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Title: Joint Pilot Allocation and Robust Beam-Vector Design for Ultra-Dense TDD C-RAN
This paper deals with the unavailability of full CSI in ultra-dense user-centric TDD C-RAN. To reduce the channel training overhead, we consider the incomplete CSI case, where only large-scale inter-cluster CSI is available. Channel estimation for intra-cluster CSI is also considered, where we formulate a joint pilot allocation and user equipment (UE) selection problem to maximize the number of admitted UEs with fixed number of pilots. A novel pilot allocation algorithm is proposed by considering the multi-UE pilot interference. Then, we consider robust beam-vector optimization problem subject to UEs' data rate requirements and fronthaul capacity constraints, where the channel estimation error and incomplete inter-cluster CSI are considered. Simulation results demonstrate its superiority over the existing algorithms.  more » « less
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Date Published:
Journal Name:
GLOBECOM 2017 - 2017 IEEE Global Communications Conference
Page Range / eLocation ID:
1 to 5
Medium: X
Sponsoring Org:
National Science Foundation
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