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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 4/2008 (Jan. 28, 2008)
Security has its price - large sports events. Worldwide sports events, drawing the attention of millions, issue a challenge for protection of such mass gatherings. Due to high risk of terrorist attacks the organizers take great responsibility for safety of all the competitors and spectators.
The well-known tragedy at the Olympics in Munich in 1972 is a memento of a worst-case scenario. A group of Palestinian terrorists burst into the Olympic village and took hostages. As the result of unsuccessful action of the police, there were killed 11 competitors from Israel, 5 terrorists, an one German policeman.
The cost of security measures at the Olympic Games in Los Angeles, 1984, was 79 million USD. With 6,829 competitors and 5,720,000 sold tickets it means 11,627 USD to one athlete and 14 USD to one fan.
At the next Olympics the costs of protection of a single competitor / a single spectator were (USD):
  • Seoul 1988 - 13,312 / 34
  • Barcelona 1992 - 7,072 / 22
  • Atlanta 1996 - 10,486 / 13
  • Sydney 2000 - 16,062 / 34
  • Athens 2004 - 142,857 / 283 (source: Wall Street Journal, Aug. 22, 2004)
A turning point in the rate of increase of the costs was the attack on the World Trade Center in 2001 - see the immense growth in 2004 (Athens).
The cost of security measures at Beijing 2008 Olympics is not known yet, but it will probably beat the record. In Beijing alone there will be installed 260,000 CCTV cameras. (source: China Public Security International). Out of concern for security, the organizers cooperate with best safety experts from US and Israel.
The security budget for the Olympic Games in London is planned to reach 400 million USD. The number of cameras in London will have been increased to 500,000 (source: BusinessWeek, Aug. 15, 2005), which is difficult to imagine, also thinking of the network of monitoring centers and the number of the staff.
Monitoring of sports facilities is a must. In the picture - CCTV cameras at San Siro in Milan.
Head stations of Alcad - for SMATV systems and cable operators. DVB-S receivers, also called QPSK/PAL transmodulators, allow to receive digital MPEG-2-compressed programs and convert them to the form used by standard televisions (VSB-AM modulation, versions for PAL B/G (CCIR), PAL I (UK), and PAL D/K systems).
This solution can be effectively used for 200 or more outlets, but it is also very suitable for smaller antenna systems, e.g. in boardinghouses, motels, hotels etc. The number of available satellite channels may be limited to several only, but the main advantage of such a system is independence from individual satellite receivers - the guests' rooms are equipped only with televisions - no troubles with operating satellite equipment nor possible damages.
Single DVB-S receiver (module) allows to convert one digital satellite program into analog PAL channel, selected from among special (cable), VHF, or UHF bands.
The TP-569 R912128 receiver has possibility of installing CAM (Conditional Access Module). It supports any encryption system which does not need pairing smart card with CAM or receiver.
The internal modulator using VSB-AM modulation enables adjacent-channel operation, with maximum output level of 83 dB.
Typical installation using TP modules

Cabling for multiswitch systems. SMATV systems built with multiswitches are multi-cable installations - in the conduit there are several coaxial cables distributing different signals. In large buildings the lengths of the cables can reach tens of meters. It involves a risk of crosstalk between the cables. The interferences increase BER which may lead to loss of frames etc. To avoid crosstalk the installer has to use at least A+ class cable. DIPOL offers TRISET. cables that fulfill this requirement. The risk of using cheaper cables of unknown parameters is too high - they may be the reason of unstable work of receivers and will have to be exchanged for better ones in any case.
TRISET-113 PE gel-filled cable (E1017) used for connecting antennas/LNBs with indoor devices/multiswitches
The TRISET family includes:
  • E1015 TRISET-113 - for connecting multiswitch outputs with subscribers' outlets.
  • Top-quality RF distribution cable. The quality has been confirmed by "Product of the Year" prize at SatKrak 2007 trade fair. Main features: low attenuation, very good screening efficiency, great flexibility allowing easy installation (including connection to outlets).
  • E1017 TRISET-113 PE GEL-FILLED for connecting antennas/LNBs with indoor devices/multiswitches. The sheath of the cable (polyethylene - PE) is resistant to UV radiation. The gel between the sheath and the braid protects the inner part against penetration of humidity/water.
  • E1025 TRISET-11 PE GEL-FILLED - for linking subnetworks, suitable for building very extensive systems. In comparison with TRISET-113 - lower attenuation, but the same excellent screening efficiency (A+). PE sheath and gel-filled - it can be laid directly in the ground, without any additional protection.
  • E1027 TRISET-11 HF i E1019 TRISET-113 HF (Halogen Free) - due to HF (halogen free) technology, the cable is suitable for making installations in schools, hospitals etc. where fire regulations require such cabling.
Connectors for multiswitch systems. The connectors used in multiswitch installations make up a small part of the overall costs, but are very important for signal quality, reliability of the system, and - last but not least - they condition labor consumption during the installation work. Improper or low-quality connectors may reduce signal levels and expose the system to internal (from other polarizations) and external interferences. It happens that most of the time is waisted looking for bad connections. Thus the importance of the proper choice.

An important parameter of every RF connector is VSWR. In satellite band it shouldn't be higher than 1.5 dB. Another crucial parameter, especially significant in multiswitch systems, is screening efficiency. For bran-name connectors the value is higher than 70 dB. For professional purposes there are usually used crimped connectors - quicker to mount, better shielded, more precise and stable.
DIPOL offers professional F connectors of Platinum series suitable for indoor and outdoor applications, with distribution and trunk cables, ensuring screening efficiency over 100 dB. The tool indispensable for crimping the connectors is TR-255 E80077.
For connecting cascadable multiswitches there are used "quick" F-plug/F-plug connectors - E8242.

Professional F-connector: Platinum (on TRISET-113)
F-male to quick F-male adapter
The connector crimped on TRISET-113 E80274 cable
"Quick" F-plug/F-plug connector - E8242
Reception of satellite TV at a campground. Satellite broadcasts enable travelers, e.g. those traveling all around Europe, to receive programs in their mother tongues. It applies both to holiday tourists and truck drivers. To use the opportunity the travelers may employ very useful mobile satellite dish A9535.
The dish can be mounted with the sucker, or on a mast. Mounting and demounting is really an easy task.
During the tests performed in Krakow (Hotbird 13oE, overcast and rain) we got BER of the signal 10-3 (before correction). Such value allowed satisfactory reception of MPEG-2 stream.
Mobile Sat Dish: Camping 35 (offset)
The suitcase makes the set really mobile - A9535
PoE technology in IP CCTV. Growing number of IP devices have possibility of powering over Ethernet (PoE). Transmission of electrical power, along with data, to remote devices over standard UTP cables is the cheapest solution It additionally allows easy implementation of Uninterrupted Power Supply (UPS). For IP CCTV devices with PoE compliant to IEEE 802.3af (48V) there can be used the PSA16U-480 M1890 power supply. It allows to run the system with only one UTP/FTP cable which transmits data and provides supplying voltage.
When an IP device does not have PoE capability, there may be used N9205 adapter. It is important to realize that in this case the supplying voltage has to be compliant with requirements of the powered device (it has to be guaranteed by the supplier used). The adapter and UTP cable cannot transmit more than 400mA - it means a limit for the maximum power consumed by IP devices working at a relatively low voltages (e.g. 12V).
PoE Power Supply PSA16U-480
PoE Adapter (with leads)
PoE power supplier PSA16U-480 M1890
PoE adapter N9205
Network neighborhood of IP CCTV. IP CCTV (Internet Protocol CCTV or CCTV over IP) is implementation of closed-circuit television in IT network infrastructure, with use of typical network protocols. Due to high capacity requirements - transmission of video and sound - the network has to ensure efficient data transfers, especially in the case of high-resolution video transmission. For appropriate streaming of the data it is indispensable to use QoS (Quality of Service) mechanisms - resource reservation control to guarantee required level of performance to the data flow.
But reservation of the resources or even separate network are not the only requirements for efficient IP CCTV system. The performance of the system mainly depends on efficiency of the network components used, cabling, and network configuration. To ensure full compatibility of all the devices, it is recommended to employ equipment from one manufacturer, with specifications compliant with the expected transmission rates.
The most important parameters include maximum number of packets per second - pps, and maximum throughput (in kbps, Mbps, Gbps, or kBps, MBps etc.).
The both parameters should be specified explicitly for every device (as a whole, or of its individual ports). The parameters have to be balanced with the needs of the cameras, web servers, NVRs - to achieve highly efficient IP CCTV system.
ACTi cameras are equipped with two network interfaces - LAN and WAN - with independently set parameters
MPEG-4 DVRs of KPD series - efficient network operation. The main advantage of the DVRs is smooth network operation. Thanks to MPEG-4 compression, video transmission does not require so wide band as in the case of many other DVRs.
There may be up to ten simultaneously logged-in users. The remote access can be used by IE or client program. The manufacturer also provides free multi-client software pack - allowing to manage several recorders from the family.
Apart from features listed above, the recorder possesses one more key function. It is possible to define two different image qualities, this one which is suitable for local recording (usually of higher definition), and that one which is sufficient for distribution via the Internet. The function is very essential when line speed is relatively low - conscious choice of quality allows to transmit the images smoothly, whereas local good-quality recording ensures proper identification and analysis capability of the archival data.
MPEG-4 DVR: KPD-604PL - 4 channels
Remote monitoring of dispersed locations with KPD608 M8504 DVRs and Multiclient software
VIDEO / VGA converter. The 15-AD01 M1688 device converts color composite video (CVBS) or S-VHS signal to VGA standard. It allows to connect CCTV cameras, SAT receivers, DVD players, VCRs, or any other source of standard video signal to a VGA monitor. Due to pass-through concept of VGA signal path, the computer and monitor can be normally operated. No additional software is required. There can be used CRT or LCD monitors. The converter may be operated with the included remote controller.
Selection of the signal is performed by the "Source" switch, which is placed on upper part of the device. The control panel is also equipped with other switches: POWER, MENU and "UP", "DOWN" navigational buttons. Brightness, contrast and saturation settings are available in the menu. All information concerning the type of source or change in parameter settings is displayed on screen (OSD). The frequency of the output signal can be set at 60 Hz or 75 Hz, there are available the next resolutions: 640 x 480, 800 x 600, 1024 x 768.
VIDEO / VGA Converter 15-AD01
The main application of the converter is fast and reliable monitoring of video from a chosen video device while performing computer activities. The converter is an external device working independently and is installed between the computer (graphics card) and the monitor.
Router configuration. A router connects one computer network with another network, e.g. the internal network (LAN) with the external network of ISP (WAN), making a bridge for information flow. Without appropriate configuration of the router it is not possible to access the second network. Typical solution consists in replacing the computer working in the external network by the router (being in fact a specialized computer performing tasks of routing and forwarding), to create the internal network.
In this case, the computer configuration involves:
  • taking down all settings of the NIC (working in the external network),
  • changing the way of address assignment to dynamic (DHCP),
  • connecting the computer (NIC) to the LAN port of the router
After restarting the computer, using an Internet browser, there is possibility of accessing the router by entering its IP address. After logging-in (the passwords can be found in the user's manual of the router) it is needed router configuration:
  • WAN port - there should be entered the previously taken down parameters (or activated the default settings option - DHCP Client),
  • LAN ports - the DHCP server requires:
    • setting the initial address of the address range,
    • setting the end address of the address range,
    • setting the subnetwork mask.
It should be remembered that the address of the internal LAN have to be different than that of the WAN port. For example, with IP address of WAN, the LAN network can be addressed 192.168.(not 1).1. With such configuration of the DHCP server the local computers can obtain their IP addresses automatically. It is very convenient solution.
Planning to use access point, it is needed:
  • to choose suitable channel,
  • to set SSID,
  • to set data encryption and cryptographic keys.
It is indispensable to change the default passwords in the Administrator panel. On the Internet there are active programs which try to log in to routers of the users that have forgotten to do so.
Switch TP-Link TL-SF1008D (8 ports)
Example application of TL-WR542G N2950 router - LAN with access to the Internet
We have written about:

Lenses for megapixel cameras. The market offers a number of cameras with megapixel image sensors. High resolution of the image sensor means also adequate requirements for the lenses. Low quality of the important component of such a camera would spoil the overall quality of the set....
- archive DWR of Aug. 20, 2007

AI lens - how is it built and how does it work? Most of currently manufactured CCTV lenses use DC Iris or Video Iris control. The lenses are comparatively cheap due to clever drive system. In general, the iris my be driven by a small motor (much more expensive solution used in still cameras), or by electromagnetic actuator....
- archive DWR of Sept. 10, 2007

Quality of digital video recorders - speed and resolution of recording. There is a big difference between a 400 fps/CIF DVR and that 400 fps/ D1...
- archive DWR of Oct. 1, 2007

Index of published issues.
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