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Extremely high data rate communication can potentially be achieved by combining high-order modulations and wide bandwidths at millimeter-wave (mm-wave) frequencies. However, it has been challenging to practically implement this combination, even if the SNR of the system appears to be sufficiently high. An explanation from a recent theoretical study is that the practical data rates in mm-wave systems are limited by the local oscillator (LO) white phase noise. In this letter, we present an experimental investigation on whether the white noise floor of frequency multiplied LO sources is a major noise contribution to wideband signals. Hardware measurements are performed using multi-gigabit 64 quadrature amplitude modulation (QAM) signals. The measured results show that the transmitter performance degrades as the LO noise floor increases. Hence, the LO noise floor is identified to be one primary limitation for achieving the highest possible data rate in wideband mm-wave systems. [ABSTRACT FROM PUBLISHER]

A D-band power detector (PD) consisting of a four-way power divider and four identical active PD units is proposed, where four individual PD units are derived by the input signals having the same amplitude, but a 90^\circ phase difference. The outputs of the PD units are combined, to suppress the first, second, and third harmonics due to phase cancellation. Consequently, the ripple at the output is minimized. The proposed PD is designed and manufactured in a 0.25-\mu\ m InP DHBT technology, which is characterized by on-chip measurements with both a sinusoidal signal and a binary amplitude shift-keying modulated signal at a data rate up to 13 Gb/s over different carrier frequencies from 100 to 150 GHz. Measured bit error rate for a \2 ^7 -\1 pseudorandom binary sequence is less than \10 ^-12 at the carrier frequency of 120 GHz, and less than \1.7\,\times \10 ^-5 at the carrier frequency of 150 GHz. In addition, the proposed PD achieves state-of-the-art power/energy efficiency, which exhibits the lowest energy per bit of 1.1 pJ/bit. Total dc power consumption of the PD is 15 mW. [ABSTRACT FROM PUBLISHER]

This paper studies the uneven aging of the composite insulators along the string caused by the nonuniform electric-field distribution. Sheds along the string of two 110-kV composite insulators with varied operation time on transmission lines are analyzed systematically by means of hydrophobicity and thermally stimulated current (TSC) tests, and the aging characteristics of different part of the axial sheds are compared. This paper studies the influences of the electric-field distribution along the string on the aging of composite insulators, combined with the results of electric-field simulation and electric aging tests. Results show that the higher the electric-field strength is, the worse the hydrophobicity of composite insulators surface is and the larger the amount of trap charge is. The study suggests the nonuniform electric-field distribution is the main reason for the uneven aging of the sheds along the composite insulators string. [ABSTRACT FROM PUBLISHER]

A D-band frequency quadrupler consisting of two cascaded push-push doublers is designed and manufactured in a 0.25 \mum InP DHBT technology. Each doubler has a Marchand balun implemented by broadside-coupled transmission lines, folded in a rectangular shape. The second balun, operating at a half of output frequency, is located inside of the first one for minimizing the chip size. The frequency quadrupler with a dc power consumption of 47 mW has a maximum conversion gain of 2 dB, and exhibits 12 to 25 dBc rejection ratio of the undesired first to fifth harmonics in the frequency range from 110 to 130 GHz. The quadrupler demonstrates a power efficiency of 10%, which is the highest among published quadruplers, as well as the highest conversion gain and an output power of 5 \sim 7 dBm without using power amplifiers. The chip size is 0.77 mm^2. By switching a cascode transistor, the quadrupler can also be used as an on-off keying modulator. [ABSTRACT FROM PUBLISHER]

Video-based person re-identification (ReID) matches the same people across the video sequences with rich spatial and temporal information in complex scenes. It is highly challenging to capture discriminative information when occlusions and pose variations exist between frames. A key solution to this problem rests on extracting the temporal invariant features of video sequences. In this paper, we propose a novel method for discovering temporal coherence by designing a region-level saliency and granularity mining network (SGMN). Firstly, to address the varying noisy frame problem, we design a temporal spatial-relation module (TSRM) to locate frame-level salient regions, adaptively modeling the temporal relations on spatial dimension through a probe-buffer mechanism. It avoids the information redundancy between frames and captures the informative cues of each frame. Secondly, a temporal channel-relation module (TCRM) is proposed to further mine the small granularity information of each frame, which is complementary to TSRM by concentrating on discriminative small-scale regions. TCRM exploits a one-and-rest difference relation on channel dimension to enhance the granularity features, leading to stronger robustness against misalignments. Finally, we evaluate our SGMN with four representative video-based datasets, including iLIDS-VID, MARS, DukeMTMC-VideoReID, and LS-VID, and the results indicate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Atherosclerosis screening helps the medical model transform from therapeutic medicine to preventive medicine by assessing degree of atherosclerosis prior to the occurrence of fatal vascular events. Pervasive screening emphasizes atherosclerotic monitoring with easy access, quick process, and advanced computing. In this work, we introduced five cutting-edge pervasive technologies including imaging photoplethysmography (iPPG), laser Doppler, radio frequency (RF), thermal imaging (TI), optical fiber sensing and piezoelectric sensor. IPPG measures physiological parameters by using video images that record the subtle skin color changes consistent with cardiac-synchronous blood volume changes in subcutaneous arteries and capillaries. Laser Doppler obtained the information on blood flow by analyzing the spectral components of backscattered light from the illuminated tissues’ surface. RF is based on Doppler shift caused by the periodic movement of the chest wall induced by respiration and heartbeat. TI measures vital signs by detecting electromagnetic radiation emitted by blood flow. The working principle of optical fiber sensor is to detect the change of light properties caused by the interaction between the measured physiological parameter and the entering light. Piezoelectric sensors are based on the piezoelectric effect of dielectrics. All these pervasive technologies are noninvasive, mobile, and can detect physiological parameters related to atherosclerosis screening. [ABSTRACT FROM AUTHOR]

Correcting the nonlinear frequency sweep of the tunable laser source in optical frequency domain reflectometry (OFDR) is critical for accurate measurement. It is common to correct the nonlinear frequency sweep by adding an unbalanced auxiliary interferometer in the OFDR system. However, there is a contradiction between the delay length of the auxiliary interferometer and the correction effect. A short delay length is beneficial for capturing the instantaneous frequency deviation, but it degrades the correction effect due to the low beat frequency. A longer path difference provides more references for the correction, whereas worsens the correction effect due to larger noise. This paper proposes a method introducing an acousto-optic modulator as the frequency shifter in the auxiliary interferometer, which can generate a larger beat frequency with a short delay length. With a matched signal processing method, the contradiction between the delay length and the correction effect is effectively relaxed. This method can be combined with many correction methods to improve their effects further. In experiments, the spatial resolutions and robustness for different correction methods are all improved with the proposed method. It demonstrates a wide-range effect in the promotion of OFDR technique. [ABSTRACT FROM AUTHOR]

The article presents 2021 Reviewers List of the periodical, which include Tor Aamodt, Davide Abati, and Rameen Abdal.

The complex slip characteristics between the tracks and the terrain make it difficult to build an accurate model for intelligent tracked vehicles. Both the path planning and lateral control, however, are highly dependent on the accurate tracked vehicle model. To overcome the issue, a slip model based on the instantaneous centers of rotation (ICRs) of tracks and a dual-layer adaptive unscented Kalman filter (DAUKF) are used to estimate the ICR locations in real-time without requiring prior knowledge of terrain parameters. First, the historical trajectory information is used to estimate ICR locations by the upper-layer AUKF estimator preliminarily. The ICR locations estimated in the upper-layer and the current vehicle state are then imported into the model to predict the future trajectory which can be used to estimate the offset as compensation of preliminarily estimated ICR locations by the lower-layer AUKF estimator. The proposed DAUKF is verified by simulations on MATLAB/Simulink. In order to further verify the effectiveness and practicability of the algorithm, a large number of experiments under different terrains and road conditions are implemented on the electric-drive tracked vehicle. The simulation and experimental results illustrate that the proposed DAUKF can estimate the ICR locations efficiently and accurately, which can improve the accuracy of the tracked vehicle model compared with those of extended Kalman filter (EKF), UKF, and AUKF. [ABSTRACT FROM AUTHOR]

The Landsat 5 mission is in jeopardy. Therefore, the United States Geological Survey (USGS) is exploring ways to alleviate a data gap if both Landsat 5 and 7 missions fail prior to the planned launch of Landsat 8 (known as the Landsat Data Continuity Mission) in 2013 [Randy, 2012]. Using the Chinese HJ1-CCD remote sensing data, analyses were performed on the spectral signature of these two different sensors to investigate the substitution of existing sensors for Landsat 5 TM in certain fields of research. In particular, a comparison was made between Landsat 5 TM and the HJ1-CCD in terms of orbital parameters, imaging features and spectral response characteristics, among other characteristics. Thereafter, a comparative analysis was performed on the “at-satellite” reflectance of nine pairs of remote sensing images of different land cover in China, and a mutual quantitative relationship was established. The results indicate that Landsat 5 TM and HJ1-CCD have similar orbital parameters, and the latter has a higher time resolution with advantages in its breadth and the quantity of sensors, although both have the same spatial resolution. Regarding the imaging and spectral response characteristics, although the at-satellite reflectance of HJ1-CCD is different from that of Landsat 5 TM for red, green, blue and near infra-red bands, there is still a broad correlation between HJ1-CCD and Landsat 5 TM, and the coefficient of determination approaches unity. Therefore, a mutual complementation and substitution of the at-satellite reflectance between HJ1-CCD and Landsat 5 TM images is feasible. [ABSTRACT FROM PUBLISHER]

An author index for the 2011 issue of "IEEE Transactions on Industry Applications" is presented.

On behalf of the editorial board, I would like to thank all our reviewers for their effort and dedication. As has already become customary, at the beginning of each year we recognize reviewers for their sustained and outstanding review contributions. The list of 2018 exemplary reviewers is provided below; we have 40 exemplary reviewers. [ABSTRACT FROM AUTHOR]