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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 3/2019 (Jan. 21, 2019)
Chinese have built the largest antenna array. The largest in the world antenna array operating at extremely low frequencies has been constructed in China. The construction of the system called WEM (Wireless Electromagnetic Method) took 13 years. It is a part of the strategy set out in the eleventh five-year economic development plan that started in 2006. The system uses terrestrial masts to generate radio waves at very low frequencies. The waves can penetrate deep into the Earth's surface, which enables the location of valuable mineral deposits (oil and precious metals), as well as the detection of early earthquake symptoms. Military applications are also very important, especially to ensure communication with submarines that make the Chinese army the world's greatest power in this field. The grid can provide communication with submarines immersed in a depth of hundreds of meters, so not only dozens of meters as in the case of the U.S. system.
Deployment diagram for the WEM system
(source: www.eng.chinamil.com.cn)
The antenna array emits extremely low frequency (ELF) radio waves in the range of 0.1 to 300 Hz. The installation covers a total area of 3700 square kilometers. The main broadcast antenna array is a grid of interconnected lattice masts of high voltage overhead lines that extend the rectangle with sides 60 km and 80 to 100 km. Masts are connected with each other by underground cables that can conduct high-intensity currents. They produce a pulsed electromagnetic field that is the source of electromagnetic waves. Such radio waves can be transmitted over very long distances, propagating not only through the atmosphere, but also the Earth's crust over distances up to 3,500 km.
The aspect of the impact of the installation on the health of local residents is controversial. Experts estimate that the radiation emitted by the installation may affect 230 million people. A similar installation was to be built in the USA, but its construction was discontinued due to residents' protests. WHO warns that these waves can accelerate the development of cancer. However, the research conducted by scientists from the Middle Kingdom shows that even standing directly by the radiation source, the person is exposed to a power level of up to 10 W, whereas Chinese standards recognize such radiation as dangerous above 300 W.
DVB-T television and the Internet via one UTP cable. Low-voltage systems in office buildings often do not include TV antenna cables, but are usually fitted with structural cabling based on UTP cables. When some users want to connect televisions to watch DVB-T broadcasts, the lack of an RF distribution system may be a major obstacle (in many locations TV signals cannot be properly received using indoor antennas).
A unique solution to this problem is to use SIGNAL TV-LAN baluns for TV over UTP, R94200. The pair of the passive baluns can transmit analog/digital RF signals from an antenna placed in a suitable place via the existing UTP cable. The transmission is performed in parallel to the "normal" use of the cable for data transmission (LAN, Internet). The idea of using the Signal TV-LAN baluns is presented in the figure below.
Baluns for TV over UTP: Signal TV-LAN (2 pcs)
Transmission of DVB-T and Ethernet signals over a single UTP cable
with the use of R94200 baluns
Although the solution is based on point-to-point connection, it is possible to use multiple transmitter-receiver kits, even in combination with TV splitters and network switches. When the RF signal level after splitting is sufficient for further distribution, the signal can be sent over another UTP cable segment after a network switch, using TV splitter and additional pair of the baluns.
Baluns for TV over UTP: Signal TV-LAN (2 pcs)
View of the baluns (visible LAN and RF connectors)
Solutions based on the baluns are much more economical in comparison with deployment of additional systems based on coaxial cables or IPTV technology (the latter also requires extra network resources). They do not convert the original RF signals, only change the transmission medium.
"Enhanced IP" mode in DVRs. Hikvision Turbo HD 4.0 DVRs with analog channels (HD-TVI 4.0) have a special mode for enhanced support of IP cameras. Normally, they can support a number of IP cameras and the possibility to replace any analog channels by IP channels. By running the enhanced IP mode, the user can further extend the number of IP channels. The maximum number is available after switching off all analog channels and depends on the DVR model and the number of its analog channels (n). It can be calculated based on formulas in the table below (in brackets - the maximum resolution of IP cameras):
9000n/2+n (6MP)n+n (12MP)-
8100n/2+n (6MP)--
7300n/2+n (6MP)n+n (8MP)n+n (8MP)
7200n/2+n (6MP)n+n (8MP)-
7100n/2+n (6MP)n+n (8MP)-
HD-TVI TURBO HD 3.0 Camera: Hikvision DS-2CE56F7T-IT3Z (ceiling, 3MP, 2.8-12 mm motozoom, 0.01 lx, IR up to 40m)Ceiling IP Camera: Hikvision DS-2CD1143G0-I (4MP, 2.8mm, 0.028 lx, IK10, IR up to 30m, H.265/H.264)Compact IP Camera: Hikvision DS-2CD2085FWD-I (8MP, 2.8mm, 0.01 lx, IR up to 30m, WDR, H.265/H.264)PoE Switch: ULTIPOWER 2216af (16xRJ45/PoE-802.3af, 2xRJ45-GbE/2xSFP), managedHD-TVI TURBO HD 3.0 DVR: Hikvision DS-7208HUHI-K2 (8ch, 5MP@12fps, H.265, HDMI, VGA)Multi-system Ceiling Camera: Hikvision DS-2CE56H0T-VPITF (5MP, 2.8mm, 0.01 lx, IR up to 20m, HD-TVI, AHD, HD-CVI, CVBS)
The DS-7208HUHI-K2 M75509 DVR normally supports 12 camers (8 analog cameras up to 5 MP and 4 IP cameras up to 8 MP). In the Enhanced IP mode it can support 16 cameras (8 analog cameras up to 5 MP and 8 IP cameras up to 8 MP). After switching off analog cameras, it can operate with 16 IP cameras up to 8 MP.
The Enhanced IP mode eliminates the intelligent image analysis in analog channels and limits the video resolution of the HDMI/VGA outputs to 1080p. The mode can be switched on only with local access to the menu of the DVR.
Image analytics in IP CCTV systems. Video surveillance systems are developing very dynamically. Several years ago, motion detection was practically the only alarm event used for streamlining the management and operation of CCTV systems. Nowadays, IP cameras offer advanced image analytics to facilitate the recording, classification and searching of important events. The examples include license plate detection/recognition, facial detection, detection of crossing a virtual line and/or intrusion into a defined area, detection of emerging and disappearing objects in a given zone. The use of such solutions makes it unnecessary to spend hours searching a lot of recordings. The "intelligent" functions can minimize the volume of the recordings as well as can make the searching process much easier and quicker.
The diagram below presents a scheme of IP CCTV system based on Hikvision IP cameras of Easy IP 3.0 series and Hikvision DS-7608NI-K2 K22074 NVR with H.265 video compression. A number of intelligent functions available in the cameras and supported by the NVR allow for creating a system where the searching for recordings will be very quick.
Compact IP Camera: Hikvision DS-2CD2025FWD-I (2MP, 2.8mm, 0.005 lx, IR up to 30m, WDR, H.265/H.264)4K IP NVR: Hikvision DS-7608NI-K2 (8ch, 80Mbps, 2xSATA, Alarm IN/OUT, VGA, HDMI, H.265/H.264)PoE Switch: ULTIPOWER 0098af (9xRJ45, 8xPoE 802.3af)HDD Western Digital PURPLE WD30PURZ 3TB (3.528
IP CCTV system based on Hikvision devices supporting intelligent image analysis
The cameras deployed around the building cover the whole area. The recording is triggered by alarm events in the form of motion detection, detection of intrusions into defined areas, detection of crossings of virtual lines. The detection areas has been defined in the cameras directed towards the entrance gate and wicket. In addition, the entire area around the house was covered with virtual lines. The detected direction of crossing the lines is from the fence towards the house.
The searching for recordings can be focused on the event that the user is interested in. If there is a suspicion that a person has come through the wicket or gateway, the search option should use the detection of intrusion into the inner area. If someone could jump over the fence crossing a virtual line, it can be quickly found by searching the recordings using this attribute. The last but always important method is to search for recordings using motion detection. This will allow the user to quickly search for any incidents with minimized number of false alarms.
The cameras and NVR support ANR function, which ensures video recording on the memory cards inserted into the cameras in the event of network problems, and synchronization of the recordings with the NVR after restoring the communication. Both the cameras and NVR support H.265 video compression, so that the recordings can be stored 2 times longer than in the case of H.264, with the same disk capacity.
WDM (single-fiber) vs. duplex (two-fiber) links. Installers can choose solutions based on Wave Division Multiplexing (WDM), which require only one fiber for bidirectional data transmission or those with two fibers (duplex). Choosing a solution, they usually take into consideration its cost and the number of fibers available in the cable. However, there is one more technical aspect associated with the use of one or two wavelengths.

A graph showing the dependence of the attenuation on the wavelength in the case of:
microbends (blue), macrobends with 20 mm (red) and 25 mm radius (green)
(The data come from studies of the Cabelcon company)
The graph shows that accidental fiber bending will result in different attenuation for different wavelengths - for example, a 20 mm bend does not cause significantly greater attenuation at the wavelength of 1310 nm, but in the case of the wavelength of 1550 nm, the attenuation of the bend will exceed 2 dB. Compared with normal attenuation of the fiber at the level of about 0.25 dB/km, the loss increase is gigantic.
In the case of systems using more than one wavelength, every installer should be aware of the above phenomenon. That is why it is generally recommended to take measurements at all wavelengths used in the installation.
A wider choice of server cabinets! DIPOL has introduced new models of standing server RACK cabinets. The cabinets of the series have perforated front and rear doors. With this feature, it is possible to cool devices located inside the cabinets with external air conditioners. The spacing between the pairs of mounting rails located on both sides of the cabinets can be adjusted with a step of 1 cm, which definitely facilitates the assembly of servers and other devices. The cabinets have lockable side walls.
KOMAG INSTITUTE OF MINING TECHNOLOGY confirmed the compliance of the Signal RACK cabinets with EN 62368-1:2015-03:
The document issued by KOMAG INSTITUTE OF MINING TECHNOLOGY in Gliwice, Poland, confirming the compliance with general safety requirements contained in Chapter II of the General Product Safety Directive (2001/95/EC) of 3rd December 2001 and in the guidelines of the EN 62368-1:2015-03 international standard. The test procedure included e.g. testing the mechanical strength and protection against access to live parts.
The new items include server cabinets with perforated doors, with 24U and 32U height, and 800 mm and 1000 mm depth:
19" Signal server RACK cabinet
24U 800x800 mm, standing
19" Signal server RACK cabinet
24U 800x1000 mm, standing
19" Signal server RACK cabinet
32U 800x800 mm, standing
New products offered by DIPOL
Surge Protection Box: Signal ZMZ-12 (12 paths, mast-mount, for multiswitch systems)
Surge Protection Box: Signal ZMZ-12 (12 paths, mast-mount, for multiswitch systems) R48614 has been designed for comprehensive protection of SMATV systems based on multiswitches. The device protects all the satellite and terrestrial TV paths (12) against voltage surges induced in signal lines by lightning strokes. Intended for mounting on a mast/pole, with the R90610D pole mount.

23.6" LED Monitor: HIKVISION DS-D5024FC (HDMI, D-Sub, BNC, RCA) M30236 has been specially designed for continuous operation in CCTV systems. Its LED-backlit display with native resolution of 1920x1080 pixels correctly renders colors and has a low response time of 5 ms. The input video signal can be provided via HDMI, VGA, or BNC input. The monitor implements VESA 100x100 mounting interface standard.

Ceiling IP Camera: Hikvision DS-2CD2325FWD-I BLACK (2MP, 2.8mm, 0.005 lx, IR up to 30m, WDR, H.265/H.264)
Ceiling IP Camera Hikvision DS-2CD2325FWD-I BLACK K17303B is dedicated for professional IP CCTV systems. The compact camera has been equipped with high quality 2 MP 1/2.8" CMOS sensor providing perfect video coverage even in low-light conditions. Along with IR illuminator with range up to 30 m, the camera can also operate in complete darkness. The built-in 2.8 mm lens has 108° viewing angle. The IP67-rated housing of the camera protects the electronics against adverse weather conditions. The camera can be powered conventionally with a 12 VDC source or with the use of PoE option (802.3af).
Worth reading
Distribution of HDMI signal to multiple TVs, with control of the source via USB. The Signal-HD H3613 HDMI to IP converter enables the user to connect a remote (up to 100 m) source of HD content to an HD-enabled television/monitor, using one CAT5e/6 cable. The set includes transmitter and receiver units. USB ports in the units allow for remote control of the source of the signal, e.g. a computer/DVR/NVR etc. by using a mouse or other device... >>>more
An application of the H3613 HDMI > IP converter/extender set and additional two H3613R receivers (point-to-multipoint configuration with an Ethernet switch)
TERRA class-A multiswitches with 4-year warranty
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