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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 43/2007 (Dec 10, 2007)
Is this a global TV standard? - DVB-SH. DVB-SH seems to be a milestone in development of mobile television.
In the first months of 2008, consortium of companies in the USA will be conducting a pilot program of transmitting broadcasts in DVB-SH (DVB Satellite Services to Handhelds) technology. The consortium of Hughes, DiBicom and Alcatel-Lucent will launch MIM (Mobile Interactive Media) program - the system of transmitting television broadcasts, as well as digital data and communication streams - with the use of geostationary satellites equipped with high-power transmitters (from ICO) and terrestrial UMTS infrastructure.
This sophisticated concept is based on two pillars: the terminals will receive broadcast data both from satellite and terrestrial transmitters, and exchange unicast data (through point-to-point connections) only via UMTS infrastructure (e.g. paid programs - VOD, as well as return channel).
The consortium proposes transferring DVB-H broadcasts from currently used UHF band to S band (2.2 GHz), the same that of DVB-SH. It would give possibility of creating universal mobile platform, easy to run and cheap - due to covering less populated areas by satellite signal. In urban areas, especially inside buildings, the signal would be available via UMTS, or alternatively, DVB-H transmitters.
The suppliers of the equipment for DVB-SH will be Samsung and Sagem. The picture shows UMPC (Ultra Mobile Personal Computer) from Samsung allowing reception of mobile television in Korean DMB standard. The device is equipped with web-cam, still camera, audio and video player, Finger Print biometric sensor, GPS. Connectivity: WLAN 802.11b/g, Bluetooth, HSDPA/Wibro, LAN. Similar devices are to be manufactured for DVB-SH.
Boiled or fried - where are the eggs? There are places where nature makes an effort to meet people's needs. The picture below presents initial thermal processing of eggs - maybe effective to prevent H5N1.

Where are the eggs? - here.
Was the bird encouraged to lay eggs by the ingenious construction of the antenna below the nest?
Economical home antenna system. The installation shown below allows reception of satellite and terrestrial broadcasts. In one, say master outlet one can receive any terrestrial or satellite program, in the rest of the outlets there are available terrestrial programs and the satellite broadcast currently tuned in the sat receiver.
The terrestrial TV signals are amplified by the AWS-1031 B11585 amplifier equipped with separate FM, VHF three UHF inputs. Such a number of inputs allows to connect directly (without a diplexer) up to three UHF antennas (when receiving programs from different directions), or, like in the diagram, two UHF antennas and modulated signal from the sat receiver .
The SilverLine amplifiers belong to the high-quality group. Their very good transmission parameters include strong resistance to external interferences thanks to solid metal housing.
FM Antenna: Dipol 1RUZ PM B (omnidirectional H+V)VHF TV Antenna: DIPOL 7/6-12 (7-element)UHF TV Antenna: DIPOL 19/21-60 (19-element)UHF TV Antenna: DIPOL 19/21-60 (19-element)Indoor Antenna Amplifier: AWS-1031 (FM/BIII/3*UHF/30dB)3-Way TV/FM Splitter R-3 SignalTV/SAT Wall Plate: Signal R-TV-SAT (terminal)TV/Sat Combiner (Diplexer) DC-009 TerraTV/SAT Wall Plate: Signal R-TV-SAT (terminal)
In one outlet there is possibility of receiving any terrestrial or satellite program, in the rest of the outlets there are available terrestrial programs and the satellite broadcast currently tuned in the sat receiver.
TV-Sat Surge Protector. December is traditionally the month when many people buy televisions and satellite receivers. The devices have to be connected to antenna installations thus they are exposed to overvoltages induced in long cables. It doesn't have to be direct lightning stroke - the charges induced even by distant storms can damage sensitive electronic circuitry.
TV-Sat Surge Protector: SIGNAL (F-plug/F-socket)
At the end of May and the beginning of June we ran out of the R48602 surge protectors. Majority of the orders came after spring damages. They could have been avoided had the equipment been protected in advance. It is worth to spend a small amount of money and protect expensive devices to sleep soundly. The installation is very simple and can be done by every owner of TV set and/or sat receiver.
Radiolektronik - the best SAT TV products. In the December issue of the Polish monthly magazine dedicated to consumer electronics we can find a list of products (as well as their descriptions) that won "The Best Product in the Polish Market" titles at SatKrak 2007 exhibition (satellite receivers, converters, dishes).
Simple, cheap and independent 1.3 Mpix video conference system. Growing number of companies use Internet that also provides possibility of transmitting voice and image, with the help of a communicator, e.g. Skype. Unfortunately, such solution has its disadvantages - dependence from the communicator (there may be sometimes problems with reliability), and limited resolution (640 x 480).
Independent conference link can be implemented with the use of two computers (on both sides of the link) with Windows 2000/XP/Vista OS, connected to the Internet, and two P405M K1135 cameras. The cameras have 1.3 Mpix sensors and very sensitive microphones. The video is transmitted as MPEG-4 stream, with resolution of 1280 x 1024 at 10 fps. The sound is very well heard, even if the speaking person is far from the camera. The computers connect directly with the cameras via Internet Explorer 6 or later. Of course, it is possible to conduct a multipoint conference installing suitable number of cameras and opening next windows in the browser. To get connection to camera with local IP address, it is needed to redirect ports in the server or router.
Compact IP Camera: Pixord P405M (1.3 Mpix)
1.3 Mpix IP camera Pixord P405M K1135
Influence of the band on image quality. The theory says that the broader transmission band the better quality of the transmitted image. But how does it work in practice?
Human eye is capable of distinguishing details within certain limits. Small degradation in quality does not influence the comfort of watching such image. But choosing higher compression level, one has to realize that any digital zoom will be pointless - the graininess of the resultant image will be unacceptable.
Below there are shown two images from the same ACTi device. These are screenshots from MPEG-4 ASP streams, which differ only in the band used for transmission. The difference in image quality is visible, but no so substantial, whereas the bands differ markedly (two times).
How much we can narrow the band it depends on the compression method. The most advanced compression methods allow to limit transmission band more radically than simpler ones. Thanks to MPEG-4 ASP compression ACTi devices do not require large network capacity to get satisfactory results. However, it should be emphasized that every kind of compression has its limit. Below the limit, the quality drops dramatically.
Comparison of two MPEG-4 ASP streams: on the left - 1.5 Mbps, on the right - 3 Mbps
Cameras for round-the-clock monitoring. In professional CCTV systems there are used only color Day/Night cameras. Color cameras ensure better identification capabilities of the system. The capabilities are fully utilized during the day (or when the area is appropriately lighted). In low light the cameras switch into B/W mode. But in many models the threshold is too high - the images are black and white whereas they could still provide full-color information. Some other models behave in the opposite way - they switch into B/W mode too late, providing for some time very snowy "color" images, not suitable for identification purposes. The best solution to such problems is the use of SN-468C/W M11206 cameras, where the installer can individually set the threshold. Other important feature of the camera is application of 1/3" SONY EX-View CCD, capable of operation in practically every environment, and providing high-resolution images (540 TVL). The camera has mechanically switching IR filter.
Day/Night Color Camera: SN-468C/W<br />(mechanically switching IR filter, w/o lens)
View of the rear part of the M11206 camera. The settings and adjustments are carried out by using OSD menu, with the five buttons in the upper left corner.
MIG-29 - 3,5" service LCD monitor - useful device for CCTV installer. Service monitor MIG-29 M3104 is a very handy device for anyone installing and configuring CCTV systems. Thanks to small dimensions and mobility it can be easily and quickly connected to a CCTV camera or DVR (that ultimately is to be managed via network), and used for configuring operational parameters.
The set includes BNC/BNC lead, power lead, and special case to be worn on the arm. The monitor can be operated directly from 12 VDC (typical for many CCTV installations), or from set of eight alkaline AA batteries (not included) to be put into the arm case. The latter solution allows for independent powering of the monitor and the configured camera.
Service monitor MIG-29 M3104 allows quick configuration of lenses, cameras, network DVRs. The arm case is a perfect solution for field work.
CCTV power/video cables for indoor and outdoor applications. Coaxial cables with additional wires for powering are specially dedicated for CCTV installations. It is easier to install one cable only, as well as this concept allows to power a number of CCTV devices from one central point (usually the monitoring center) where can be situated main UPS.
For outdoor applications there is used the PE M6501cable, for indoor installations - cables with PVC sheaths - M5995, M6500, M6504.
CCTV Installation Cable (outdoor):XYAP PE 75-0.59/3.7+2x0.50 (power) [100m]
Outdoor CCTV cable - XYAP PE 75-0.59/3.7+2x0.50 M6501 (usually outdoor cables are black)
License for surveillance technician / worker. In many countries, e.g. in Poland, the job of building video surveillance systems requires state or local permits, in the form of license and/or concession. In Poland one has to obtain:

License - permission for particularly assigned tasks/projects connected with protection of people and objects, necessary for every person and firm offering services in this field. License of the 1st level authorizes the person/firm to build installations, license of the 2nd level enables them to design such systems. Application form for both license types can be issued at the same time. No exams are required - only proof of the knowledge in the field of electronics (e.g. diplomas, degree certificates), as well as in some mechanical disciplines. The police will also formulate their opinion regarding the candidate.

Concession - permission for economic activities in the range of technical surveillance services. It is only required for companies that offer services in the scope of securing events or objects which are under obligatory security rules

More about important features of video surveillance systems in The main features required for CCTV systems
What for we use port forwarding. The function is used in many cases:
  • connection with a computer in LAN (e.g. remote desktop),
  • external access to local ftp server (DMZ zone),
  • remote access to surveillance system (real-time monitoring from any place in the world),
  • other services requiring connection directly via specified port, e.g. P2P.
With default NAT (Network Address Translation) settings there is no possibility of running a server available in the Internet, or direct connections. To achieve connectivity there is needed redirection of packets from the Internet to specified port in the computer or other network device. The usually forwarded packets are TCP and UDP.
Below we illustrate the procedure of port forwarding in the device TP-Link TD-8840 N2905.
The table shows example forwarding of network ports of three devices - IP CCTV cameras of Pixord and ACTI.
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