| Presentation | 2016-07-21 Estimation for the number of collision packets in the space-based AIS Takanori Kanzawa, Kazuhiko Fukawa, Daichi Hirahara, |
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| PDF Download Page |  PDF download Page Link |
| Abstract(in Japanese) | (See Japanese page) |
| Abstract(in English) | Automatic Identification System (AIS) information can be obtained across the open sea by the space-based AIS. In Japan, JAXA has conducted a space-based AIS experiment, which is called space-based AIS experiment (SPAISE). In this experiment, satellites equipped with AIS receivers have been launched to altitude 600km and receive AIS signals suffering from Doppler shift. The experiment results clarify that the wide coverage of the satellite causes collision of many AIS signal packets, which makes signal detection very hard. In order to estimate the number of collision packets for separating and detecting the collision packets, this report proposes an estimation method exploiting correlation between received signals and the training sequence. The phase of the training sequence is rotated by candidates of the Doppler frequency and then received timing is delayed by candidates of delayed time. Then, the correlation between the resultant training sequences and the received signals is calculated. By searching for the highest peak of the correlation, we can estimate the Doppler frequency and delayed time of the dominant AIS packet. The training sequence with the estimated Doppler frequency and delayed time is subtracted from the received signals. The correlation between the resultant received signals and training sequence is calculated again. These processes are repeated until the peak of the correlation does not exceed a threshold, which can estimate the number of collision packets. Computer simulations evaluate mean squared estimation errors of the Doppler frequency, the delay time, and the complex envelope, and show that when the average received power of each packet is equal, how the error rate of the number of collision packets depends on the average signal to noise ratio. Especially, it is demonstrated that the error detection rate becomes approximately 45% when the number of collision packets is 4, 20 % for 3, and 5% for 2. |
| Keyword(in Japanese) | (See Japanese page) |
| Keyword(in English) | Automatic Identification System (AIS) / SPAISE / collision packet number / correlation detection |
| Paper # | SAT2016-20 |
| Date of Issue | 2016-07-14 (SAT) |
| Conference Information | |
| Committee | AP / SAT / SANE |
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| Conference Date | 2016/7/20(3days) |
| Place (in Japanese) | (See Japanese page) |
| Place (in English) | Otaru port marina |
| Topics (in Japanese) | (See Japanese page) |
| Topics (in English) | Remote sensing, Radio propagation, Antennas and Propagation, Sattelite Communication |
| Chair | Keizo Cho(Chiba Inst. of Tech.) / Takatoshi Sugiyama(Kogakuin Univ.) / Hirokazu Kobayashi(Osaka Inst. of Tech.) |
| Vice Chair | Hisato Iwai(Doshisha Univ.) / Toshinori Susuki(Tohoku Gakuin Univ.) / Hiroyuki Tsuji(NICT) / Takahide Mizuno(JAXA) / Toshifumi Moriyama(Nagasaki Univ.) |
| Secretary | Hisato Iwai(Niigata Univ.) / Toshinori Susuki(NTT DoCoMo) / Hiroyuki Tsuji(NTT) / Takahide Mizuno(KDDI R&D Labs.) / Toshifumi Moriyama(JAXA) |
| Assistant | Nobuyasu Takemura(Nippon Inst. of Tech.) / / Atsushi Kezuka(ENRI) / Manabu Akita(Univ. of Electro-Comm.) |
| Paper Information | |
| Registration To | Technical Committee on Antennas and Propagation / Technical Committee on Satellite Telecommunications / Technical Committee on Space, Aeronautical and Navigational Electronics |
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| Language | JPN |
| Title (in Japanese) | (See Japanese page) |
| Sub Title (in Japanese) | (See Japanese page) |
| Title (in English) | Estimation for the number of collision packets in the space-based AIS |
| Sub Title (in English) | |
| Keyword(1) | Automatic Identification System (AIS) |
| Keyword(2) | SPAISE |
| Keyword(3) | collision packet number |
| Keyword(4) | correlation detection |
| 1st Author's Name | Takanori Kanzawa |
| 1st Author's Affiliation | Tokyo Institute of Technology(TokyoTech) |
| 2nd Author's Name | Kazuhiko Fukawa |
| 2nd Author's Affiliation | Tokyo Institute of Technology(TokyoTech) |
| 3rd Author's Name | Daichi Hirahara |
| 3rd Author's Affiliation | Japan Aerospace Exploration Agency(JAXA) |
| Date | 2016-07-21 |
| Paper # | SAT2016-20 |
| Volume (vol) | vol.116 |
| Number (no) | SAT-144 |
| Page | pp.pp.51-56(SAT), |
| #Pages | 6 |
| Date of Issue | 2016-07-14 (SAT) |