@article{CTT100681806,
  author = {N. Thong-un and S. Hirata and M. K. Kurosawa},
  title = {Three-dimensional-positioning based on echolocation using a simple iterative method},
  journal = {AEU - International Journal of Electronics and Communications},
  year = 2014,
}

@article{CTT100743996,
  author = {N. Thong-un and M. K. Kurosawa},
  title = {Doppler velocity estimation of overlapping linear-period-modulated ultrasonic waves based on an expectation-maximization algorithm},
  journal = {Advanced in Acoustics and Vibration},
  year = 2014,
}

@inproceedings{CTT100681045,
  author = {N. Thong-un and M. K. Kurosawa and S. Hirata},
  title = {Examination of three-dimensi onal airborne ultrasonic position real-time measurement using chirp wave},
  booktitle = {Proceedings of Symposium on Ultrasonic Electronics},
  year = 2014,
}

@inproceedings{CTT100681043,
  author = {Natee Thong-un and yuichiro orino and Minoru K Kurosawa and Shinnosuke Hirata},
  title = {Three-dimensional-positioning measurements based on echolocation using linear-period-modulated ultrasonic signal},
  booktitle = {},
  year = 2014,
}