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We study the secure degrees of freedom (d.o.f.) of helper-assisted Gaussian wiretap channel with shared key between the transmitter and the helper. Given that the rate of the key scales with power as γ over 2 log SNR, we show that secure d.o.f. is min{1+γ over 2, 1}. The achievability proof combines real interference alignment with the artificial noise transmission technique. Using the shared key...
In the setting of the two-user single-input single-output X channel, recent works have explored the degrees-offreedom (DoF) limits in the presence of perfect channel state information at the transmitter (CSIT), as well as in the presence of perfect-quality delayed CSIT. Our work shows that the same DoF-optimal performance — previously associated to perfect-quality current CSIT — can in fact be achieved...
The problem of transmitting confidential messages in the M × K wireless X network is considered, in which each transmitter intends to send one confidential message to every receiver. In particular, the secrecy degrees of freedom (SDOF) of the considered network are studied by an artificial noise alignment (ANA) approach, which integrates interference alignment and artificial noise transmission. At...
Future mobile communication networks will require enhanced network efficiency and reduced system overhead due to their user density and high data rate demanding applications of the mobile devices. Research on Blind Interference Alignment (BIA) and Topological Interference Management (TIM) has shown that optimal Degrees of Freedom (DoF) can be achieved, in the absence of Channel State Information (CSI)...
In this paper, we consider the secure communication in a K-user multi-antenna broadcast channel (BC) with state feedback. We characterize the optimal secure degrees of freedom (SDoF) region of multiple-input single-output (MISO) channel. The SDoF region is achievable by a secret key based linear scheme, which generates analog secret keys by sending artificial noise and then performs space-time alignment...
It has been shown recently by Sun et al. that in a K user parallel Gaussian interference network, if over each sub-channel, for each user the desired signal strength is no less than the sum of the strengths of the strongest interference from this user and the strongest interference to this user (all signal strengths measured in dB scale), then separate coding over each sub-channel and treating interference...
Costa's “writing on dirty paper” result establishes that full state pre-cancellation can be attained in the Gel'fand-Pinsker problem with additive state and additive white Gaussian noise. This result holds under the assumptions that full channel knowledge is available at both the transmitter and the receiver. In this work we consider the scenario in which the state is multiplied by an ergodic fading...
We present a fully integrated CMOS stacked detection inductor and front-end receiver for NMR applications. Instead of a planar CMOS NMR detection coil, we propose a multi-turn differential stacked inductor with hollowed core. Such a structure makes available the possibility of introducing minute analyte samples directly within the sensing coil with ensuing boost in NMR measurement sensitivity. Physical...
High Frequency (HF) communications are of vital importance for modern military operations. It has the potential to move voice and data communications around the world by bouncing signals off the ionosphere, and at a fraction of the cost of heavily burdened satellite communication frequencies. However, HF-channels are touchy, unpredictable and prone to noise, fading, jamming and interference. Therefore,...
Perspective method for the monitoring and on-line modulation analysis in the HF band is presented in this paper. The workplace for the on-line analysis of analog and digital modulations consists from the digital receiver IZ225 and a PC with adequate SW. The original program for the on-line modulation signal analysis was designed in the programming environment CipherCAD. The type of modulation, its...
This paper presents analysis and design of source inductance for multistage LNA at 77-GHz band in 90 nm CMOS technology. Instead of simultaneous noise and impedance matching, the analysis shows the optimum degeneration of the single stage design for millimeter-wave frequencies. A low-power 77-GHz band LNA has been demonstrated to verify the optimization result. By using the proposed method, the LNA...
This paper presents a methodology to improve filtering in continuous time delta-sigma modulators (CTDSMs). A first order passive low pass filter is incorporated into the delta-sigma loop with a small modification of the existing active RC integrator configuration. The delay associated with the filter is compensated without any additional active components such as opamps. The proposed scheme provides...
An efficient algorithm for a link budget definition of a Bluetooth Low Energy (BLE) receiver is presented. The aim of this paper is to provide a simple procedure that the analog designers can use for a preliminary but reliable definition of the BLE RX building blocks specs. Starting from the BLE standard, the global specifications of the analog front-end are derived (noise figure, IIP3, IIP2, etc...
The average smart phone user picks up the device 1,500 times a week. Wireless communication appears to be taking over our lives but it also presents interesting challenges to RF designers. This paper contends that the mobile terminal will emerge as a central command post for most of our daily affairs and will therefore sustain an increasingly heavier load in terms of speed, power dissipation, and...
This paper details the architecture for a minimal commensal radar system which makes use of commercial FM broadcast band transmitters for the detection of aircraft. The architecture, consisting of a RF front-end, digital acquisition and radar signal processing up to the detection stage (after CFAR on a Range-Doppler plot), is intended to be small, easily portable, low power, and yet able to operate...
In this paper, we study the design of sparse graph based codes for Faster-Than-Nyquist (FTN) signaling. Using an asymptotic approach based on EXIT charts, we show that good low-density parity check codes can be designed that perform well under iterative detection and decoding and that have better performance than a FTN scheme using a code optimized for the additive white Gaussian noise channel.
An improved chassis countermeasure design that can reduce the noise radiation of Serial ATA Disk on Module (SATADOM) was presented in this article. When 3-Gbps signalling was used in SATADOM, the broadband noise will be induced and to cause radio frequency interference (RFI) problem in the WWAN band. The root-cause of the RFI issues will be analyzed based on the experimental study. The modified shielding...
A novel receiver front-end is proposed for FM/FSK modulated signal, which is transmitted from a body worn device in the MedRadio spectrum of 401–406 MHz. The front-end comprises a low noise amplifier (LNA), a zero crossing detector (ZCD) and a frequency to digital converter (FDC). The proposed architecture offers direct digitization of the input signal and is immune to LO leakage and problem of image...
The faster-than-Nyquist (FTN) signaling is a bandwidth-efficient technology which has drawn attention in the bandwidth-starved world. Since the symbols appear too early, inter-symbol interference (ISI) cannot be avoided in the receiver. Decision feedback equalization (DFE) cancellation is an efficient interference cancellation and signal detection schemes for FTN based communication system. However,...
In this paper, we propose a test of hypothesis improvement, by phase study of the analytical cross-correlation function in acoustical detection application. Robustness of false alarms probability for the Time Of Arrival (TOA) estimation represents the goal of the proposed method. After signal detection, TOA will be used to localize one receiver, thanks to a grid of transmitters (more than 3), thanks...
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