Improvement of high‐voltage impulses in track circuits with Kasami and LS codes |
| |
| Authors: | Lei Yuan Yuan Yang Álvaro Hernández |
| |
| Affiliation: | 1. Electronics Department, Xi'an University of Technology, Xi'an, Shaanxi, China;2. Electronics Department, University of Alcala, Alcalá de Henares, Madrid, Spain |
| |
| Abstract: | Track circuit systems based on high‐voltage impulses (HVI) have already been used in China to detect the state of track sections. With the demand for more reliable intelligent transportation systems in recent years, new advances, improvements, and innovations are being applied to their development. This work defines a HVI track circuit based on the encoding of the transmitted signal. Not only 15‐bit and 63‐bit Kasami sequences but also 19‐bit and 71‐bit loosely synchronized codes are applied to encode simultaneous HVI transmissions from 2 emitters. Train occupancy in different parts of the track section is also considered. The quality of the detection is evaluated by means of the correlation bounds. Furthermore, a simulation model for double‐track railways has been developed, which can be dedicated to the evaluation of a suitable signal processing in the track circuit under study. Compared to previous HVI track circuits, as a novelty, this work proposes the use of encoded transmissions to these track circuits, to improve their performance in terms of scanned distance and detection accuracy. The correlation properties of the sequences involved also make feasible to avoid any synchronization link between emitters and receivers, thus providing a significant advantage for later deployment. |
| |
| Keywords: | high‐voltage impulse (HVI) Kasami sequences loosely synchronized (LS) code signal processing track circuit track simulation model |
|
|
