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This paper presents a 1MHz bandwidth, ΔƩ fractional-N PLL as the frequency synthesizer for LTE. A noise cancellation path composed of a novel hybrid ΔƩ DAC with 9 output bits is incorporated into the PLL in order to cancel the out-of-band phase noise caused by the quantization error. Further, a re-timing circuit is proposed to reduce the nonlinearity in the Charge Pump and provide pulse shaping si

Weak alignment of requirements engineering (RE) with verification and validation (VV) may lead to problems in delivering the required products in time with the right quality. For example, weak communication of requirements changes to testers may result in lack of verification of new requirements and incorrect verification of old invalid requirements, leading to software quality problems, wasted ef

Pathloss is typically modeled using a log-distance power law with a large-scale fading term that is log-normal. However, the received signal is affected by the dynamic range and noise floor of the measurement system used to sound the channel, which can cause measurement samples to be truncated or censored. If the information about the censored samples is not included in the estimation method, as i

Families of generalized spatially-coupled low-density parity-check (GSC-LDPC) code ensembles can be formed by terminating protograph-based generalized LDPC convolutional (GLDPCC) codes. It has previously been shown that ensembles of GSC-LDPC codes constructed from a protograph have better iterative decoding thresholds than their block code counterparts, and that, for large termination lengths, the

The Theory of Characteristic Modes provides a convenient tool for designing multi-antennas for MIMO applications, as it enables orthogonal radiation patterns to be excited in a given antenna structure. Moreover, the frequency behavior of the modes reveals interesting wideband properties of the structure. However, the tracking of characteristic modes over frequency remains a challenge, especially w

This paper presents an energy-efficient sorted QR decomposition (SQRD) processor for 3GPP LTE-Advanced (LTE-A) systems. The processor adopts a hybrid decomposition scheme to reduce computational complexity and provides a wide-range of performance complexity trade-offs. Based on the energy distribution of spatial channels, it switches between the brute-force SQRD and a low-complexity group-sort QR-

The 14th edition of International Telecommunications Network Strategy and Planning Symposium (shortly: Networks 2010) held in Warsaw, Poland. Networks 2010 was a four-day professional and scientific event organized by Warsaw University of Technology in co-operation with Polish Association of Telecommunication Engineers (SIT). The conference was focused on network design and planning methods includ

In this paper a frequency compensation method for operational transconductance amplifiers is proposed, which poses no power overhead compared to Miller compensation, while improving the 3dB bandwidth, the unity gain frequency and the slew rate. The technique employees positive feedback to introduce an extra left half plane zero to cancel a pole.The phase margin shows good robustness against proces

The feasibility of digesting energy crops supplemented with macro- and micronutrients instead of manure, without the commonly applied long hydraulic retention time (HRT), was investigated in long-term, single-stage continuous stirred tank processes. The crops used were mixtures of sugar beets, maize and whole crop triticale. The organic loading rate (OLR) measured as a total solid (TS) was 1.5-5.5

This paper presents a multi-bit, continuous time delta-sigma modulator with 20 MHz bandwidth implemented in 65nm CMOS for cellular communication. The modulator features a third order, single loop filter and a 4-bit internal quantizer operating at 640 MHz. The DACs are resistive for lower thermal noise compared to the current-steering DACs and nonreturn-to-zero DAC pulse is used to reduce the clock

A large ensemble of regional climate model projections was investigated regarding if and when they show an emergence of significant climate change signals in seasonal temperature and precipitation within Europe. The influence of the North Atlantic Oscillation (NAO), as simulated in the projections, was investigated. In most parts of Europe, the projections indicate robust emergence of temperature

Finding optimal routes and spectrum allocation in flexgrid optical networks, known as the RSA problem, is an important design problem in transport communication networks. The problem is NP -hard, and its intractability becomes profound when network instances with several tens of nodes and several hundreds of demands are to be solved to optimum. In order to deal with such instances, large-scale opt

With the densification of nodes in cellular networks, free space optic (FSO) connections are becoming an appealing low cost and high rate alternative to copper and fiber backhaul solutions for wireless communication systems. To ensure a reliable cellular backhaul, provisions for redundant disjoint paths between the nodes must be made in the design phase. This paper aims at finding a cost-effective

[Context & motivation] For market-driven software product developing organizations operating on a competitive open market, it is important to plan the product’s releases so that they can reach the market as early as possible with a competitive level of quality compared to its competitors' products. Hence, quality requirements can be seen as a key competitive advantage. The QUPER model was deve

A Multi-band CMOS front-end was designed and fabricated in a 0.13μm CMOS process. The front-end employs a common-gate low noise amplifier (LNA) with capacitive cross coupling (CCC) technique and a double balanced mixer. The band selection is performed by switching capacitors in and out of the LNA load, changing the resonance frequencies ranging from 2.5GHz to 4.5GHz in 16 different frequency bands

Background: The fix-cache approach to regression test selection was proposed to identify the most fault-prone files and corresponding test cases through analysis of fixed defect reports. Aim: The study aims at evaluating the efficiency of this approach, compared to the previous regression test selection strategy in a major corporation, developing embedded systems. Method: We launched a post-hoc

A receiver front-end supporting contiguous and non-contiguous intra-band carrier aggregation scenarios with a fully integrated spectrum sensor that can detect both in-gap and out-of-band blockers has been implemented in 65nm CMOS technology. An NF of 2.5dB is achieved using a noise canceling LNTA, and linearized OTAs are used to achieve an IIP3 improvement of up to 6.5dB in-band and 11dB at the fi

Efficient scope management is a core part of software release management and often a key factor in releasing successful software products to the market. In a case when not all the requirements for the next software product release are known ‘a priori’ and when new requirements are issued throughout the project, the risk of overscoping by including more functionality than can be implemented increas

This chapter focuses on taxation in Africa since 1900. Using existing data and insights from the literature, the chapter documents taxes collected by colonial and post-colonial states, exploring what was taxed, the types of taxes, the tax revenue patterns and the socio-political contexts shaping taxation policies. It begins by discussing the fundamental principles of taxation and forms of direct a