We show how this class gives rise to uniform Markovian sequences in a general and natural way, by observing that marginal uniformity is closed under modulo-1 addition of an independent variate with arbitrary distribution. We derive the transition function of TES sequences and the autocovariance function of transformed TES sequences using Fourier and Laplace Transform methods. The autocovariance formulas are amenable to fast and accurate calculation and provide the theoretical basis for a computer-based methodology of heuristic TES modeling of empirical data. A companion paper contains various examples which show the efficacy of the TES appr...