PMID- 19731399 OWN - NLM STAT- MEDLINE DCOM- 20091006 LR - 20191210 IS - 0129-0657 (Print) IS - 0129-0657 (Linking) VI - 19 IP - 4 DP - 2009 Aug TI - A fully complex-valued radial basis function network and its learning algorithm. PG - 253-67 AB - In this paper, a fully complex-valued radial basis function (FC-RBF) network with a fully complex-valued activation function has been proposed, and its complex-valued gradient descent learning algorithm has been developed. The fully complex activation function, sech(.) of the proposed network, satisfies all the properties needed for a complex-valued activation function and has Gaussian-like characteristics. It maps C(n) --> C, unlike the existing activation functions of complex-valued RBF network that maps C(n) --> R. Since the performance of the complex-RBF network depends on the number of neurons and initialization of network parameters, we propose a K-means clustering based neuron selection and center initialization scheme. First, we present a study on convergence using complex XOR problem. Next, we present a synthetic function approximation problem and the two-spiral classification problem. Finally, we present the results for two practical applications, viz., a non-minimum phase equalization and an adaptive beam-forming problem. The performance of the network was compared with other well-known complex-valued RBF networks available in literature, viz., split-complex CRBF, CMRAN and the CELM. The results indicate that the proposed fully complex-valued network has better convergence, approximation and classification ability. FAU - Savitha, R AU - Savitha R AD - School of Electrical and Electronics Engineering, Nanyang Technological University, Singapore. FAU - Suresh, S AU - Suresh S FAU - Sundararajan, N AU - Sundararajan N LA - eng PT - Journal Article PL - Singapore TA - Int J Neural Syst JT - International journal of neural systems JID - 9100527 SB - IM MH - *Algorithms MH - *Artificial Intelligence MH - Humans MH - *Neural Networks, Computer MH - Signal Processing, Computer-Assisted EDAT- 2009/09/05 06:00 MHDA- 2009/10/07 06:00 CRDT- 2009/09/05 06:00 PHST- 2009/09/05 06:00 [entrez] PHST- 2009/09/05 06:00 [pubmed] PHST- 2009/10/07 06:00 [medline] AID - S0129065709002026 [pii] AID - 10.1142/S0129065709002026 [doi] PST - ppublish SO - Int J Neural Syst. 2009 Aug;19(4):253-67. doi: 10.1142/S0129065709002026.