张新-英语翻译

A Train Control System for Secondary Lines by Radio

Based Train Detection—COMBAT

Abstract

There has been a growing demand for a low-cost, low-maintenance signaling system on cash-strapped secondary lines. To meet this demand, we have developed the new Computer and Microwave Balise-Aided Train Control System (COMBAT). Specific features of COMBAT are the application of microwave radio balises for train detection and centralized interlocking and block functions. This paper introduces the system configuration, its basic functions, and its benefits.

Keywords: COMBAT, Train control system, Train detection, Microwave balise

1. Introduction：

Over 15 years have passed since electronic blocking systems introduced into lines with low traffic densities. As most are cash-strapped, these lines are facing difficulties in investing the large sum required to update these systems, some having either shelved modernization plan or even been compelled to retain old-fashioned non- automatic versions. In order to address this problem and provide enhancements to safety and efficiency, the development of a new low-cost train system needs to be addressed with the utmost urgency.

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In addition, track circuits are also widely used for train detection and faults of train detection resulting from rust or dirt on the surface of the rails have become a serious problem on low traffic density lines. Since track and weather conditions affect this method of train detection, it is necessary to adjust and maintain track circuits periodically with resultant increases in maintenance costs.

To solve these problems, we have developed the new, low-cost Computer and Microwave Balise-Aided Train Control System (COMBAT) for use on secondary lines .The main feature of COMBAT is to use a new train detection method that based on radio communications instead of conventional track circuits. Moreover, with regard to its interlocking and block functions, COMBAT controls trains along the entire line length by means of a centralized interlocking system. The introduction of COMBAT provides a range of benefits such as safety enhancements，improvements to traffic control efficiency, and the reductions in equipment and maintenance costs.

This paper introduces the COMBAT system configuration, its basic functions and range of benefits, and presents the results of monitored field evaluation tests.

2. Development concept：

We aimed at introducing COMBAT on low traffic density lines and developed it according to the following concepts.

To detect trains without using track circuits We aimed at achieving a solution to the

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train detection problems on low traffic density lines and train detection without using track circuits or contacting trains. Doing so would enhance safety during installation and maintenance work and reduce the related costs.

To centralize interlocking and block functions On secondary lines that are only protected by non-automatic equipment such as the tablet instrument block system, it is necessary to post traffic operations staff at each station. To make traffic control more efficient and reduce maintenance costs, we adopted a centralized interlocking system that performs interlocking and block functions at a traffic control center.

To utilize existing signaling equipment effectively Since most secondary lines are experiencing financial difficulties in terms of investment, it is necessary to minimize the renewal costs of a new train control system To this end, we aimed at achieving a train control system that as far as possible makes effective use of existing signaling equipment.

3.System configuration：

The COMBAT system configuration is shown in Fig.

COMBAT is a train control system achieved by using a centralized interlocking system of the dispersed function type. A central interlocking unit performs interlocking and block functions for the whole line. Each station on the line is equipped with an interlocking unit that controls field equipment such as signals and switches.

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Telecommunication lines, through which indication data passes, connect the center with each station.

For train detection, COMBAT uses a system composed of microwave balises (interrogators, wayside responders and on-board responders) and a train detection unit, and performs train detection by radio communications. Sets of interrogators and wayside responders installed at the home and start signal positions constitute a train detection point. Two on-board responders are installed at the front and rear of each train, each responder containing data to identify the train ID and the exact location of the responder. When a train passes a train detection point, the interrogator receives data from the on-board responders and relays it to each station's train detection unit.

4. Basic functions:

Train detection functions Dispensing with the need to have contact with the train itself, COMBAT detects a train by using point detection principles at positions where microwave balises have been installed alongside the track. To ensure that the COMBAT system's ability to detect trains is as safe as or safer than that using track circuits, a closed loop established by continuous microwave radio communications has been adopted.

The closed loop is in constant use between the interrogators and the wayside responders. A train shuts off the closed loop when it passes the detection point, and

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COMBAT detects its presence. Even if the COMBAT equipment breaks down, safety is ensured as the closed loop is also shut off to constitute a case where a train is present.

The area between two adjacent detection points is termed a detection section that corresponds to a conventional track circuit. As a train progresses along the track, the interrogator receives data from the on-board responders and the system can simultaneously identify the train from the received train data and detect the train's direction of travel from the sequence in which on-board responder data is received.

COMBAT manages each detection section according to the received data from each interrogator. A train's entry into and exit from each section are detected according to whether it has established or shut off the closed loop, the receipt of the train's ID, and the on-board responder data sequence. How the train detection sections function as a train passes is shown in these .

(1)In the first phase, when the closed loop is established at both detection points, the status of the detection section is termed \"non-presence.\"

(2 When a train enters the section, one closed loop is shut off and the status of the section is changed to unconfirmed presence.\"

(3)When the interrogator receives data from two on-board responders in the correct sequence, the system detects the train's ID and direction of travel. The section status then becomes \"confirmed presence\" and the train ID is recorded.

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(4)While a train is traveling between the detection points, the status of the section is maintained as\" confirmed presence.\"

(5)When a train passes by the other detection point and the interrogator receives data from the two on-board responders installed at the rear, the system detects that the progressing direction of the train is \"exiting.\" However, the status of the section and recorded train ID are maintained.

(6)When the closed loop is reestablished, the \"exiting\" of the train has been detected correctly. As a result, the status of the section reverts to \"non-presence\" and the train ID is canceled.

Once the train ID is recorded in the detection section, it is never canceled unless the exiting of the same train ID is detected correctly. Even if two or more IDs are recorded, only the ID of a train that is detected as having exited correctly will be canceled. Moreover, since COMBAT detects train IDs and constantly monitors the presence of trains, it can fulfill train tracking as a basic function. Therefore, the safety and reliability of train detection are enhanced.

Interlocking and block functions:

COMBAT's interlocking and block functions are achieved by a centralized interlocking system that has a central interlocking unit (CIU) at its heart and a station Interlocking terminal (SIT) at each station.

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The CIU performs interlocking between signals or between signals and switches along the entire length of the line. Since the interlocking function of the whole line is centralized by the CIU, COMBAT can provide total interlocking coverage as if it were one station and the block function between stations can be achieved by interlocking all start signals between adjacent stations. Moreover, using a system of train IDs for interlocking between stations enhances the safety of the block function.

The SIT controls signals or switches according to control data received from the CIU. To reduce data communication loads between the center and each station, the SIT has separate functions to (a) lock the switch after the completion of an operation and (b) to change the relevant signals to stop after the entry of a train on to a section of the line.

An outline of the interlocking and block functions of COMBAT is shown in these.

(1) When the CIU receives a route setting request, it checks conflicting routes. If

the requested route can be set, it transmits switch control data to the SIT.

(2) The SIT operates and locks the switches on the route according to the control

data received from the CIU, and transmits the data confirming the completion of switch control back to the CIU.

(3) The CIU receives the switch locking indication data from the SIT, and transmits

the signal control data to the SIT, which gives the signal to proceed according to the CIU control data and transmits the start signal data back to the CIU.

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(4) When a train departs and shuts off the closed loop at the start signal, the SIT

changes the start signal to stop. The CIU then locks the block between the relevant stations with the train ID transmitted from the train detection unit.

When a train arrives at the home signal of the next station, its ID is detected and transmitted to the CIU, which compares the train ID detected at the home signal with that of the train that it has block locked. If the two IDs match and the train has left the section between the stations, the block is unlocked

5．Train detection functions

Conventional track circuits use rails as part of the electric circuit for train detection and detect a train by the wheels short circuiting the rails when a train is present in the relevant section. They can only detect the \"presence\" or \"non-presence\" of a train in the detection section.

The train detection of COMBAT not only detects the \"presence or non-presence\" of a train but also specifies each train by number by receiving the train ID from the on-board responder. Moreover, It can detect the direction of entry into and exit from the detection section.

The merits of COMBAT's train detection functions are as follows.

5.1 Enhancement of safety and train detection reliability

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COMBAT's train detection function achieves continuous train monitoring by its ability to determine a train's ID and detect its direction of travel. Since it detects trains without contact via the rails and unaffected by the malfunction of shunt performance, it can also successfully detect light rolling stock. Moreover, even if a total train derailment occurs, it can still correctly pinpoint the train. The safety and reliability of the COMBAT train detection system represent significant advances over conventional systems.

Installation work safety enhancement Track circuits use rails to detect trains, so it is necessary to install such components as signal bonds or rail insulators in the track. In contrast, COMBAT uses microwave radio communications and detects a train without directly contacting it, making such components superfluous and enhancing the safety and ease of COMBAT installation work.

Equipment cost reduction COMBAT has fewer components than conventional systems and, as it uses less energy, it is not necessary to install large-capacity power supply equipment.

Maintenance cost reductions Track conditions or changes in the weather do not affect COMBAT's train detection capabilities, thus it is not necessary to adjust or maintain the system periodically. Moreover, since it is not necessary to consider shunting sensitivity either, light rolling stock can be introduced. Therefore, the COMBAT system and track maintenance costs can be reduced.

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5.2 Interlocking and block functions Conventional signaling systems carry out interlocking and block functions by interlocking devices and block equipment installed at each station. COMBAT provides the block function between stations and the interlocking function for the whole line by placing the central interlocking unit at the heart of the system.

The merits of COMBAT's interlocking and block functions are as follows.

5.3 Safety and reliability enhancements of interlocking and block functions :

COMBAT's interlocking system functions according to the rain ID detected by microwave balises. Significantly, the block between stations is safeguarded not only by the interlock between start signals but also by the lock afforded by the train ID. The safety and reliability of COMBAT's interlocking and block functions offers significant enhancements over those of conventional systems.

Traffic control efficiency Using its centralized interlocking system, COMBAT can efficiently perform remote control functions at each station along the line, negating the need to install expensive CTC equipment, and can monitor train positions and the route control status over the whole line.

Maintenance cost savings In conventional signaling systems, the functions of the interlocking device and the block equipment installed at each station are assigned to those stations. Since these functions are centralized in COMBAT's central interlocking

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unit, it can improve maintenance efficiency and reduce costs

6. Function evaluate

Monitored field evaluation test to evaluate the performance of COMBAT, after some tests were carried out indoors and at RTRI, an operational evaluation test was performed in the field. Table 1 shows a breakdown of the monitored field evaluation test.

The monitored field evaluation test was carried out for more than four years, the equipment used being shown in Figs.4 and 5. As shown in Table 2, COMBAT detected about 220,000 trains correctly in the train detection test, and controlled about 17,000 trains in the interlocking and block test.

To study the effect of train detection under different weather conditions, which has become a major problem on conventional track circuits, we carried out a weather condition test using COMBAT. In a rainfall test, we used a large-scale rainfall experiment setup, and confirmed that even a rainfall of 200 mm/h did not affect train detection performance. A long-term snowfall test conducted in a snow area also confirmed that train detection performance was not impaired. The microwave balises successfully endured wide-ranging temperatures and weather conditions throughout the entire evaluation period.

7. Conclusion

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COMBAT is a new train control system that uses radio communications for train detection and achieves total train-line control by a centralized interlocking system. During its development, we examined various aspects such as safety, reliability and costs.

Safety and reliability tests were carried out indoors and at our institute, followed by monitored field evaluation and weather condition testing, which confirmed that there were no problems. Moreover, an independent specialist committee evaluated the safety and reliability of COMBAT and confirmed it to be a system that ensures high safety and reliability , that solves the problems of electronic blocking system or track circuits, and that can improve the efficiency of installation, maintenance and traffic control.

We also calculated the typical cost of replacing a signal system with COMBAT, compared it with the cost of replacement by conventional systems, and discovered that COMBAT could be introduced at a cost 55% to 65% of that of the conventional system which consists of semi-automatic block instrument and CTC equipment.

COMBAT conforms to technical standards prevalent in Japan, and there is a will to put it into operational service. We are sure that COMBAT will greatly contribute to cost reductions and the enhancement of secondary line traffic control.

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COMBAT-基于无线列车定位的复线列车控制系统

摘 要

对于资金缺乏的铁路复线建设，一种低成本低维修率的信号系统越来越需要。为实现这一需求,我们开发了新的计算机和微波辅助应答器列车控制系统(COMBAT)。COMBAT系统的具体特征是应用微波无线电应答器进行列车定位检测和实现集中联锁和闭塞的功能。本文介绍了COMBAT系统的配置和基本功能,以及该系统的好处。

关键词:COMBAT系统；列车运行控制系统；列车定位检测；微波应答器

1 系统介绍

自从电子闭塞系统引入低密度的铁路线路已经整整过去15年。最主要原因是是财政约束,需要投入很大一笔资金来更新这些系统是这些线路面临的困难,有些线路更新改建计划暂时被搁置，甚至被迫保留使用老式的非自动化系统。为了解决这个问题和对安全性和效率的提高而开发的一种新型低成本铁路系统亟待提上日程。

此外,轨道电路也广泛用于列车定位检测，此外在低行车密度的铁路线路线上，钢轨上的铁锈或尘土对于列车定位的误差已成为一个严重的问题。由于天气情况和轨道条件对这种列车定位的影响，定期调整和维护轨道电路是必要的但结果需要增加维护成本。

为了解决这些问题,我们已经开发了新的、低成本的计算机和微波应答器辅助列车控制系统(COMBAT)在复线上使用,COMBAT主要特征是使用一种新的列车定位检测方法:基于无线电通信代替传统的轨道电路。此外,关于它的联锁和闭塞功能，COMBAT系统通过一

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个集中联锁系统CTC在整个线路长度内对列车进行控制。引入COMBAT可以提供很多好处,如安全性的提高,改善交通管制效率,减少设备和维护成本。

本文介绍了COMBAT系统配置.基本功能和使用范围,并给出了监控领域现场评估的结果。

2 发展理念

我们的目的是引进COMBAT系统在一些低密度交通线路使用和发展该系统是按照以下的思想来做的。

不使用轨道电路检测列车，我们目标是找到一个解决列车运行密度低的问题,在低密度线路列车轨道电路检测不使用或接触。这样做会提高安装和维护工作时的安全性,降低物流成本。

集中联锁闭塞性能在复线,这只是保护自动化等设备实现闭塞系统的平板仪器,有必要对交通营运人员岗位设在每个站。让交通控制更加有效率,减少维修费用,我们采用了集中联锁系统,执行联锁和闭塞功能在一个列车控制中心。

有效利用现有的信号设备,因为大多数复线正经历投资的困难,以最大限度地减少成本的新思路,更新列车控制系统来实现这个目标是必要的。我们的目标是完成一个列车控制系统,尽量做有效利用现有信号设备。

3 系统结构

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COMBAT是一种列车控制系统实现了利用集中联锁系统的分散功能类型。一个联锁装置执行联锁和闭塞功能,在铁路运营线上的每个车站都装有一个联锁装置来控制区域内的设备,如信号机和转辙机。通信线指示数据上传,可以让本车站控制中心与每一个车站都连接。

对于列车占用检测，COMBAT使用一个系统(微波应答器和车载应答器地面应答器组成)和一辆列车定位装置,并由无线电通信执行列车定位。设置查询应答器器和轨旁应答器的地方是在列车进站和列车出站信号机所在的位置，这些构成列车定位检测点。两个车载应答是安装在列车前方和后方,每个应答器所包含数据是鉴定列车的ID号码和应答器的确切位置。当一列列车经过列车检测点,查询器从车载应答和继电器收到数据然后发送到每个车站的列车检测装置。

4 基本的功能

列车检测功能执行需要有接触的列车本身,COMBAT检测列车在利用点位置检测原理的地方已经安装了微波应答器在靠近轨道边上。确保COMBAT系统检测列车的安全性比用轨道电路更加安全，因此建立了连续微波无线电通讯已被采用，它是一个闭合回路。

闭环回路是在不断的向查询应答器和轨道旁边的应答器之间传送信息。列车占用轨道后并通过轨道定位点就切断了闭环回路,以及用COMBAT系统检测它的存在。即使COMBAT设备出现故障,由于闭环回路切断安全保障能够确保,以构成一个表示状态,表明列车出现在哪个位置了。

把两个相邻检测点之间的地区被称为检测区域，它相当于一个传统的轨道电路。列车沿轨道运行,查询应答器从车载应答器接收到数据并且利用车载应答器收到的数据中的序

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列，该系统可以同时识别列车收到的数据和检测列车运行的方向。

COMBAT系统根据从每个应答器接收到的数据管理每个定位区域。列车进入和离开每个区段的检测点是根据是否已经建立或切断闭环回路,从而收到了列车的ID号和车载应答器的数据序列。当列车经过时如何检测将在下面说明。

(1)在第一阶段,当其闭环系统是建立在两个检测分区的状态,系统检测部分称其为“非占用”。

（2）当列车进入这个区域,闭环回路关闭，这个区域的状态变为“占用”的那部分。

（3）当查询应答器从两个车载应答者接收到的数据在正确的顺序,系统检测列车的ID号和运行方向。然后这个区段的状态就变成了“占用”并且列车的ID号被记录下来。

（4）当列车运行在两个监测点之间，这个区段的状态继续保持在“占用”。

（5）当列车经过了另一个监测点的同时查询应答器接收安装在后面的两个车载应答器发送的数据，这个系统检测列车离开的方向，然而这个区段的状态和列车ID号码纪录继续保持。

（6）当闭合回路重新建立,“离开”的列车已经被精确地检测到。结果,这个区段的状态回复不占用同时列车ID被取消。

一旦列车ID被纪录在检测部分,它却永远不会被取消,除非离开的是ID号码是相同的正确检测到列车。即使有两个或更多的检测系统(IDs)记录,只有列车被检测到的ID号码和离

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开的时候一样正确将被取消。此外COMBAT系统定位列车而且不断的监控列车的存在,它可以完成列车追踪的一项基本功能。因此,列车定位的安全性和可靠性检测明显提高。

联锁和闭塞功能：

COMBAT系统的联锁和闭塞功能由一个集中的联锁系统完成, 在每一个车站这个系统有一个联锁装置(CIU)在它的中心和一个车站联锁终端(SIT)。

CIU之执行沿着整个长度的铁路线路上的联锁信号机和信号机或者和信号机和转辙机。由于整个线路上联锁功能是由CIU集中控制的，COMBAT能够提供完全的联锁覆盖范围，如果一个车站的联锁闭塞功能可以在两个车站之间的所有出站信号机由联锁装备来完成。此外,使用一个列车IDS系统来提高两个车站之间安全联锁闭塞的功能。

STI根据从CIU接收到的数据来控制信号机或者转辙机。以减少控制中心和每个车站之间的数据通信负荷,SPT在道岔完成转换后有隔离锁定道岔转辙机的功能，来改变相关的信号在列车进入线路上的这个区段停止。

(1)当CIU收到进路排列要求,用它检查敌对进路。如果所要求的进路设定排列好,将传输道岔控制数据到SPT。

(2)SPT根据从CIU接收到的控制数据来操纵和锁闭道岔，并传送CIU确认的道岔控制信息回执到CIU。

(3)CIU从SPT接收道岔锁闭指示的数据,并传送信号控制数据到SPT,根据CIU控制的数据和传输开始信号的数据反馈到SPT,随后SPT给出执行开放信号。

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(4)当列车发车离开,切断出站信号机的闭环回路,SPT改变出站信号机使其停止开放。然后CIU利用由列车定位单元传输来的列车ID号码锁闭这两个相关车站之间的闭塞分区。

(5)列车到达下一个车站的进站信号机,列车的ID号码被检测并且传送到CIU,CIU比较对照列车在闭塞分区中的ID号码和列车在前一个车站的出站信号机处的ID号码。如果这两个ID号码相互匹配，列车离开两站之间的区域,然后这个闭塞分区解锁。

5.列车定位检测功能

常规的轨道电路利用钢轨作为电子电路中的一部分，通过列车的轮对短路轨道电路来检测和定位列车，当列车占据某个相关轨道区段，在这个检测区段轨道电路仅能反应列车占用和不占用。

COMBAT列车检测定位系统不仅检测列车对轨道区段的占用和非占用，而且通过从车载应答器接收到的列车ID号码数字指定每辆列车。此外，它能够检测列车进入和离开这个检测轨道区段的方向。

COMBAT列车检测定位系统的优势功能如下。

5.1增强安全性和列车检测的可靠性：

COMBAT的列车检测功能通过它的自身功能确定列车的ID号码而且检测列车的运行方向从而达到连续对列车监控。由于这个系统对列车的检测定位没有经由钢轨而且不受转轨分流的影响，它能够很成功的检测定位全部车辆。COMBAT列车检测定位系统的安全性和可靠性表现出重大的提高和改进，从而超越了常规的控制系统。

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安装布置工作中的安全性能够提高加强轨道电路利用钢轨检测列车,因此有必要在轨道上安装元件作为信号禁止钢轨绝缘。相反,COMBAT系统采用微波无线电通信和检测列车而没有直接接触钢轨,安装这些部件是多余的而且安装COMBAT可以提高安全性和易用性。

COMBAT系统的设备减少了部分组件设备，比常规系统成本大大降低，而且它利用较少的电能，所以没有必要安装大容量的电力供给装备。

维护成本降低：轨道情况或天气的变化不影响COMBAT的检测能力,从而没有必要调整和定期系统维护。此外,由于这也没有必要去考虑调车机车灵敏度,要么,所有的车辆都可引入。因此,COMBAT系统和轨道维修成本可以降低。

5.2 联锁和闭塞功能：

常规的信号系统进行联锁和闭塞功能由安装在每个车站的联锁装置和闭塞设备执行。COMBAT由放置在系统中心的联锁单元提供两个车站之间整个线路上的联锁功能和闭塞功能。

COMBAT的联锁和闭塞优势功能如下：

5.3 联锁和闭塞功能的安全性和可靠性：

COMBAT的联锁系统功能是根据由微波应答器检测的列车ID号码，值得注意的是，两站之间的闭塞不仅是通过出站信号机之间的联锁，而且是通过列车ID号码给予的锁闭。COMBAT联锁闭塞功能的安全性和可靠性相比其他常规的控制系统有了很大的改进和提

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兰州交通大学毕业设计

高。

交通控制效率利用它的集中联锁系统，COMBAT能够有效地执行沿着一条铁路线上的每个车站之间的远程控制功能，否则需要装备昂贵的CTC调度集中设备，而且这个系统能够远程监控整条线路上的列车位置和状态。

在常规的信号系统中维护费用可以节省，联锁设备的功能和闭塞设备安装在那些被分配的车站上。由于这些功能集中在COMBAT的中心联锁单元里面，它能够提高维修效率而且减少费用。

6 性能评估

现场监控测试是为了评估COMBAT的性能，日本铁道科学研究所在室内进行了一些测验之后，一项操作评估测验在这个领域开始执行。

这个监控测验评估已经执行了超过4年的时间了，COMBAT已经在列车检测中精确地定位检测了220000辆列车，而且在联锁和闭塞测试中控制了大约17000台列车。

为了研究在不同天气情况下对列车检测定位的影响，在常规的轨道电路中气候状况成为一个主要问题，我们利用COMBAT执行一下天气状况的测试。在一个降雨量的测试中，我们利用一个大范围降雨的实验装备，来证明即使降雨量在200毫米每小时，也不会影响列车的检测性能。指挥一个长期的降雪测试在一个降雪地区也证明了列车检测性能没有受损。微波应答器也能够通过整个评估时期能够成功的适应普通的温度和天气状况。

7 结论

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兰州交通大学毕业设计

COMBAT作为一种新的列车控制系统,应用无线通信的列车检测和集中联锁系统对整条线路上列车控制，在这个发展期间，我们检查了多方面的东西，例如安全性，可靠性和费用。

在室内和我们的研究机构进行了安全性和可靠性试验,其次是监测领域评估和天气条件测试,这些证实了该系统完全没有问题。此外,的专业委员会评估了COMBAT的安全性和可靠性并确认它是一个保证高安全性、可靠性的系统,而且解决了电子闭塞系统或轨道电路的问题。可以有效的提高安装、维护及交通管制效率。

我们还计算了典型信号系统替换一个COMBAT的成本,通过计算常规系统替代新型设备价格，发现COMBAT能够以常规系统的55%到65%价格引进，该系统由半自动闭塞和CTC设备组成。

COMBAT符合在日本流行的技术标准,并且有一天将会把它放在操作服务项目中。我们确信COMBAT将极大地促进降低成本,提高复线交通管制。

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