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Title: Robust Wirtinger Flow Algorithm for Channel Coded Blind Demixing
As applications of Internet-of-things (IoT) rapidly expand, unscheduled multiple user access with low latency and low cost communication is attracting growing more interests. To recover the multiple uplink signals without strict access control under dynamic co-channel interference environment, the problem of blind demixing emerges as an important obstacle for us to overcome. Without channel state information, successful blind demixing can recover multiple user signals more effectively by leveraging prior information on signal characteristics such as constellations and distribution. This work studies how forward error correction (FEC) codes in Galois Field can generate more effective blind demixing algorithms. We propose a constrained Wirtinger flow algorithm by defining a valid signal set based on FEC codewords. Specifically, targeting the popular polar codes for FEC of short IoT packets, we introduce signal projections within iterations of Wirtinger Flow based on FEC code information. Simulation results demonstrate stronger robustness of the proposed algorithm against noise and practical obstacles and also faster convergence rate compared to regular Wirtinger flow algorithm.  more » « less
Award ID(s):
2009001 2029027
PAR ID:
10347284
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
IEEE International Conference on Communications
ISSN:
1938-1883
Page Range / eLocation ID:
4498-4503
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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