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This paper presents a hardware architecture of pulse shaping filter used in multicarrier systems. The filter can be configured to be used for both transmitter and receiver with limited overhead. Generic implementation complexity analysis for a filter in a multicarrier system with N sub-carriers is presented, while the implemented architecture is for a system with 128 sub-carriers. The pulse shapin

In this paper, we present a novel approach for the design of rate-maximizing channel shortening detectors with soft feedback side information for frequency-selective channels. The detector is a soft-input soft-output detector and constitutes one of the components of an iterative receiver. The design optimization is performed from an information-theoretic perspective where we maximize the achievabl

This paper presents a front-end architecture for fully integrated 60 GHz phased array receivers. It employs LO-path beamforming using a phase controlled phase-locked loop (PC-PLL). To demonstrate the architecture a circuit is implemented featuring a two stage low noise amplifier, two cascaded active mixers, and a PC-PLL. The receiver downconverts the 60 GHz signal in two steps, using LO signals fr

In this work a 2.2 GHz quadrature receiver front-end suitable for low-power applications is presented. The low-noise amplifier, the mixer and the voltage-controlled oscillator are merged into a single stage, making the circuit capable of extreme current reuse while keeping it still functional at low supply voltage. A careful linear time-variant analysis is proven to be necessary to accurately pred

As new systems and applications are introduced for next-generation wireless systems, the propagation channels in which they operate need to be characterized. This paper discusses propagation channels for four types of next-generation systems: (i) distributed Multiple-Input Multiple-Output (MIMO) and Cooperative MultiPoint (CoMP), systems, which require the characterization of correlation between c

The Haro 11 galaxy merger is the closest known Lyman continuum (LyC) leaker and a strong Lyman-α (Lyα) emitter, making it an important analogue of the high-z galaxies that reionised the early Universe. To investigate how Haro 11’s properties arise, we perform a radiation hydrodynamics simulation of the merger, and create mock observations of LyC, Lyα, and Hα, from which we compute their luminositi

It is well-known that the radio wave propagation mechanisms inside a tunnel are different from the typical outdoor and indoor situations. Since the tunnels represent a significant type of vehicular environments, understanding the channel characteristics for the in-tunnel scenario is crucial for intelligent transport systems design. A widely used tool for simulating channel characteristics for outd

TV-on-Demand service has become one of the most popular Internet applications that continuously attracts higher user interests. With rapidly increasing user demand, the existing network conditions may not be able to ensure low start-up delay of video playback. Prefetching has been broadly investigated to cope with the start-up latency problem which is also known as user perceived latency. In this

Due to changes in the development practices at Axis Communications, towards continuous integration, faster regression testing feedback is needed. The current automated regression test suite takes approximately seven hours to run which prevents developers from integrating code changes several times a day as preferred. Therefore we want to implement a highly selective yet accurate regression testing

Measurement results of an analog channel decoder in 65 nm CMOS are presented. We target ultra compact and low power applications with low to medium throughput requirements. The decoding core is designed for (7,5)(8) convolutional codes and takes 0.104 mm(2) on silicon. The degrading effects of analog imperfections are investigated and the presented results allow power, performance and throughput t

Industry--academia collaboration is critical for empirical research to exist. However, there are many obstacles in the collaboration process. This paper reports on the experiences gained by the author, in a 2-year collaboration project on software testing which involved on-site work by the researcher in the industry premises. Based on notes, minutes of meetings, and progress reports, the project h

A order 3-bit continuous-time (CT) ΔΣ ADC is presented in this paper. The design equations starting from a discrete-time reference modulator to the circuit implementation are given. The non-return to zero (NRZ) DAC pulses have a half clock cycle loopdelay which is corrected by the feedforward (also known as PI) loop delay compensation, and nonlinearities in the DACs are suppressed by data-weighted

[Context and Motivation] The main role of requirements engineering (RE) is to guide development projects towards implementing products that will appeal to customers. To effectively achieve this RE needs to be coordinated with and clearly communicated to the later software development activities. [Question/Problem] Communication gaps between RE and other development activities reduce coordination a

Clustering is a key concept of existing MIMO channel models, such as the COST 2100 model. Parameter based clustering has been studied for a while, but how parameter based clusters relate to the physical environment is not well known yet. A measurement based ray launching tool is developed and used for studying clustering and its relation to physical scatterers. By using estimated angles and delays

The problem of burst losses in OBS networks has an impact on the service quality perceived by end users. In order to guarantee certain level of Service Quality (QoS) in terms of burst losses, wavelength resources have to be dimensioned properly. In this paper, we address the problem of the Virtual Topology (VT) design that concerns the establishment of explicit routing paths and the allocation of

This article presents an architecture of a Digital Front-End Receiver (DFE-Rx) for the next-generation mobile terminals. A main focus is placed in flexibility, scalability and concurrency. The architecture is capable of detecting, synchronizing and reporting carrier-frequency offset, of multiple concurrent radio standards. The proposed receiver is fabricated in a 65nm CMOS low power high-VT cell t