preloader

Research Projects

TICI - Research
CONGO: Compressive Online Gradient Optimization

J. Carleton, P. Vijaykumar, D. Saxena, D. Narasimha, S. Shakkottai, A. Akella

We address the challenge of zeroth-order online convex optimization where the objective function’s gradient exhibits sparsity. Our aim is to …

TICI - Research
Transformers are Provably Optimal In-context Estimators for Wireless Communications

V. T. Kunde, V. Rajagopalan, C. S. K. Valmeekam, K. Narayanan, S. Shakkottai, D. Kalathil, J.-F. Chamberland

We prove that a single layer softmax attention transformer (SAT) computes the optimal solution of canonical estimation problems in wireless …

TICI - Research
Distributionally Robust Direct Preference Optimization

Z. Xu, S. Vemuri, K. Panaganti, D. Kalathil, R. Jain, D. Ramachandran

We propose two novel distributionally robust direct preference optimization (DPO) algorithms, Wasserstein DPO (WDPO) and Kullback-Leibler DPO (KLDPO), …

TICI - Research
Multi-Objective Alignment of Diffusion Model with Reverse-Time Drift Blending

M. Cheng, F. Doudi, D. Kalathil, M. Ghavamzadeh, P. R. Kumar

We propose DiffusionBlend which enables test-time alignment of Diffusion Models to user-defined weights for objectives and regularization without …

TICI - Research
LLMZip: Lossless Text Compression using Large Language Models

C. S. K. Valmeekam, K. Narayanan, D. Kalathil, J.F. Chamberland, S. Shakkottai

We show that English text is a lot more compressible than what was believed to be possible previously. Our lossless compression algorithm combines the …

TICI - Research
Squeezed Random Khatri-Rao Product Codes

R. Ji, A. K. Pradhan, A. Heidarzadeh, K. Narayanan

In coded distributed matrix multiplication, a master node wishes to compute large-scale matrix product with the help of several worker nodes, we …

TICI - Research
DOPL: Direct Online Preference Learning for Restless Bandits with Preference Feedback

Guojun Xiong, Ujwal Dinesha, Debajoy Mukherjee, Jian Li, Srinivas Shakkottai

Addressing the limitations of conventional scalar rewards, DOPL leverages pairwise preference feedback to navigate restless multi-armed bandit …

TICI - Research
OD-Stega: LLM-based near-imperceptible steganography via optimized distributions

Y.S. Huang, P. Just, K. Narayanan, C. Tian

We explore coverless steganography using a Large Language Model (LLM) to guide an arithmetic coding decoder in generating stego-texts, aiming to embed …

TICI - Research
Over-the-Air Neural Group Testing

C. S. K. Valmeekam, K. Narayanan, A. Sprintson

We consider a wireless network where each user/sensor wishes to communicate an image to a central base station for the purpose of classifying images …

TICI - Research
A Semi-Blind Decision Directed Iterative Channel Estimation and Decoding for LDPC Coded OFDM Systems

C. S. K. Valmeekam, K. Narayanan

We propose a semi-blind decision-directed joint channel estimation and decoding algorithm for low-density parity check (LDPC) coded Orthogonal …