Iterative Rank Minimization For Broadcast Beamforming

Demir, Özlem Tuğfe
Tuncer, Temel Engin
Optimization problem of broadcast beamforming is nonconvex due to rank condition. Semidefinite relaxation (SDR) method is proposed to solve this problem. However, in certain cases, the performance of SDR becomes unacceptable. In this paper, an equivalent formulation of the original problem without rank condition is found. An iterative algorithm which is shown to converge to a rank one solution is presented. Experimental results show that the proposed algorithm is very effective and gives better results than other existing approaches.


Demir, Özlem Tuğfe; Tuncer, Temel Engin (2013-09-13)
Transmit beamformer design usually results suboptimum bearnformers in multicast scenario. In this paper, discrete phase only beamformer design is considered. The design problem is cast in such a form that the solution is always feasible and optimum beamformer can be found using the branch and cut algorithm. Beamformer phase terms and their interrelations are expressed with a set of cosine vectors which lead to linear set of constraint equations that can be solved with mixed integer linear prograrmning. It i...
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Optimum Discrete Max-Min Style Broadcast Beamforming Design
Demir, Özlem Tuğfe; Tuncer, Temel Engin (2014-04-25)
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Demir, Özlem Tuğfe; Tuncer, Temel Engin (2014-09-05)
Semidefinite relaxation (SDR) is a powerful approach to solve nonconvex optimization problems involving rank condition. However its performance becomes unacceptable for certain cases. In this paper, a nonconvex equivalent formulation without the rank condition is presented for the broadcast beamforming problem. This new formulation is exploited to obtain an alternating optimization method which is shown to converge to the local optimum rank one solution. Proposed method opens up new possibilities in differe...
Low-Complexity Iterative Channel Estimation and Tracking for Time-Varying Multi-Antenna Systems
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The iterative channel estimation and tracking problem is considered for time-varying frequency-flat fading multiinput multi-output (MIMO) systems. In order to jointly estimate and track the time-varying multi-antenna channel, the pilot symbol assisted modulation (PSAM) technique is generalized to the multi-antenna systems. By distributing the pilot symbols along the transmitted block, i.e., PSAM transmission, the proposed system gains the ability to track the channel variation with the same amount of pilots...
Citation Formats
Ö. T. Demir and T. E. Tuncer, “Iterative Rank Minimization For Broadcast Beamforming,” 2014, Accessed: 00, 2020. [Online]. Available: