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Today almost every system or service, e.g., water, power supply, transportation, etc. is dependent on IT systems, and failure of these systems have serious and negative effects on the society. IT incidents are critical for the society as they can stop the function of critical systems and services. Moreover, in a software engineering context risk analysis is an important activity for the developmen
A short range FM transmitter is presented. It uses an architecture where the output frequency of a phase locked loop (PLL) is modulated by varying the division number of the feedback divider, using the 1-bit output of a ΔΣ ADC. The measured total harmonic distortion (THD) plus noise is less than 1% at 75 kHz deviation. The transmitter is fully integrated in a 0.13µm CMOS process and the core area
Abstract in UndeterminedThis paper presents an inductorless ultra-low power radio receiver front-end intended for applications such as sensor networks and medical implants. It consists of low noise amplifier, quadrature mixer, and a frequency divider for the generation of quadrature local oscillator signals. The power consumption is just 282μW from a 0.9V supply when it operates in the 915 MHz ISM
This paper presents an energy efficient adaptive QR decomposition scheme for Long Term Evolution Advance (LTE-A) downlink system. The proposed scheme provides a performance robustness to fluctuating wireless channels while maintaining lower workload on a reconfigurable hardware. A statistic based algorithm-switching strategy is employed in the scheme to achieve workload reduction and stable comput
Three mm-wave pulse generation circuits fabricated in a standard 65nm CMOS process are presented. Two versions are based on the cross-coupled NMOS LC-VCO (500um × 300 um), and one is based on the Colpitts VCO (600um × 300 um). No additional buffers are used in the cross-coupled versions, as they are directly loaded by 50 Ohms through a balun. They can produce measured pulses exceeding 8dBm peak ou
A divider-less all digital phase locked loop (ADPLL) with a high frequency resolution is implemented. All blocks excluding digitally controlled oscillator (DCO) and time to digital converter (TDC) are realized in standard digital design which consumes less power. The DCO core adopts an improved source-varactor LC resonant tank to achieve a 20KHz frequency resolution. With the help of an additional
A 24 GHz 2-path beamforming receiver front-end in 90 nm CMOS is presented. It consists of two direct conversion front-ends followed by a baseband block performing phase rotation and signal combination. The baseband phase rotation is performed by combining the quadrature phases using digitally controlled weights, achieving a phase resolution of 11 degrees. From each of the two inputs the front-end
Analytical Multiple-Input Multiple-Output (MIMO) models are often attractive due to their low complexity when analyzing possibilities and limitations in the system. In this paper we outline a a possible dual link extension of an analytical MIMO channel model and investigate its suitability based on measurements of a dual link MIMO scenario. The extension is based on the correlation matrix distance
In secure computing systems, isolation between different components is normally the basis for security. However, ab- solute isolation is seldom desired nor practical. Often for the system to function, a secure communication channel between otherwise isolated components is also needed. In this work, we consider implementation of the secure Remote Procedure Call (RPC) mechanism defined by the Global
Issue management in market-driven software projects is constantly under time pressure. A limited set of developers must share their time between developing features for the next release and resolving reported issues. Project managers need to find the appropriate balance between a high quality product and fast time to market. We study a telecom company in Sweden developing embedded systems for a co
Massive multiple-input multiple-output (MIMO) is one of the main candidates to be included in the fifth generation (5G) cellular systems. For further system development it is desirable to have real-time testbeds showing possibilities and limitations of the technology. In this paper we describe the Lund University Massive MIMO testbed – LuMaMi. It is a flexible testbed where the base station operat
