Title
Graph Signal Restoration Using Nested Deep Algorithm Unrolling
Abstract
Graph signal processing is a ubiquitous task in many applications such as sensor, social, transportation and brain networks, point cloud processing, and graph neural networks. Often, graph signals are corrupted in the sensing process, thus requiring restoration. In this paper, we propose two graph signal restoration methods based on deep algorithm unrolling (DAU). First, we present a graph signal denoiser by unrolling iterations of the alternating direction method of multiplier (ADMM). We then suggest a general restoration method for linear degradation by unrolling iterations of Plug-and-Play ADMM (PnP-ADMM). In the second approach, the unrolled ADMM-based denoiser is incorporated as a submodule, leading to a nested DAU structure. The parameters in the proposed denoising/restoration methods are trainable in an end-to-end manner. Our approach is interpretable and keeps the number of parameters small since we only tune graph-independent regularization parameters. We overcome two main challenges in existing graph signal restoration methods: 1) limited performance of convex optimization algorithms due to fixed parameters which are often determined manually. 2) large number of parameters of graph neural networks that result in difficulty of training. Several experiments for graph signal denoising and interpolation are performed on synthetic and real-world data. The proposed methods show performance improvements over several existing techniques in terms of root mean squared error in both tasks.
Year
DOI
Venue
2022
10.1109/TSP.2022.3180546
IEEE TRANSACTIONS ON SIGNAL PROCESSING
Keywords
DocType
Volume
Signal processing algorithms, Image restoration, Signal restoration, Noise reduction, Task analysis, Symmetric matrices, Optimization, Graph signal processing, signal restoration, deep algorithm unrolling, Plug-and-Play ADMM
Journal
70
ISSN
Citations 
PageRank 
1053-587X
0
0.34
References 
Authors
0
5
Name
Order
Citations
PageRank
Masatoshi Nagahama100.68
Koki Yamada201.69
Yuichi Tanaka36310.96
Stanley H. Chan440330.95
Y. C. Eldar56399458.37