General research interests are the applications of signal processing and optimization theories to data communications, machine learning and big data analysis.

My Google Scholar profile

Selected Publications

(1) Distributed Optimization/Optimization for Machine Learning

10. Z. Wang, J. Zhang, J. Li, T.-H. Chang, Z.-Q. Luo, "Distribtued stochastic consensus optimization with momentum for non-convex non-smooth problems," submitted for publication, 2020.

9. S. Wang and T.-H. Chang, "Federated matrix factorization: Algorithm design and application to data clustering," submitted for publication, 2020.

8. S. Wang, T.-H. Chang, Y. Cui and J.-S. Pang, "Clustering by orthogonal NMF model and non-convex penalty optimization," submitted for publication, 2020.

7. T.-H. Chang*, M. Hong*, H.-T. Wai*, X. Zhang and S, Lu, "Distributed learning in the non-convex world: From batch to streaming data and beyond," IEEE Signal Process. Mag., 2020 (* equal contribution)

6. M. Hong and T. -H. Chang, “ Stochastic Proximal Gradient Consensus Over Random Networks," IEEE Trans. Signal Process., vol. 65, no. 11, pp. 2933-2948, June 2017. 

5. T.-H. Chang," A proximal dual consensus ADMM method for multi-agent constrained optimization ", IEEE Trans. Signal Process., vol. 64, no. 14, pp. 3719-3734, July 2016.

4. T.-H. Chang, W.-C. Liao, M. Hong and X. Wang," Asynchronous Distributed ADMM for Large-Scale Optimization PartII: Linear Convergence Analysis and Numerical Performance ", IEEE Trans. Signal Process., vol. 64, no. 12, pp. 3131-3144, June 2016.

3. T.-H. Chang, M. Hong, W.-C. Liao and X. Wang," Asynchronous Distributed ADMM for Large-Scale Optimization- Part I: Algorithm and Convergence Analysis,” IEEE Trans. Signal Process., vol. 64, no. 12, pp. 3118-3130, June 2016.

2. T.-H. Chang, M. Hong and X. Wang," Multi-agent distributed optimization via inexact consensus ADMM ”, IEEE Trans. Signal Process., vol. 63, no. 2, pp. 482-497, Jan. 2015.  (2021 IEEE SPS Best Paper Award, ESI Highly Cited Paper) 

1. T.-H. Chang, A. Nedich, and A. Scaglione," Distributed constrained optimization by consensus-based primal-dual perturbation method ”, IEEE Trans. Automatic Control, vol. 59, no. 6, pp. 1524-1538, June 2014.  (ESI Highly Cited Paper) 

(2) UAV Communications

3. L. Li, T.-H. Chang and S. Cai, "UAV Positioning and Power Control for Two-Way Wireless Relaying," IEEE Trans. Wireless Commun., vol. 19, no. 2, 1008-1024, Feb. 2020.

2. C. Shen, T.-H. Chang, J. Gong, Y. Zeng and R. Zhang," Multi-UAV Interference Coordiation via Joint Trajectory and Power Control," IEEE Trans. Signal Process., vol. 68, pp. 843-858, Jan. 2020

1. Jie Gong, T. -H. Chang, Chao Shen and Xiang Chen, “ Flight Time Minimization of UAV for Data Collection over Wireless Sensor Networks," IEEE J. Sel. Area Commun. , vol. 36, no. 10, 1-13, Oct. 2018.   (ESI Highly Cited Paper) 

(3) Transmit Beamforming Optimization

6. M. Zhu, T. -H. Chang, and M. Hong, "Learning to beamform in heterogeneous massive MIMO networks," submitted for publication, 2020.

5. T.-H. Chang, Y.-F. Liu and S.-C. Lin, “ QoS-Based Linear Transceiver Optimization for Full Duplex Multi-User Communications,” IEEE Trans. Signal Process., vol. 66, no. 9, pp. 2300-2313, May. 2018. 

4. K.-Y. Wang, A. M.-C. So, T.-H. Chang, W.-K. Ma and C.-Y. Chi," Outage constrained robust transmit optimization for multiuser MISO downlinks: Tractable approximations by conic optimization ", IEEE Trans. Signal Process., vol. 62, no. 21, pp. 5690-5705, Nov. 2014. (2018 IEEE SPS Best Paper Award, ESI Highly Cited Paper)

3. W.-C.Li, T.-H. Chang, Che Lin and C.-Y.Chi," Coordinated beamforming for multiuser MISO interference channel under rate outage constraints ", IEEE Trans. Signal Process., vol. 61, no. 5, pp. 1087-1103, March 2013.

2. C. Shen, T. -H. Chang, K. -Y. Wang, Zhengding Qiu and C. -Y. Chi, " Distributed robust multicell coordinated beamforming with imperfect CSI: An ADMM approach," IEEE Trans. Signal Process. , vol. 60. no. 6, pp. 2988-3003, June 2012.

1. T.-H. Chang, Z.-Q. Luo and C.-Y. Chi," Approximation bounds for semidefinite relaxation of Max-Min-Fair multicast transmit beamforming problem ", IEEE Trans. Signal Process., vol. 56, no. 8, pp. 3932-3943, August 2008.

(4) Physical-Layer Security

1. W.-C. Liao, T.-H. Chang, W.-K. Ma, and C.-Y. Chi," QoS-based transmit beamforming in the presence of eavesdroppers: Anoptimized artificial-noise-aided approach ", IEEETrans. Signal Process., vol. 59, no. 3, pp. 1202-1216, March 2011.  (ESI Highly Cited Paper)

2. T.-H. Chang, W.-C. Chiang, Y.-W. Peter Hong, and C.-Y. Chi," Training sequence design for discriminatory channel estimation in wireless MIMO systems ", IEEE Trans. Signal Process., vol. 58, no. 12, pp. 6223-6237, Dec. 2010.

(5) Smart Grid Control

1. S.-C. Tsai, Y.-H. Tseng and T.-H. Chang, " Communication-efficient distributed demand response: A randomized ADMM approach,” IEEE Trans. Smart Grid, vol. 8, no. 3, pp. 10851095, May 2017.

2. T.-H. Chang, M. Alizadeh, and A. Scaglione," Real-time power balancing via decentralized coordinated home energy scheduling ", IEEE Trans. Smart Grid, vol. 4, no. 3, pp. 1490-1504, Sept. 2013.