# Projects

### Information Geometry and Applications

I am currently studying Information Geometry under supervision of professor Sueli Costa at the Institute of Mathematics, Statistics and Scientific Computing (IMECC), Unicamp. Information Geometry consists in studying the intrinsic geometry of probability distributions — regarded as Riemannian manifolds — using the tools from differential geometry. We aim to apply these techniques to problems in signal processing and machine learning.

### Context-tree-based compression for CSI feedback (more)

We propose a novel context-tree-based approach to compressing time-varying CSI for wireless communications. The proposed scheme combines lossy vector quantisation, by means of data-adapted companders, with lossless compression, based on symbol probabilities estimated by a context-tree model.

This project was developped under supervision of professor Sheng Yang, at the Laboratory of Signals and Systems (L2S), CentraleSupélec.

##### Preprint

- H.K. Miyamoto and S. Yang. “Context-Tree-Based Lossy Compression and Its Application to CSI Representation”.
*arXiv:2110.14748*, 2021.

### Spherical Codes by Hopf Foliations

Spherical codes are discrete sets of points on the surface of an Euclidean sphere, and have several applications in sicences and engineering. Problems with spherical codes involve finding optimal distributions of points relative to some parameter of interest (such as minimum distane between the points). We address the spherical packing problem by exploiting Hopf foliations in dimensions 2ᵏ, which yields a constructive method for spherical codes in such dimensions, for a given minimum distance.

This scientific initiation project was developped from 2016 to 2018 at the Institute of Mathematics, Statistics and Scientific Computing (IMECC), Unicamp, under supervision of professors Henrique Sá Earp and Sueli Costa. The project was supported by FAPESP as part of the thematic project
*Security and reliability of information: theory and practice* of which professor Costa was one of the main researchers.

##### Journal paper

- H.K. Miyamoto, S.I.R. Costa and H.N. Sá Earp. “Constructive spherical codes by Hopf foliations”.
*IEEE Transactions on Information Theory (Early Access)*, 2021. arXiv:2008.10728

##### Conference papers

- H.K. Miyamoto, H.N. Sá Earp and S.I.R. Costa, “Constructive spherical codes in 2ᵏ dimensions”.
*IEEE International Symposium on Information Theory (ISIT)*. Paris, 2019. doi: 10.1109/ISIT.2019.8849464. - H.K. Miyamoto, H.N. Sá Earp and S.I.R. Costa, “Construção de códigos esféricos usando a fibração de Hopf”.
*National Journey of Scientific Initiation (JNIC), 70th Annual SBPC Meeting*, UFAL, Maceió, 2018. Anais: resumos da 70ª Reunião Anual da SBPC. São Paulo: SBPC, 2018. ISSN: 2176-1221. (in Portuguese) - H.K. Miyamoto, H.N. Sá Earp and S.I.R. Costa, Construção de códigos esféricos usando a fibração de Hopf.
*Journey of Mathematics, Applied Mathematics and Mathematical Education (J3M)*. UFPR, Curitiba, 2017. (in Portuguese) - H.K. Miyamoto, H.N. Sá Earp and S.I.R. Costa, “Construction of spherical codes using the Hopf fibration”.
*XXV Unicamp Congress of Scientific Initiation*, Unicamp/Campinas, 2017. Campinas: Galoá, 2018. doi: 10.19146/pibic-2017-78809.

##### Presentations

- Construction of spherical codes using the Hopf fibration.
*International Congress of Mathematicians (ICM)*. Short Communication. Rio de Janeiro, 2018. - A recursive algorithmic construction for spherical codes in dimensions R^{2^k}.
*Latin American Week on Coding and Information (LAWCI)*. IMECC/Unicamp, Campinas, 2018. - Construção de códigos esféricos usando a fibração de Hopf.
*DivulgaMat Seminars*. IMECC/Unicamp, Campinas, 2018. - Construção de códigos esféricos usando a fibração de Hopf.
*IEEE Day Scientific Show*. IEEE Academic Branch. FEEC/Unicamp, Campinas, 2017.

### Secondary education

During secondary education, I was mainly involved with Educational Robotics.

##### Works

- H.K. Miyamoto, A.M.R.G. Santos, F. Ferreira and I.C.V. Ferreira, “Mosaico Digital: monitor interativo de realidade aumentada”.
*Mostra Nacional de Robótica (MNR)*, Fortaleza, 2013. Anais da III Mostra Nacional de Robótica (MNR 2013). Sorocaba: Unesp, 2016. pp. 156–168 ISBN: 978-85-64992-22-1. (in Portuguese) - A.C.B. Jesus, A.M.R.G. Santos, G.R. Alves, H.K. Miyamoto, I.J.M.M.T. Matos, L.C.L. Vasconcellos, I. Valverde and F. Ferreira, “Projeto Soccer: desenvolvimento de robôs cooperativos baseado na modalidade Soccer B da RoboCup Junior”.
*Mostra Nacional de Robótica (MNR)*, Fortaleza, 2012. Anais da II Mostra Nacional de Robótica (MNR 2012). Sorocaba: Unesp, 2016. pp. 190–196. ISBN 978-85-64992-23-8. (in Portuguese)