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In this paper a synchronized dual input-channel multi-mode Software Defined Radio receiver platform that we built originally is presented. The receiver platform compatible with the GSM, WCDMA, and Wi-Fi standards can detect and identify the surrounding base stations and access points. It features wide frequency range, high adaptive sampling rate and especially dual phase coherent receiving channel

The purpose of the risk management process, RiskUse is to provide practitioners, mainly risk managers with a software risk management process that has a well-defined user perspective. The aim is to present a risk management process that allows the development organisation to perform adequate risk management activities that can ensure that the developed software is safe from a user perspective.

The pathloss exponent and the variance of the large-scale fading are two parameters that are of great importance when modeling or characterizing wireless propagation channels. The pathloss is typically modeled using a single-slope log-distance power law model, whereas the large-scale fading is modeled using a log-normal distribution. In practice, the received signal is affected by noise and it mig

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

The COST2100 channel model is a reference channel model which provides dynamic multiple-input multiple-output channel responses for radio system simulations. In this paper, channels created by the COST2100 model were compared to channel measurements in order to understand behaviours of the model. Model parameters of the COST2100 model were derived by dynamic double-directional channel measurements

A Vernier Gate-Ring-Oscillator (GRO) Time to Digital Converter (TDC) is proposed and implemented in 90-nm CMOS process technology. It utilizes two GRO chains as the delay lines. The time resolution is determined by the difference between two delays, so not limited by the process. Moreover, the quantization noise can be first-order shaped by the gated behavior in the oscillators, which further impr

The limited volume of mobile handset and the phenomenon of chassis excitation complicate the design of multiple antennas for MIMO applications. In this work, a compact co-located dual-antenna system implemented on one edge of a 100 mm by 40 mm chassis is proposed for operation below 1 GHz. The dual-antenna structure includes a folded monopole to excite the fundamental electric dipole mode of the c

In this note, we deduce a bound between fast algebraic immunity and higher order nonlinearity (it is the first time that a bound between these two cryptographic criteria is given), and find that a Boolean function should have high r-order nonlinearity to resist fast algebraic attacks. As a corollary, we find that no matter how much effort we make, the Tu-Deng functions cannot be repaired in a stan