by Iván Darío Quintero
Perhaps, one of the most surprising developments that we are witnessing today is that of wireless communications and its close relationship with automation, which apparently ended up not allowing us to get out of bed again.
But, exactly in the segments of alarms and CCTV the impact of wireless communication has revolutionized the ways of working and the ways of assuming the business, since in the security market thanks to wireless communications the cable turns out to be an unnecessary risk.
The creation of all kinds of devices suitable for working on technologies such as wireless, GSM / GPRS or WiFi, have allowed the migration to wireless to be fast but a little confusing.
The fact of not having cables for transmission is the most relevant point for wireless transmissions to be the most accepted, at least in facilities of several kilometers, as is the case of citizen security systems.
Currently, almost all cities in the world have citizen security systems, but approaching a case study will always be a good way to know how they are acting in this regard in another place in the region and what is the current situation on the subject, either as a reference for other CCTV applications or citizen security systems.
Case Study
In Colombia, the city of Tulúa has always been a strategic place in the center of Valle del Cauca, a department located in the west of the country. At present, this town is one of the most important in the country, being located, despite not being capital, among the twenty most important and outstanding cities.
Precisely, there the installation of a CCTV with IP cameras was carried out and a whole support was elaborated so that the IP system worked wirelessly.
In the assembly, BOSH G4 autodome IP cameras were used, for the transmission the Motorola Canopy solution was used and in the central the Vidos control software was also manufactured by Bosh, this software allows the control, administration and visualization of the entire system.
Practically the only thing that was used there, and that was not manufactured by Bosh, was the Canopy communication system, which is owned by Motorola, another modern solution that was added to this advanced assembly in the Colombian city. Canopy allows you to make point-to-point, point-to-multipoint or backbone connections for a metropolitan WiFi network.
Since most of the equipment used there was manufactured by Bosh, we contacted Miguel Baquero, the engineer in charge of the company's projects, to illustrate this.
Specifically, what was done in the city of Tulúa was to set up a wireless network to transmit video signals in an IP way and in digital form to the control center, to be able to visualize and record completely IP there.
Among what was taken into account to use this system is also the fact that there are no cables, which gives the system more security features and cost savings, since analog transmission systems are much more expensive than IP systems, In addition, for analog transmission systems point-to-point transfer is required, while for IP it is not necessary.
Precisely this is the main contribution of the TCP /IP transmission system combined with the Canopy wireless transmission system, since it was not necessary to carry out a point-to-point communication, simply the signal is sent from the camera to the nearest link, as the engineer put it: "you can mount a backbone out there and collect all the signals and then send them to the monitoring center, in this case some of the cameras are mounted that way and others are not." "When you assemble an analog system, the wireless transmission has to be point to point, that is, I have to have a transmitter and a receiver for each of the cameras, I can't multiplex the video signals, I can't carry several signals through the same transmitter or through a central point, being analogous they require a transmission and receiving pair, which makes it not very functional for very long distances where the link does not give me the distance I require." This is what Baquero said.
All the features mentioned by Baquero for analog communication become virtues when implementing a citizen security system supported in TCP / IP, communication does not have to be point to point and video signals can be multiplexed.
The entire installation was done with Bosh generation four IP autodome cameras, and an average of thirty cameras were installed throughout the city. The reception and viewing and recording system are also totally IP, their location was kept in reserve because the entire system is managed by the police of the place and they preferred it to be so.
Already in the control center there are antennas that receive and lower the signals to a network, they are connected to a local swtich and there the PCs are connected with the visualization software, the joysticks for control of the cameras are connected to the PCs and the recording is done on a server with NVR software .
When we asked engineer Baquero about the characteristics of the recording system, such as the maximum time of the system recording continuously, or the compression format of the image, he did not want to go into details because the police prefer to keep many of the features secret, however, he told us that in these citizen security solutions recording systems are usually used that could record for a month or more.
On the other hand, the operators of the monitoring center, who are the policemen themselves, operate the cameras in what is known as a virtual matrix system, which thanks to the Vidos software allows the operator to choose any camera on the screen and with the joystick operate any of the equipment installed in the city to do for example pans and zooms , in the same way, as the cameras are not many, the system allows to have the 30 cameras at the same time on the screen.
Something that makes Bosh cameras very special is that these devices are modular and at any time parts can be replaced, that is, these devices can be updated without having to change the entire camera. "For example, if the cameras have a specific zoom , to say the least, 18 or 16 x and you want to have a larger zoom in these places, it would simply be to change the zoom module, without having to change or disassemble the entire camera; if for any reason, the camera requires some maintenance or suffers any damage, simply change one of the modules, the module that is damaged. It is not required that the camera goes to service, as the modules are sealed units is simply to replace them, which greatly facilitates the issue of maintenance, which is one of the most important issues in city monitoring, "explained Baquero.
Most problems in the cameras are very simple, but the issue of lowering the cameras, taking them to the service center, having authorized personnel do the repair, etc., makes these processes very cumbersome and wasteful; Bosh cameras can be changed parts, complete parts, in addition this replacement of parts can be done by personnel with an average rating, an installation technician can make a change and make the camera work without having to take it to the service center.
The fact that bosh domes are completely modular gives them another interesting advantage, this is that with the same G4 dome you can make an analog or IP installation, simply varies a module, the connection, "then it is very simple, and if for example a city today mounted an analog system and wanted in a year or six months to change it to IP, would simply change the module that comes internal in the camera without having to change the entire camera or the system" said the engineer. Bosh G4 cameras typically use 26 x and 36 x zoom , and can rotate 360º, with an 18º view of the horizon above zero.
Combination with the 123 emergency system
With the implementation of this project it was sought to provide more security to citizens, as is happening in other cities of the world, there was also installed in the same place the unique emergency system 123, they are not the same operators, but the idea is that they can support each other, so if someone reports an illicit act on the phone, the team will be able to verify through the video system, or vice versa, if an accident is seen through the cameras, they can send an ambulance or the police themselves to the place of the event.
