WiFi signal or interference in the subway system: Metro WiFi has to wait, etc.

At the end of last year, Guangzhou Metro and a Shenzhen company set up a joint venture to study the coverage of WiFi in the subway. At that time, the person in charge of the Shenzhen enterprise said that in July this year, it will give priority to the trial of three or four lines with dense crowds, and it will be fully open next year. But now it is at the end of August, there is still no line that can use WiFi. Guangzhou Metro said that it did not say that WiFi will be opened this year.

Domestic subway WiFi opening time

Shenzhen July 2014

Changsha September 2014

Kunming December 2014

Shanghai June 2015

Guangzhou Metro: I have not said that WiFi will be opened this year.

The fastest annual coverage in Tianjin, Wuhan and Dalian

At the end of December last year, Zhou Nan, chairman of Shenzhen Southern Silver Valley, said in an interview with the media that the company had established a joint venture with Guangzhou Metro a month ago and obtained exclusive access to WiFi for 15 years in Guangzhou's 10 subway lines.

It is said that three years ago, the company had conducted technical demonstrations at the three stations of Changgang, Xiaogang and Zhongda. The internal test began in the Spring Festival last year and construction began. "It is expected that in July 2015, priority will be given to the opening of three or four lines with dense crowds, and it will be fully open in 2016."

Now that it has arrived at the end of August, the reporter recently took several subway lines and found no WiFi signal. "It is a big project to realize WiFi Internet access in the subway. 'July' is just an estimate at that time. Now we are working together with the Guangzhou Metro to promote it. For the time being, there is no conditional opening." The relevant person in charge of the Southern Silver Valley responded to the reporter.

How long does it take to use WiFi in the subway? "There is no specific timetable yet. We hope to open it as soon as possible. Some news will be released soon," said the Southern Silver Valley. The Guangzhou Metro, which cooperated with it, said yesterday that it did not say that WiFi was opened this year.

What is the difficulty?

Station station is easy, it is difficult to move trains

According to the introduction of the Southern Silver Valley, the static area in the station hall is relatively good. The problem is that the tunnel is flying on the train, and the environment is very different from the ordinary underground space. The reporter learned that the free WiFi of the London Underground is an example. The available range is only on the platform. Once the train enters the tunnel, the signal will disappear.

In addition, the WiFi signal may also interfere with the signal system of the subway. In November 2012, many trains on the Shenzhen Metro Shekou Line and the Central Line were suspended, resulting in a large number of passengers being blocked. Afterwards, the Shenzhen Metro identified the cause, and the portable WiFi used by passengers disrupted the signal system of the subway.

The person in charge of the Southern Silver Valley said that the WiFi system opened in the Shenzhen Metro will use a fixed frequency band and will not pose a hidden danger to the train.

Not fast

Less than 2Mbps per person, will improve in the future

The Shenzhen Metro, which is the first to open WiFi access in China, was developed by Southern Silver Valley.

It is understood that this kind of WiFi is equipped with more than 100 megabytes of bandwidth on each train, which can guarantee more than 600 people to access the Internet at the same time. However, 100 megabytes is allocated to 600 people, each with less than 2 Mbps of bandwidth. Moreover, during the peak hours of commuting, the number of passengers in a subway can be as many as 2,000 or more, meaning that less than one-third of the people can get online.

"Metro WiFi as a new technology is constantly improving, so in the future, the speed and number of users are expected to improve compared with the present." The relevant person in charge of the Southern Silver Valley said.

Guangfo line started tender

Following the Guangzhou Metro, the Guangfo line has also launched a tender for the WLAN mobile internet application project. The relevant staff of Guangfo Metro confirmed yesterday: "After the completion of the project, the future will be able to connect to the Guangfo line."

As can be seen from the tender notice, the project scope includes the train parking lot of the platform, the station hall, the tunnel, the inside of the train and the depot.

The coverage of WiFi in the subway is becoming a trend in the domestic subway. A year ago, the Shenzhen Metro was the first to eat crabs, and Changsha Metro, Kunming Metro, and Shanghai Metro also opened WiFi Internet. Cities such as Tianjin, Wuhan and Dalian are expected to cover the fastest within the year.