Casco signaling systems have been a common occurrence.

Absrtact: November 1, the Shenzhen subway Shekou line multiple train failed to suspend operation. 5th, the same scene again in the snake Mouth line again; 7th, the Shenzhen Metro ring centerline also due to the same reasons for the failure, the cause of the accident initially locked into a portable WiFi signal interference.

November 1, the Shenzhen subway Shekou line A number of trains failed to suspend operation. 5th, the same scene again in the snake Mouth line again; 7th, the Shenzhen Metro ring centerline also due to the same reasons for the failure, the cause of the accident initially locked into a portable WiFi signal interference. November 9, Shenzhen Metro Group finally issued a notice, admitted before the snake Mouth line and the center of the ring is affected by the WiFi signal caused by the failure. The signal maker Casco, the two lines, has also been pushed to the forefront.

Casco Company yesterday, the interference incident is not caused by signaling system failure, there is no systematic design flaws. This is a new issue arising from the development of information technology and the application of results. Shenzhen Metro Group Party construction Minister Wang Yuzhu said that these days did not receive any reports of signal failure. "Casco cooperated with us in the signal system rectification, has taken effective measures." I also ask the public to rest assured why our subway is operating as usual after the disturbances occur. Because the interference incident only caused delay, the subway safety is within our control.

Casco is a supplier of Wenzhou-Ningbo accident train

Casco Signal Co., Ltd. was founded in March 14, 1986, is by the China Railway Communication Signal Group and Alstom (China) Investment Co., Ltd. was formed, is the first Sino-foreign joint ventures.

The company is one of the suppliers of the "7 23-yong train accident" and a signal producer of the Shanghai subway crash last year.

According to the new century, July 29, 2011 afternoon, the operator of Shanghai Subway Company announced the results of the survey, Shanghai Metro line Line 10 implementation of CBTC (wireless communication based signal control system) signal upgrade and debugging, the information blocking failure, The latter train repeatedly used a route signal to the Hongqiao train station, with two trains rear-end.

The accident, which caused more than 270 passengers to be injured, raised doubts about the Casco company's CBTC signaling system, and the instability of its signalling system was also noted by customers and experts.

In addition to these mega-traffic accidents, Casco signaling system failures have been common, but did not prevent the company to win more City Subway signaling system contract. Shenzhen subway Shekou line, Ring midline is also part of it, it is reported that Casco company in the construction of Shekou signaling system also set a record of the shortest duration.

The company says it has taken steps with the subway

South all reporters contacted Casco company Shanghai Headquarters Marketing Department deputy public Relations manager Zhang Chengji, in an interview, she answered the current Casco company's many questions. "The incident was stated in an official statement issued by the Shenzhen Metro Group in Friday, and it is clear that the incident was not caused by a signaling malfunction or a system design flaw," Ms. Zhang said. This is a new issue arising from the development of information technology and the application of results. ”

On the question of the design of the Casco signaling system, Miss Zhang replied: "The signaling system provided by Casco has been designed to take into account interference handling, and adopted the industry's latest anti-jamming technology, which is widely used in some CBTC projects in the world as well as in other cities such as Beijing and Shanghai, Robustness in coping with interference management (refers to the ability of the software to handle input outside the specification requirements). has been amply demonstrated and there have been no similar incidents of interference to date. ”

At the same time, she stressed that the Casco company has already taken effective preventive measures with the Shenzhen Metro Group for the reasons of interference. After the implementation of the above measures, so far no similar interference incidents occurred.

Questions

Why the Longhua line and the Longgang line are unharmed

The Shenzhen Shekou line and the central midline have been suffering from WiFi interference. In Friday, Shenzhen Metro Group said that after in-depth analysis and testing, the primary reason for the failure is that the line signaling system was caused by the signal interference from the portable 3G wireless router used by passengers on the train (the principle is different from the 3G mobile phone itself WiFi function). This kind of portable 3G wireless router is mainly used to convert wireless communication 3G signal to WiFi signal for wireless terminal use, its wireless data transmission frequency band and subway signal system transmission frequency band is same, all is the public free frequency band 2.4GHz.

In fact, the Shenzhen subway has three construction parties, in addition to the Shenzhen Metro Group, there are Shenzhen Metro line Line 3 Investment Co., Ltd. and the MTR. Why the original Shenzhen Subway group construction line suffers from WiFi interference, other routes are not this worry? Shenzhen Metro Group and signal contractor Casco remain in doubt.

1

Lobo Line and Longhua line Phase I system older than the frequency band

Lobo Line and Longhua Line are the first phase of Shenzhen Metro project. According to Shenzhen Subway insiders, as well as the relevant public information, these two companies use a quasi-mobile block system in signalling systems, unlike the mobile Block system (CBTC), which is currently problematic, which does not need to be used in frequency bands and therefore does not involve the problem of WiFi interference.

2

Two Hong Kong iron use fee band for Longhua Line

But on the train, in addition to the signaling system, there are passenger information systems (PIDs), that is, television on the train.

Public information shows that the passenger information system operated by the Hong Kong Railway (Shenzhen) is the use of wireless network transmission, but the MTR has not used the 2.4GHz frequency band without the need to apply for fee, but has used the 5.8GHz frequency bands which require application and payment.

Shenzhen subway insiders revealed that the two-phase construction of Longhua line is the Hong Kong Railway, the MTR at that time to take into account the Longhua line in part of the road on the pavement, to be subject to greater interference, and taking into account the 5.8GHz band has a strong commercial potential, so the choice of this frequency band.

Although the industry has revealed that, from the radio development trend, 5.8GHZ is likely to soon open up, as no need to apply for fee-free band. However, the Shenzhen subway insiders have to admit that, in the Shenzhen subway Shekou line ring signal interference today, the choice of MTR is more forward-looking.

Public information shows that some of the MTR lines also use mobile block systems (CBTC), which require the use of wireless networks to transmit signals. The Hong Kong Railway Corporation (MTR) said that its WiFi services were under the supervision of relevant government departments and that the MTR Corporation had stringent measures to ensure that WiFi services provided by service providers would not affect the operation of the railway services.

Liu Chongming, associate professor of electronic and consulting engineering at the Hong Kong Polytechnic University, said that it is possible to interfere with each other if the WiFi used by the passengers and the subway signaling system is in the 2.4GHz band. However, at present, the use of passenger WiFi in this common frequency band, the MTR is not the common frequency band, so there is no interference with each other.

3

Longgang Line uses Bombardier system

The Longgang line is mostly on the ground, but there are still tunnel works. It is reported that the three major communications operators also installed in the tunnel related signal transmitters.

But the Longgang line says that in practice and in recent tests, the Longgang line signaling system has not been disturbed by WiFi.

The principle of the Longgang line signaling system is the same as that of the snake and ring lines, using a moving block signal. But the contractor is not the same, the Longgang line for Bombardier Systems, Shekou and the center of the Ring line is the CASCO system.