154 citations · 474 across the 50 of their papers we have counts for
16 papers · 1 filter
Distributed Computation over MAC via Kolmogorov-Arnold Representation
Derya Malak, Ali Tajer
Kolmogorov's representation theorem provides a framework for decomposing any arbitrary real-valued, multivariate, and continuous function into a two-layer nested superposition of a…
The Broadcast Approach in Communication Networks
Ali Tajer, Avi Steiner, Shlomo Shamai
This paper reviews the theoretical and practical principles of the broadcast approach to communication over state-dependent channels and networks in which the transmitters have acc…
Secure Estimation under Causative Attacks
Saurabh Sihag, Ali Tajer
This paper considers the problem of secure parameter estimation when the estimation algorithm is prone to causative attacks. Causative attacks, in principle, target decision-making…
Quickest Search for a Change Point
Javad Heydari, Ali Tajer
This paper considers a sequence of random variables generated according to a common distribution. The distribution might undergo periods of transient changes at an unknown set of t…
Multiaccess Communication via a Broadcast Approach Adapted to the Multiuser Channel
Samia Kazemi, Ali Tajer
A broadcast strategy for multiple access communication over slowly fading channels is introduced, in which the channel state information is known to only the receiver. In this stra…
Quick Search for Rare Events
Ali Tajer, H. Vincent Poor
Rare events can potentially occur in many applications. When manifested as opportunities to be exploited, risks to be ameliorated, or certain features to be extracted, such events…
Adaptive Sensing of Congested Spectrum Bands
Ali Tajer, Rui M. Castro, Xiaodong Wang
Cognitive radios process their sensed information collectively in order to opportunistically identify and access under-utilized spectrum segments (spectrum holes). Due to the trans…
Information Exchange Limits in Cooperative MIMO Networks
Ali Tajer, Xiaodong Wang
Concurrent presence of inter-cell and intra-cell interferences constitutes a major impediment to reliable downlink transmission in multi-cell multiuser networks. Harnessing such in…
Diversity Analysis of Symbol-by-Symbol Linear Equalizers
Ali Tajer, Aria Nosratinia, Naofal Al-Dhahir
In frequency-selective channels linear receivers enjoy significantly-reduced complexity compared with maximum likelihood receivers at the cost of performance degradation which can…
Robust Linear Precoder Design for Multi-cell Downlink Transmission
Ali Tajer, Narayan Prasad, Xiaodong Wang
Coordinated information processing by the base stations of multi-cell wireless networks enhances the overall quality of communication in the network. Such coordinations for optimiz…
(n,K)-user Interference Channels: Degrees of Freedom
Ali Tajer, Xiaodong Wang
We analyze the gains of opportunistic communication in multiuser interference channels. Consider a fully connected -user Gaussian interference channel. At each time instance onl…
Multiuser Diversity Gain in Cognitive Networks
Ali Tajer, Xiaodong Wang
Dynamic allocation of resources to the \emph{best} link in large multiuser networks offers considerable improvement in spectral efficiency. This gain, often referred to as \emph{mu…
Diversity Order in ISI Channels with Single-Carrier Frequency-Domain Equalizers
Ali Tajer, Aria Nosratinia
This paper analyzes the diversity gain achieved by single-carrier frequency-domain equalizer (SC-FDE) in frequency selective channels, and uncovers the interplay between diversity…
Beamforming and Rate Allocation in MISO Cognitive Radio Networks
Ali Tajer, Narayan Prasad, Xiaodong Wang
We consider decentralized multi-antenna cognitive radio networks where secondary (cognitive) users are granted simultaneous spectrum access along with license-holding (primary) use…
Optimal Joint Target Detection and Parameter Estimation By MIMO Radar
Ali Tajer, Guido H. Jajamovich, Xiaodong Wang +1
We consider multiple-input multiple-output (MIMO) radar systems with widely-spaced antennas. Such antenna configuration facilitates capturing the inherent diversity gain due to ind…
Beacon-Assisted Spectrum Access with Cooperative Cognitive Transmitter and Receiver
Ali Tajer, Xiaodong Wang
Spectrum access is an important function of cognitive radios for detecting and utilizing spectrum holes without interfering with the legacy systems. In this paper we propose novel…