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Key research themes
1. How can transmitter cooperation and common information be leveraged to mitigate interference in Gaussian interference channels?
This research theme investigates the role of partial or full transmitter cooperation and the use of common and private messages in Gaussian interference channels to improve achievable rates and approach capacity limits. It focuses on coding and cooperation schemes that enable interference mitigation through message sharing or cognitive radio settings, analyzing their impact on achievable rate regions and optimal transmission strategies.
Key finding: This paper develops a cooperative communication scheme for the two-user symmetric Gaussian interference channel enhanced by a unidirectional noiseless link with finite capacity allowing partial encoder cooperation. The study... Read more
Key finding: This work derives an achievable rate region for the discrete memoryless interference channel with common information using a novel cascaded superposition coding scheme that generalizes existing achievable regions (including... Read more
Key finding: This study establishes the capacity region of interference channels when both transmitters send private messages along with a common message to both receivers, under strong interference conditions. It models partial... Read more
2. What are effective interference avoidance techniques using signal design strategies in wireless systems to mitigate multi-user interference?
This theme focuses on adaptive and signal processing-based interference avoidance methods applicable to wireless networks, including multi-antenna systems and ultra-wideband communications. It explores frameworks that design transmit waveforms, spreading sequences, and modulation approaches (such as code division multiplexing and spectral encoding) that enable users to avoid interfering frequency/time/code resources and maximize signal-to-interference-plus-noise ratio (SINR). Studies also assess the theoretical and practical performance gains from such techniques including hardware implementations.
Key finding: The paper proposes iterative distributed algorithms that optimize the set of waveforms used by multiple transmitters in a shared wireless medium to maximize signal-to-interference ratio (SIR), resulting in waveform ensembles... Read more
Key finding: This experimental study validates, for the first time, interference mitigation over a contiguous 1.3 GHz ultra-wideband (UWB) channel using code division multiplexing (CDM)-based spreading. Analytical BER formulas are... Read more
Key finding: This work introduces a spectrally encoded multiple access technique employing M-ary phase shift keying (MPSK) with composite phase modulation applied in the frequency domain for independent data and coded multiple access. The... Read more
Key finding: This paper surveys classical and contemporary interference mitigation approaches and advocates adaptive modulation methods termed interference avoidance, where individual users adapt signal energy distribution into spectral... Read more
Key finding: This work presents advanced interference avoidance strategies targeting 3GPP cellular systems, focusing on multi-user Multiple-Input Multiple-Output (MU-MIMO) and 3D beamforming techniques. It addresses challenges such as... Read more
3. How can noise-based and modulation-based strategies enable secure and interference-resilient communication in wireless sensor and passive networks?
This research area examines noise-based intrinsic security, modulated backscatter communication, and interference-aware detection protocols geared towards ensuring interference-free, low-power, and secure communication especially in wireless sensor networks and passive sensor systems. Studies explore physical-layer security models leveraging noise and channel degrees of freedom, practical modulation designs minimizing transmission power, and run-time interference detection enabling collision-free medium access control scheduling.
Key finding: The paper investigates unconditionally secure wireless communication using noise-based schemes rooted in physical-layer security concepts like the Kirchhoff-law-Johnson-noise (KLJN) approach. It provides an... Read more
Key finding: This analytical study models wireless passive sensor networks (WPSNs) using modulated backscattering (MB) for communication, where sensor nodes modulate and reflect incident RF signals rather than generating their own... Read more
Key finding: Through experiments on MICA2 platforms, this paper disproves common assumptions equating communication range with interference range in wireless sensor networks, showing interference can occur outside communication range and... Read more
Key finding: This paper analyzes the application of noise-like ultra-short pulse signals for wireless information transmission, highlighting their broad spectral width that enables signal-to-noise ratio (SNR) enhancement via pulse... Read more