DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 34/2016 (Oct. 24, 2016)
Polymer laser from Poland. The world's first electrically powered polymer laser has been developed by researchers at the Adam Mickiewicz University (UAM) in Poznan. They demonstrated that synthetic polymers, the basic building blocks of plastics, could be pumped by electric current to emit monochrome light. It was previously known that some polymers were able to emit laser beams, but the emissions had to be excited with intense light from other sources, often from other lasers. The scientists at the University of Poznan are the first in the world who have shown that a polymer powered directly by electrical current can emit laser beam. The UAM staff has been able to obtain the emission using a conductive polymer (poly-aniline). This is the first conductive polymer obtained in Poland as early as in the seventies of the last century by the chief of the team, Prof. Jerzy Langer, on the basis of the analysis of the structure of a popular dye, called black aniline, used e.g. to protect the surface of laboratory tables. The solution with the polymer laser developed by the Polish scientists is currently a subject of further research and analysis.
According to the developers, in the future such lasers could revolutionize medicine and electronics. The work on the creation of the polymer laser was carried out in Poznan for over 10 years. The world's leading laboratories were also trying for years to create a polymer laser powered by electricity, but without a success. Electrically powered polymeric lasers will be cheaper than conventional lasers. The production process should be much faster and they can be more extensively used in many industries, medicine etc. The scientists from Poznan say that it is possible to obtain monochrome or polychromatic beams - from ultraviolet to infrared. These are extremely valuable properties in the case of lasers.
- Exir IR illuminators have increased lighting efficiency and IR light beams matched to the rectangular field of view of the cameras.
- "Black Glass" with increased light transmittance in the infrared range, ca. 90% (versus typical 80%). As a result, with the same parameters of IR illuminators the range of operation is broader. An additional advantage of this solution is the lack of visibility of the IR LEDs in daytime.
- Varifocal lenses are of motozoom type, allowing for easy adjustment of the viewing angle.
Hikvision TurboHD 3.0 DS-2CE56D7T-IT3Z M7518 camera has invisible Exir IR LEDs and motozoom lens
Measurements of optical links with the transmission method. Basic measurements of attenuation of optical links, necessary for qualification tests, are based on the transmission method. With the use of an optical power meter and optical laser source with predetermined output level and high stability, the installer can measure the total attenuation of the whole link, including connectors. However, when the measured attenuation is higher than expected, the fault (a bad splice or connector, excessive bending, factory defect of the cable etc.) cannot be easily found. For such a thorough test it would be necessary to use an optical time-domain reflectometer.
Using the transmission method, the installer should select the appropriate wavelength - depending on the transmission window in which the link is to operate, or according to accepted standards. Without specified requirements, the most comprehensive testing should cover all the wavelengths specific for the type of the fiber used, i.e. 850 nm and 1300 nm for multimode fibers, and 1310 nm, 1550 nm, and 1625 nm in the case of single-mode fibers.
Testing optical links with connections in distribution frames/boxes, it is necessary to calibrate the measuring system. For this purpose the installer can use two patch cords (with connectors compliant with the source of light / power meter and the frame or box, respectively), and suitable optical adapter.
Calibration of the measuring system
Measurement of the attenuation of an optical link
In the case above, the attenuation of the optical link is 6.5 dB (the measured power level of -16,5 dBm compared to -10 dBm obtained during calibration). Most optical power meters can remember the calibration value as a reference point. Then, such meter will show only the attenuation of the tested segment (in the example it would be -6.5 dBm).
Intercom function in Hikvision NVRs. Hikvision DS-7604NI-E1/A K22043 is a modern IP network video recorder capable of monitoring, recording and playing back images from four megapixel IP cameras at frame rates up to 25 fps from each camera. The NVR has audio input and output, which enables two-way audio communication between operators or between an operator and anyone by a camera with built-in or external microphone (connected to the audio input in the camera).
The video from the IP cameras plus bidirectional audio information is transmitted according to IP protocol as a data stream, thus it can be easily distributed e.g. between buildings (in LAN network) or over longer distances (on the Internet). The intercom functionality can be used by operators for convenient voice communication, for rapid response in the case of incidents etc. To allow the communication, the AUDIO OUT of the NVR has to be connected to an active loudspeaker (with built-in amplifier) and the AUDIO IN to a suitable external microphone. If the monitor connected to the NVR has built-in speakers, there is no need for an external speaker (the monitor can be connected via HDMI cable, or VGA cable and audio cable). Of course, the second surveillance post must also be equipped with a microphone and a speaker. A diagram illustrating voice communication between two posts is presented below.
The use of intercom function in an IP CCTV system
Satellite TV in hotels and other facilities. Headends distributing satellite channels after conversion to DVB-T COFDM digital form are popular solutions used in many hotels. Satellite channels can be a complement to terrestrial TV broadcasts or be the main or only source of programming in the system. Digital Terra headends can be used in a wide range of hotels and other facilities with different number of rooms, including the largest ones. Thanks to the conversion of DVB-S/S2 signals into DVB-T COFDM standard, the satellite programming can be received by regular televisions, similarly to normal DVB-T broadcasts. Thanks to the same DVB-T COFDM standard, both the terrestrial DVB-T broadcasts and the converted satellite channels can be easily distributed to TV outlets located in all rooms, via typical TV installations based on coaxial cabling.
Four-channel amplifier Terra at440
(UHF, DVB-T, AGC) R82511
DVB-S/S2 (8PSK, QPSK) - DVB-T (COFDM)
transmodulator TERRA TDX410C R81617
- Terra at440 R82511 is a four-channel highly selective tunable RF amplifier capable of filtering, amplifying and equalizing four digital multiplexes (DVB-T) broadcast in the UHF band. Each of the four independent sections can amplify different DVB-T multiplex. The paths are equipped with automatic gain control (AGC) and ultra selective SAW (Surface Acoustic Wave) filters. The automatic gain control ensures automatic equalization of signal levels to 82 dBμV (for input levels within 50-75 dBμV range).
- TDX410C R81617 transmodulator is used for reception of DVB-S/S2 (8PSK/QPSK) signals, selection of desired channels from a transponder, and retransmission of them in COFDM format in chosen channel in VHF/UHF frequency range. In multiplexing mode, one panel receives a whole multiplex (up to 10 or so channels) and converts it to DVB-T multiplex with up to 5 services (max. 31 PIDs), ant total bit rate up to 31,66 Mbps. In the need for a higher bit rate, one can employ another TDX-410C R81617 module.
- Universal DIN rail mounting bracket R82538 matching 19-inch RACK cabinets.
- SIGNAL 19" Rack Cabinet (6U 600mm, hanging) R912017.
Easy way to power network devices. PoE (Power over Ethernet) is the name of a number of methods that allow for powering network devices through UTP/FTP cables. This way it is possible to power devices such as cameras, phones, switches, access points, etc. In 2003, the IEEE established 802.3af PoE standard, upgraded to 802.3at in 2009. 802.3at distinguishes between the first type (prior 802.3af) and the second type with maximum transmitted power of 30 W, nearly two times higher. The second type is suitable to power cameras with high-power IR illuminators, IP telephones, small network printers etc.
The ULTIPOWER 0054af N29980 PoE switch is a desktop device enabling smooth data transmission in 10/100 Mbps Ethernet networks. Its five RJ45 ports support auto-negotiation function, four of them provide power over Ethernet (PoE function). The switch automatically detects PD devices compliant with IEEE 802.3af standard and provides them with power supply. This feature allows the user to expand the network coverage in areas where there is no access to AC power lines/outlets and to employ access points, IP cameras, IP phones, etc.
ULTIPOWER 0054af N29980 - example application diagram
DVB-S/S-2 Receiver Ferguson Ariva 203 A99373 combines the features of a DVB-S/S-2 satellite receiver and media player. The receiver ensures the highest image quality both in the case of high-resolution (HD) and standard (SD) broadcasts. Ariva 203 has two high-speed USB 2.0 ports for plugging both external storage media and wireless WiFi adapter (with RT5370 processor, to be bought separately). Just a few examples of the functions of this versatile device are recording/timeshift, playing music (mp3, ogg, flac), playing movies (mkv, avi, xvid), viewing photos (jpeg, bmp).
HDMI to IP Converter Signal HD (with USB extender) H3613 enables the user to connect remote (up to 100 m) source of HD content to HD-enabled television/monitor, using one CAT5e/6 cable. The set includes transmitter and receiver units. USB ports in the units also allow for remote control of e.g. a DVR/NVR, with a mouse etc.
HDMI - COFDM (DVB-T) Modulator: WS-7990 (4 channels) R86704 is a multipurpose device that converts four HDMI or baseband A/V signals into four DVB-T multiplexes (channels). The signals can have resolutions from SD to Full HD, and can be provided to 4x HDMI or 4x A/V (RCA - SD only) inputs. Additional RF (ANT IN) input can be used for combining the output RF signal with other TV signals.
October 13, 2016 - can a CCTV course be interesting? The best answer is the high attendance on the training courses organized by DIPOL. The interesting formula combines a theoretical part about the properties of HD-TVI 3.0 and IP systems as well as the practical part, during which installers can on a rotation basis perform various tasks at five different stands to check the acquired knowledge and gain practical experience.
Hikvision HD-TVI and IP CCTV systems - theory and practice
Training courses at DIPOL, Krakow, October 2016
Multiswitch SMATV system with fiber-optic links. Fiber-optic SMATV systems provide much more flexibility compared to those based only on copper coaxial cables. In addition to the greater freedom in implementing long transmission lines, the installation of the systems is also easier thanks to replacing the multiple thick cables by a single, thin fiber-optic cable. It means that the deployments of the shared antenna systems can be easier for implementation, especially in existing buildings equipped with narrow shafts or even without such conduits... >>>more
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No. 33/2016 (Oct. 17, 2016)
Start of 5G! HDMI with USB via twisted-pair cable! The winners of the 15th DIPOL's Summer Holiday Contest 2016....
Start of 5G! HDMI with USB via twisted-pair cable! The winners of the 15th DIPOL's Summer Holiday Contest 2016....
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TO KNOW MORE
ULTIPOWER Ethernet industrial switches enable data transmission at rates of 10/100 Mbps or 1000 Mbps. Their RJ45 ports support auto-negotiation and Power over Ethernet... more »
Systems based on optical fibers are becoming increasingly popular. General availability of comparatively cheap devices converting electrical signals to optical form and... more »