Efficient optimization of integrated spiral inductor with bounding of layout design parameters

In this paper we present an efficient method of determining the optimized layout of on chip spiral inductor. The method initially identifies the feasible region of optimization by developing layout design parameter bound curves for a large range of physical inductance values that satisfies the same area specification. For any desired inductance value the upper and lower bounds of the optimization variables are determined graphically. An enumeration algorithm implemented finds the global optimum layout that gives the highest quality factor in less than 1 s of CPU time with less function evaluations. The optimization method also gives the performance of all possible combinations that results the same inductance value. Subsequently important fundamental tradeoff of the design like quality factor and area, quality factor and inductance, quality factor and operating frequency, maximum quality factor and the peak frequency is explored in few seconds. The method also gives other valuable information such as sensitivity of the inductance and quality factor to the layout design parameters. The accuracy of the proposed method is verified using a 3D electromagnetic simulator.     

A large class of binary ZCZ sequence families constructed by period doubling

In an Approximately Synchronized Code Division Multiple Access （AS-CDMA） communication system, a family with large number of Zero Correlation Zone （ZCZ） sequences is desired, which can satisfy the rapid increase of users. This paper presents a method to generate a （2L,2M, ZCZ＇）-ZCZ sequence family from an original （L,M,ZCZ）-ZCZ sequence family, where ZCZ＇ = ZCZ if ZCZ is even and ZCZ＇ =ZCZ - 1 if ZCZ is odd. This method can also recursively act on a ZCZ sequence family to construct a series of ZCZ sequence families with large sequence number and zero correlation zone length identical to or one less than that of original ZCZ sequences.     

RF Testing on a Mixed Signal Tester

In this paper, testing of radio frequency (RF) devices with mixed-signal testers is discussed. General purpose automatic test equipment (ATE) will be used. In this paper, a more universal test structure utilizing RF building blocks is proposed. A global positioning system (GPS) device is used as an example to illustrate how to develop the RF test plan with this usage. The test plan developed includes fast, cost-effective and dedicated circuitry.

LLE-based classification algorithm for MMW radar target recognition

In this paper, a new multiclass classification algorithm is proposed based on the idea of Locally Linear Embedding (LLE), to avoid the defect of traditional manifold learning algorithms, which can not deal with new sample points. The algorithm defines an error as a criterion by computing a sample’s reconstruc-tion weight using LLE. Furthermore, the existence and characteristics of low dimensional manifold in range-profile time-frequency information are explored using manifold learning algorithm, aiming at the problem of target recognition about high range resolution MilliMeter-Wave (MMW) radar. The new algo-rithm is applied to radar target recognition. The experiment results show the algorithm is efficient. Com-pared with other classification algorithms, our method improves the recognition precision and the result is not sensitive to input parameters.     

Electrical and optical properties of deep-red top-surface-emittinglasers

By studying thermal behavior of all-MBE surface-emitting lasers, barrier heights and optimum cavity design parameters are obtained. The barrier heights for holes between hetero-interfaces of Al_0.3Ga_0.7As-Al_0.65Ga_0.35As and AlAs-Al_0.65Ga_0.35As (Δx=-0.35) are measured to be 77 meV at zero bias for the deep-red top-surface-emitting laser. The barrier height decreases linearly with forward bias voltage, explaining the nonlinearity in current-voltage characteristics of the top-surface-emitting laser. The contribution of electrons to electrical resistance is estimated to be negligibly small compared to that of holes for the structure consisting of Δ_x =0.35. Minimum threshold current and maximum differential quantum efficiency observed around 200 K indicate slight mismatch between gain maximum and Fabry-Perot resonance for the deep-red top-surface-emitting laser     

Chemiluminescent and Antioxidant Micelles as Theranostic Agents for Hydrogen Peroxide Associated‐Inflammatory Diseases

Hydrogen peroxide (H₂O₂) is one of essential oxygen metabolites in living organisms, but is generated in large amounts during inflammatory responses. Therefore, H₂O₂ has great potential as diagnostic and therapeutic markers of several inflammatory and life‐threatening diseases. Here, chemiluminescent and antioxidant micelles are reported as novel theranostic agents for H₂O₂‐associated inflammatory diseases. The chemiluminescent micelles composed of amphiphilic block copolymer Pluronic F‐127, hydroxybenzyl alcohol‐incorporated copolyoxalate (HPOX) and fluorescent dyes perform peroxalate chemiluminescence reactions to detect H₂O₂ as low as 100 nM and image H₂O₂ generated in inflamed mouse ankles. The micelles encapsulating HPOX reduce the generation of reactive oxygen species in lipopolysaccharide (LPS)‐activated macrophages by scavenging overproduced H₂O₂ and releasing antioxidant hydroxybenzyl alcohol (HBA). They also exert inhibitory effects on H₂O₂‐induced apoptosis. HPOX‐based chemiluminescent and antioxidant micelles have great potential as a theranostic agent for H₂O₂‐associated inflammatory diseases.     

Noncoherent spectral optical CDMA system using 1-D subtracted square codes of all transmitters in one optical line terminal

We propose a family of one-dimensional subtracted square codes in the spectral amplitude coding optical code division multiple access system. The proposed codes perform the subtraction and multiplication operations to give one-to-one mappings function, which produces the code sequences of 1-D subtracted square codes. The proposed structure uses one optical line terminal to produce all of the transmitters. This proposed system overcomes the interference from other simultaneous users, known as multiuser interference, and the cross-correlations suppress the phase-induced intensity noise. In numerical simulations using the proposed 1-D subtracted square codes, we show that 83 simultaneous users can be supported at a bit error rate of \(10^{-9}\). This number of simultaneous users in the proposed system using the 1-D subtracted square codes is superior to that in the other systems using the 1-D M sequence codes, 1-D RSQC codes, and 1-D ESP codes. The proposed system using the 1-D subtracted square codes achieves a data transmission rate of 3.2 Gbps.     

94 GHz down-conversion mixer with gain enhanced Gilbert cell in 90 nm CMOS

This paper introduces an adaptive semiblind background calibration of timing mismatches in a two-channel time-interleaved analog-to-digital converter (TIADC). By injecting a test tone at the frequency of half the overall sampling frequency of TIADC, the timing mismatch between two sub-ADCs can be quickly estimated with great accuracy without affecting the normal operation of the TIADC. The estimated coefficient can then be used in compensation module formed by a fixed structure to calibrate the timing mismatches. Simulation results demonstrate the effectiveness of the proposed estimation and correction technique.     

A New Method Modifying Single Miller Feedforward Frequency Compensation to Drive Large Capacitive Loads: Putting an Attenuator in the Path

A new method to compensate three-stage amplifier to drive large capacitive loads is proposed in this paper. Gain Bandwidth Product is increased due to use an attenuator in the path of miller compensation capacitor. Analysis demonstrates that the gain bandwidth product will be improved significantly without using large compensation capacitor. Using a feedforward path is deployed to control a left half plane zero which is able to cancel out first non-dominant pole. A three stage amplifier is simulated in a 0.18 μm CMOS technology. The purpose of the design is to compensate three-stage amplifier loading 1000 pF capacitive load. The simulated amplifier with a 1000 pF capacitive load is performed in 3.3 MHz gain bandwidth product, and phase margin of 50. The compensation capacitor is reduced extremely compared to conventional nested miller compensation methods. Since transconductance of each stage is not distinct, and it is close to one another; as a result, this method is suitable low power design methodology.     

A 700 MHz laser radar receiver realized in 0.18 μm HV-CMOS

This study presents a CMOS receiver chip realized in 0.18 µm High-Voltage CMOS (HV-CMOS) technology and intended for high precision pulsed time-of-flight laser range finding utilizing high-energy sub-ns laser pulses. The IC chip includes a trans-impedance preamplifier, a post-amplifier and a timing comparator. Timing discrimination is based on leading edge detection and the trailing edge is also discriminated for measuring the width of the pulse. The transimpedance of the channel is 25 kΩ, the uncompensated walk error is 470 ps in the dynamic range of 1:21,000 and the input referred equivalent noise current 450 nA (rms).