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Purpose: The challenges associated with cochlear implant (Cl)-mediated listening are well documented; however, they can be mitigated through the provision of aided acoustic hearing in the contralateral ear--a configuration termed bimodal hearing. This study extends previous literature to examine the effect of acoustic bandwidth in the non-Cl ear for music perception. The primary aim was to determine the minimum and optimum acoustic bandwidth necessary to obtain bimodal benefit for music perception and speech perception. Method: Participants included 12 adult bimodal listeners and 12 adult control listeners with normal hearing. Music perception was assessed via measures of timbre perception and subjective sound quality of real-world music samples. Speech perception was assessed via monosyllabic word recognition in quiet. Acoustic stimuli were presented to the non-Cl ear in the following filter conditions: < 125, < 250, < 500, and < 750 Hz, and wideband (full bandwidth). Results: Generally, performance for all stimuli improved with increasing acoustic bandwidth; however, the bandwidth that is both minimally and optimally beneficial may be dependent upon stimulus type. On average, music sound quality required wideband amplification, whereas speech recognition with a male talker in quiet required a narrower acoustic bandwidth (< 250 Hz) for significant benefit. Still, average speech recognition performance continued to improve with increasing bandwidth. Conclusion: Further research is warranted to examine optimal acoustic bandwidth for additional stimulus types; however, these findings indicate that wideband amplification is most appropriate for speech and music perception in individuals with bimodal hearing., Cochlear implants (CIs) have been remarkably successful in improving quality of life and enabling high levels of speech perception. However, signal processing and design limitations continue to make the perception [...]

Bandwidth-sharing networks as introduced by Roberts and Massoulie [Roberts JW, Massoulie L (1998) Bandwidth sharing and admission control for elastic traffic. Proc. ITC Specialist Seminar, Yokohama, Japan], Massoulie and Roberts [Massoulie L, Roberts JW (1999) Bandwidth sharing: Objectives and algorithms. Proc. IEEE Infocom. (Books in Statistics, New York), 1395 14031 model the dynamic interaction among an evolving population of elastic flows competing for several links. With policies based on optimization procedures, such models are of interest both from a queueing theory and operations research perspective. In the present paper, we focus on bandwidth-sharing networks with capacities and arrival rates of a large order of magnitude compared to transfer rates of individual flows. This regime is standard in practice. In particular, we extend previous work by Reed and Zwart [Reed J, Zwart B (2010) Limit theorems for bandwidth-sharing networks with rate constraints. Revised, preprint http://people.stern.nyu.edu/jreed/Papers/BARevised.pdf] on fluid approximations for such networks: we allow interarrival times, flow sizes, and patient times (i.e., abandonment times measured from the arrival epochs) to be generally distributed, rather than exponentially distributed. We also develop polynomial-time computable fixed- point approximations for stationary distributions of bandwidth-sharing networks, and suggest new techniques for deriving these types of results. Keywords: bandwidth sharing; rate constraints; patience times; large capacity scaling; fluid limits; fixed-point approximations MSC2000 subject classification: Primary: 60K25, 60K30, 60F17, 60G57; secondary: 90B15, 90B22 OR/MS subject classification: Primary: queues, networks, limit theorems, approximations; secondary: probability, stochastic model applications History: Received March 21, 2012; revised December 18, 2013. Published online in Articles in Advance February 21, 2014., 1. Introduction. Bandwidth-sharing policies as introduced by Roberts and Massoulie [27] and Massoulie and Roberts [23] dynamically distribute network resources among a changing population of users. Processor sharing is an [...]

We investigate the effect of finite bandwidth of the incident radiation on scattering by thin layers that introduce random phase or amplitude variations. In particular, we calculate the scintillation index of the propagating radiation for smoothly varying and fractal phase screens and for random telegraph wave and checkerboard amplitude screens. Increasing the bandwidth of the incident radiation reduces the fluctuations of the scattered intensity over the whole propagation path, except in the case of the smoothly varying phase screen, where geometrical optics features in the pattern persist in the focusing region. OCIS codes: 030.1640, 030.6600, 030.6140, 290.5930, 110.1758.

We consider skyline computation when the underlying data set is horizontally partitioned onto geographically distant servers that are connected to the Internet. The existing solutions are not suitable for our problem, because they have at least one of the following drawbacks: 1) applicable only to distributed systems adopting vertical partitioning or restricted horizontal partitioning, 2) effective only when each server has limited computing and communication abilities, and 3) optimized only for skyline search in subspaces but inefficient in the full space. This paper proposes an algorithm, called feedback-based distributed skyline (FDS), to support arbitrary horizontal partitioning. FDS aims at minimizing the network bandwidth, measured in the number of tuples transmitted over the network. The core of FDS is a novel feedback-driven mechanism, where the coordinator iteratively transmits certain feedback to each participant. Participants can leverage such information to prune a large amount of local data, which otherwise would need to be sent to the coordinator. Extensive experimentation confirms that FDS significantly outperforms alternative approaches in both effectiveness and progressiveness. Index Terms--Skyline, distributed, FDS.

This paper develops a threshold power rationale that can be used to demonstrate inherent compliance for portable wireless devices with specific absorption rate (SAR) limits over the 300-6000-MHz frequency range. This is achieved first by understanding the relationship between basic antenna parameters (bandwidth, operating frequency, and distance to the body) and SAR. From this, an upper limit is determined for the power transmitted by a portable wireless device such that the SAR will not exceed the compliance limit. Based on the presented computational and measured data, an empirical formula is developed for the threshold power as a function of the aforementioned parameters. It is demonstrated that the derived threshold power is conservative for all of the low-directivity antennas studied. Computed results are also compared against practical device data (mobile telephone data collected from the manufacturers) to show that the predicted threshold power data using the proposed formula are conservative. The limitations of the proposed formula are also discussed. Index Terms--Antenna measurements, antennas, electromagnetic propagation in absorbing media, numerical analysis.

Time analog-to-digital converters (TADs) based on the power-supply voltage dependence of CMOS gate propagation delay time can be constructed solely of CMOS digital circuits and are characterized by output of the time integral of input voltage, with no dead time. This paper describes digital quadrature detection (DQD) by TAD (TAD-DQD). With TAD-DQD, the in-phase and quadrature components of the input signal, including amplitude and phase information, can be obtained simply by adding and subtracting AD-converted TAD output using a sampling frequency that is four times the carrier frequency of the target signal. As an example of the application of TAD-DQD, the standard-time and frequency-signal receiver circuits of a radio-controlled clock/watch are shown, and the experimental results demonstrate that the time code can in fact be received. Index Terms--Amplitude, analog-to-digital converter (ADC), bandwidth, CMOS digital process, digital quadrature detection (DQD), phase, radio-controlled clocks/watches, time ADC (TAD).

In this paper, techniques to overcome the errors caused by the offset, gain, sample-time, and bandwidth mismatches among time-interleaved analog-to-digital converters in a high-speed baseband digital communication receiver are presented. The errors introduced by these mismatches are corrected using least-mean-square adaptation implemented in digital-signal-processing blocks. Gain, sample-time, and bandwidth mismatches are corrected by modifying the operation of the adaptive receive equalizer itself to minimize the hardware overhead. Simulation results show that the gain, offset, sample-time, and bandwidth mismatches are sufficiently corrected for practical digital communication receivers. Index Terms--Analog-to-digital conversion, calibration, communication receiver, digital signal processing (DSP).

The dependence of multi-antenna capacity on bandwidth is characterized empirically for narrowband, wideband and ultrawideband indoor channels using spatial and polar arrays. It is shown that both the mean and the outage MIMO capacity increase with bandwidth, whilst the capacity coefficient of variation asymptotically vanishes. Index Terms--Capacity, fading, multiple-input multiple-ouput (MIMO), ultrawideband (UWB).

High resolution radars require signals with large time-bandwidth product such as CW signal and coherent pulse train (CPT). We discuss a phase-coded interrupted CW (ICW) signal which is the combination of CW signal and CPT. Phase codes used here are with perfect periodic autocorrelation. The periodic ambiguity function of ICW signals is studied including single-carrier signal and multi-carrier signal. It is interesting that the gate function has different effects on two signals and contributes to a multi-carrier ICW signal which yields nearly perfect autocorrelation. Meanwhile we also suggest an efficient receiver approach to ICW signals, which can reduce the computational burden of the processor and utilize the good properties of P3 and P4 codes.

We propose a sound approach to bandwidth selection in nonparametric kernel testing. The main idea is to find an Edgeworth expansion of the asymptotic distribution of the lest concerned. Due to the involvement of a kernel bandwidth in the leading term of the Edgeworth expansion, we are able to establish closed-form expressions to explicitly represent the leading terms of both the size and power functions and then determine how the bandwidth should be chosen according to certain requirements for both the size and power functions. For example, when a significance level is given, we can choose the bandwidth such that the power function is maximized while the size function is controlled by the significance level. Both asymptotic theory and methodology are established. In addition, we develop an easy implementation procedure for the practical realization of the established methodology and illustrate this on two simulated examples and a real data example. KEY WORDS: Choice of bandwidth parameter; Edgeworth expansion; Nonparametric kernel testing; Power function; Size function.

A 70-GHz broadband amplifier is realized in a 0.13-[micro]m CMOS technology. By using five cascaded common-source stages with the proposed asymmetric transformer peaking technique, the measured bandwidth and gain can reach 70.6 GHz and 10.3 dB under a power consumption ([P.sub.DC]) of 79.5 mW. Within the circuit bandwidth, the maximum input and output reflection coefficients are -6.1 and -10.8 dB, respectively. The group delay variation is [+ or -] 12.0 ps, and the output 1-dB compression point is 0.2 dBm at 5 GHz. With the miniaturized transformer design, the occupied core area of the circuit is only ~ 0.05 [mm.sup.2]. This amplifier demonstrates a gain-bandwidth product of 231 GHz and a GBW/[P.sub.DC] up to 2.9 GHz/mW. Index Terms--Broadband amplifier, CMOS, common-source (CS) stage, gain-bandwidth product (GBW), transformer peaking.

In this paper, an adaptive mean-shift (MS) analysis framework is proposed for object extraction and classification of hyperspectral imagery over urban areas. The basic idea is to apply an MS to obtain an object-oriented representation of hyperspectral data and then use support vector machine to interpret the feature set. In order to employ MS for hyperspectral data effectively, a feature-extraction algorithm, nonnegative matrix factorization, is utilized to reduce the high-dimensional feature space. Furthermore, two bandwidth-selection algorithms are proposed for the MS procedure. One is based on the local structures, and the other exploits separability analysis. Experiments are conducted on two hyperspectral data sets, the DC Mall hyperspectral digital-imagery collection experiment and the Purdue campus hyperspectral mapper images. We evaluate and compare the proposed approach with the well-known commercial software eCognition (object-based analysis approach) and an effective spectral/spatial classifier for hyperspectral data, namely, the derivative of the morphological profile. Experimental results show that the proposed MS-based analysis system is robust and obviously outperforms the other methods. Index Terms--Bandwidth selection, classification, high spatial resolution, hyperspectral, mean shift (MS).

In providing video-on-demand (VoD) services to a number of clients through networks, the bandwidth requirements of video transmission restrict VoD services. For this reason, many significant broadcasting-based VoD schemes have been proposed to efficiently support services. However, the broadcasting-based VoD schemes approach needs frequency channel hopping, using many channels at the same time and managing many segments of a video. These make it difficult to implement. In this paper, we propose a harmonic staggered broadcasting scheme which has a simple structure and substantially improved VoD efficiency. The proposed scheme substantially reduces the number of segments required and the frequency for switching channels. Also this new scheme performs significantly better than the existing VoD schemes in viewer's waiting time and buffer requirements with simplicity. The numerical results demonstrate that the viewer's waiting time of the harmonic staggered broadcasting scheme is close to the harmonic broadcasting scheme and the buffer requirements of this can be adjusted by a video dividing coefficient h. Index Terms--Bandwidth requirements, harmonic staggered broadcasting scheme, simple structure, video-on-demand, video-on-demand efficiency.

A compact circularly polarized (CP) vertical patch antenna is presented that employs a microstrip to slot-line transition for a wideband operation. The antenna is composed of two vertical patches, which are shaped as helix to obtain a broadband CP performance. The loop structure and the vertical overlap configuration lead to significant size reduction as much as 48% when compared to that of the printed dual-loop antenna. Simulated results agree well with the measurement, showing that the antenna possesses a wide axial ratio (AR < 3 dB) bandwidth of 28.5%, and a broad return loss ([S.sub.11] < -10 dB) bandwidth of 37.8%. Also, it has symmetric radiation patterns and low cross-polarization levels in the broadside direction over the operating bandwidth. Moreover, the antenna gain is around 8 dBi, and it is very stable across the operating bandwidth. Index Terms--Broadband antennas, circularly polarized antennas, vertical patch antennas.

In kernel discriminant analysis, one common practice is to use a fixed level of smoothing (estimated from training data) for classifying all unlabeled observations. But, in classification, a good choice of smoothing parameters also depends on the observation to be classified. Therefore, instead of using a fixed level of smoothing over the entire measurement space, it may be more useful to estimate the smoothing parameters depending on that specific observation. Here, we propose a simple method for this case-specific smoothing. Some benchmark data sets are analyzed to illustrate the performance of the proposed method. Index Terms--Bandwidth, Bayes risk, bootstrap, cross validation, kernel smoothing, misclassification rate, nearest neighbor, p-value.

Abstract In systems which serve many users there is a need to respect some fairness rules while looking for the overall efficiency. This applies among others to network design where [...]

A maximum-likelihood (ML) approach is described for the symbol rate estimation problem. The structure of the ML estimator has suggested a two-step estimation procedure, which can be used for small excess bandwidths.

A new approach to coded quadrature amplitude modulated (QAM)-multicarrier modulation (MCM) for doubly dispersive channels is presented. Results suggest the observation of low complexity, low bit-error rate and high spectral efficiency due to the implementation of the new approach.

The article proposes a power and bandwidth-efficient bit-interleaved coded modulation (BICM) with orthogonal frequency-division multiplexing (OFDM) and iterative coding (BI-COFDM-ID) using combinedccccand subcarrier grouping for broadband transmission. Findings reveal that the proposed system is capable of providing significant coding gains and achieving full channel diversity.

The article introduces wavelet transform (WT) method for automatic phase compensation to generate extremely short optical pulses with duration of a few to several femtoseconds. Findings reveal the capability of the WT method in automatic compensations of three types of ultrabroadband pulses with different characteristics.

The pulse dynamic and stability harmonically mode-locked semiconductor lasers are examined. Results suggest the capability of dynamic gain saturation is stabilizing harmonic mode-locking.

A rigorous analytic model and equivalent circuit for partially depleted absorber (PDA) photodiode is presented. Simulations indicate the mutual compatibility of the design goals of high bandwidth and resistance to optical saturation for variations in depletion-region placement.

Multiple-destination overlay multicast (MOM) is a novel multicast delivery mechanism for bandwidth-demanding applications in Internet protocol (IP) networks. Results suggest that MOM consumes less network bandwidth and less interface bandwidth.

Bandwidth management framework is presented by simulation study and algorithms for the support of Differentiated-Service-aware Traffic Engineering (DS-TE). The result shows improved bandwidth efficiency and robustness.

In a distributed discrete-event system with decentralized inFormation, agents at the various sites (e.g., controllers or diagnosers) may be required to communicate in order to correctly perform some prescribed tasks. Bandwidth, power, or security constraints motivate the design of communication protocols among agents that minimize the number of required communications. This note presents an algorithm that can synthesize such a communication protocol given a set of "essential transitions" that constitute the initial required communications. The synthesized communication protocol is shown to be minimal. Index Terms--Discrete-event systems, distributed control, distributed diagnosis, minimal communication.

A model system of resonant semiconductor microcavities analyzes the detection of thermal light by deriving original transfer matrix formalism. The studies give an insight of the gain-bandwidth limitation.

A family of algorithms is studied by installing Rate throttles in a set of upstream routers to achieve distributed throttling and to minimize overload.

A new superconducting element, a cryogenic phase detector (CPD) based on a superconductor-insulator-superconductor junction which could operate with effective bandwidth more than 100 MHz is presented.

The results of simulations and measurements of inductively loaded distributed SIS junction arrays demonstrate that the gain and sensitivity of the mixers increased when the inductive component of the IF load becomes large.

The Hybrid Fiber Coax (HFC) is a modern broadband access network, providing advanced interactive services such as Internet access, digital interactive television and cable telephony. The edge costs dominate the cost of launching new services, at the time of deployment (CapEx) as well as for maintenance (OpEx). Therefore next-generation edge devices aim at the convergence of these services and their platforms into a single multi-service infrastructure, thus sharing resources and bandwidth. The focus of this paper is on the HFC access network design for bandwidth-intensive TV services, bringing standard as well as switched broadcast technologies into play. Standard broadcast TV service deployments, offered through the Digital Video Broadcast (DVB) platform, require low installation costs, but the bandwidth consumption increases linearly with the number of available TV channels, even for very unpopular channels. Switched broadcast TV channels, offered on the (Euro-) DOCSIS platform together with other interactive unicast services such as Video on Demand, are only streamed to a node on the HFC access network if they are requested locally, thus limiting bandwidth consumption for less popular channels. We present an access network design tool, based on an analytical TV traffic model, minimizing the installation cost on the edge devices and study the influence of the most important traffic and content parameters. Index Terms--Digital TV, HFC, network convergence, switched broadcast.

Channel estimation and equalization for a class of bandwidth efficient automatic repeat request (ARQ) systems is studied. A joint multichannel estimation algorithm that exploits the structure of a symbolwise downsampled ARQ equipped network is presented.

New broadband impedance matching circuits used to increase the impedance bandwidth of the microstrip antennas for transmit applications are proposed and analyzed. A microstrip patch operating at 10.5 GHz having 12.2% bandwidth has been utilized as a reference antenna. The impedance bandwidth of the antenna has been enhanced by using negative capacitance and inductance compensation networks from 12.22% to 16.96% and 24.50%, respectively. In addition, it has been shown that the active compensation significantly improves the radiation pattern. Index Terms--Active matching, bandwidth improvement, negative capacitance, negative inductance.

One of the most major trends in modern microwave signals is the shift toward wider bandwidths. Analog wideband receiver designs can provide accommodation of the technology-stressing bandwidths, but come up to a cost of reduced flexibility. Digital approaches, alternatively, provide flexibility in receiver signal processing, but they are limited by analog-to-digital converter resolution and power consumption. In this paper, design and implementation of a 1-GHz signal bandwidth digital receiver, which uses the Kaiser window function and compensation technique, is presented. The Kaiser window reduces the spectral leakage by eliminating the discontinuities at the time window edges and the compensation uncovers the weak signal for extension of the two-signal spurious-free dynamic range (SFDR) of the receiver. The combination of both techniques extends the two-signal SFDR of the receiver to 24 dB. A novel hardware implementation of the Kaiser window and the compensation method is presented. Index Terms--Compensation, digital receiver, false alarm, instantaneous frequency measurement (IFM) receiver, Kaiser window, microwave receiver, monobit receiver, normalization, receiver-on-a-chip (ROC), super-resolution, spurious-free dynamic range (SFDR).

An instrumental variable algorithm is presented that estimates the coefficients of a continuous transfer function model directly from sampled data. The algorithm is based on instrumental variables extracted from an auxiliary, model and input and output signal derivatives estimated by filtered difference equations. As a result, this method does not require any prior knowledge of the output noise. To ensure the validity of the filtered derivative estimates, a criterion based on the Nyquist frequency and the system band-width is established. Then the concept of asymptotic consistency is applied to the proposed instrumental variable algorithm to identify the conditions for convergence of the model parameter estimates. Specifically, the asymptotic consistency conditions impose a continuous and persistent exciting constraint on the input signal. This is analogous to the persistent excitation condition for identification of discrete models. The proposed instrumental variable algorithm is demonstrated within an auto-tuning algorithm for feedback controllers based on plant inversion. In this application, the algorithm is only suitable for lower-order transfer functions that are minimum-phase and stable. These types of systems are common in industrial applications for manufacturing and process control. Here, the algorithm is experimentally validated for automatic tuning of the idle speed controller on a 4.6L Ford V-8 spark ignition engine. [DOI:10.1115/1.2432359] Keywords: auto-tuning, consistency analysis, continuous-time systems, derivative estimation, identification, instrumental variables, PRBS, system identification

In this paper, a novel bandwidth enhancement technique based on the combination of capacitive degeneration, broad-band matching network, and the regulated cascode (RGC) input stage is proposed and analyzed, which turns the transimpedance amplifier (TIA) design into a fifth-order low-pass filter with Butter-worth response. This broad-band design methodology for TIAs is presented with an example implemented in CHRT 0.18-[micro]m 1.8-V RF CMOS technology. Measurement data shows a -3-dB band-width of about 8 GHz with 0.25-pF photodiode capacitance. Comparing with the core RGC TIA without capacitive degeneration and broad-band matching network, this design achieves an overall bandwidth enhancement ratio of 3.6 with very small gain ripple. The transimpedance gain is 53 dB[OMEGA] with a group delay of 80 [+ or -] 20 ps. The chip consumes only 13.5-mW dc power and the measured average input-referred noise current spectral density is 18 pA/[square root of (Hz)] up to 10 GHz. Index Terms--Bandwidth enhancement, broad-band, matching network, regulated cascode (RGC), transimpedance amplifier (TIA).

Genetic algorithm (GA) optimization is applied to the design of planar monopole antennas, which exhibit both ultrawideband (UWB) operation and a narrow-hand frequency notch. Such an antenna is useful in applications involving wideband communications where it is desired to mitigate interference with other radio systems colocated with the operating hand. It is demonstrated in this paper that traditional band-notched planar monopole antennas exhibit asymmetry in radiation patterns within the notch band such that the attenuation provided by the antenna varies as a function of azimuth angle, which lowers the effective bandwidth of the notch. A GA optimizer, which uses of a weighted sum cost function related to impedance matching and radiation patterns at frequencies within both the wide operating band and narrow notch band, is used to improve the performance of the band-notch planar monopole antenna. A two-dimensional (2-D) matrix chromosome is used in the GA to represent a wide-range on planar element shapes. It is shown that the GA generates antenna designs that exhibit equal wideband performance as traditional band-notched designs, but have improved azimuth plane radiation pattern symmetry, which widens the effective notch bandwidth. The GA-generated antenna design is measured and compared with simulation. Index Terms--Band-notched antenna, genetic algorithm (GA) optimization, planar monopole antenna, ultrawideband (UWB) antenna.

Today's voltage regulator (VR) for the microprocessor requires a current loop to achieve adaptive voltage positioning and phase current sharing. A fundamental limitation, current loop sample hold effect, limits the control bandwidth to be pushed beyond 1/6 of the switching frequency. This paper reveals the limitation of the control bandwidth of a two-phase buck converter using peak current control scheme. The limitation can be overcome by coupling the two output inductors. A new small signal model is proposed to study the sample hold effect in coupled-inductor implementations. The relationship between the coupling coefficient and the sample hold effect is then discussed. Based on these understandings, a strongly coupled two-phase buck converter has double the bandwidth of the noncoupled VR; and this is experimentally verified. Index Terms--Coupled inductors, high bandwidth, small signal modeling.

A new estimation procedure for true unknown parameter vector [theta.sub.0] is proposed which extends the classical least squares procedure for nonlinear regression to the case where the response is subject to censoring. This new method outperforms an earlier developed method in most cases, thus this method can be recommended to practice.