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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 36/2009 (Nov. 2, 2009)
2009 Nobel Prize in physics for groundbreaking achievements in fiber optics. The Royal Swedish Academy of Sciences awarded half of this year's Nobel Prize in physics to Charles K. Kao "for groundbreaking achievements concerning the transmission of light in fibers for optical communication", and the other half jointly to Willard S. Boyle and George E. Smith for the invention of the CCD sensor (more information on the latter in the previous issue).
The research conducted by the Chinese physicist allowed a rapid development of fiber optic technology. First experiments with rays of light guided by glass fibers were conducted in 1870. Thanks to the phenomenon of total internal reflection the beam was propagated through the fiber, but the transmission was possible only on short distances. This resulted from high attenuation of light waves, reaching up to 100 dB per kilometer (currently, attenuation of modern optical fibers is about 0.2 dB/km).
The situation radically changed in 1966 when Charles Kao published the results of his research and pointed out the cause of so high attenuation. He proved that pollution of the fiberglass with hydroxide ions and ions of elements such as iron, copper and cobalt was the main reason of this phenomenon. The study also proved that another reason of increased attenuation was dissipation of energy occurring in the glass structure due to its inhomogeneity. Thanks to the publication of Ch. Kao, already in 1970 the followers were able to obtain the first pure glass fibers without such contaminants and flaws.
Currently fiber optic networks connect the whole world being the main means of communication and transmission of huge volumes of data between any parts of the worldwide information infrastructure.
Nowadays fiber optic installations are competitive in price compared to traditional wiring, and they have far more transmission capacity. It's the reason why they start to reach end users (FTTH - Fiber To The Home).
Example of FTTH (Fiber To The Home) project
integrating Internet access, telephone service and TV,
based on 10 Gigabit Ethernet
When the infrastructure does not keep up - Shanghai. The growth of the Chinese economy is very impressive. The driving force behind the development are large cities, and Shanghai is among the leaders. This largest Chinese conurbation quickly becomes the richest city of the world. Majestic skyscrapers in the Pudong business district prove the potential of the Chinese building industry. However...
Television panorama of Pudong district
- TV tower at night and array of satellite dishes by a high-rise building
... in the rush it is difficult to pay attention to every detail, so sometimes one can spot such temporary installations:
Improvised arrangement on the main street of Shanghai - Nankin Road.
What an imagination!
MAC layer - a few words on WiFi - part 10. In the 802.11 standard, if the frame exceeds the maximum length, it can be sent in fragments. After sending the first portion of the frame, the station releases the channel and waits for confirmation (ACK) from the destination station. When the confirmation has been received, after SIFS time the station can transmit another fragment.
An example of frame fragmentation
The frame header contains a field informing other stations about how long the transmitter will occupy the channel to transmit the frame. The length of the period takes into account the time needed for transmission of the frame and the time indispensable for confirmation from the receiving station. The channel busy time is called Network Allocation Vector (NAV). After reading the frame header, all stations other than the addressee of the frame are inactive (busy virtual channel).
Using the NAV mechanism
To ensure proper transmission in the case of hidden stations, the 802.11 standard also uses RTS/CTS ((Request To Send / Clear To Send) mechanism. The RTS/CTS frames ensure some redundancy (RTS - 20 bytes, CTS -14 bytes), hence the use of this mechanism is particularly useful when sending long frames. In the case of sending short data frames, the ratio of control frames to the data frames becomes too large, which significantly reduces the efficiency of the network resources. Therefore, the RTS/CTS mechanism is turned on beyond a certain length of the frame.
When the RTS/CTS mechanism is enabled, the station which won the competition for access to the medium - before sending the data frame - must send the RTS frame. Then, the destination station acknowledges this fact by sending CTS frame. This ensures that all stations that are not involved in the transmission will remain inactive for the time specified both in the RTS and CTS frames (transmission hold-on).
Transmission of frame using RTS/CTS mechanism
In the next part we will present PCF mode.
Multiswitches for professional installations. Technical parameters significantly better than those of similar devices on the market, reliability, extensive range of models well-suited for the requirements of investors, 24-month warranty, availability of quick service - are the criteria allowing to include some equipment to the professional group. TERRA multiswitches fulfill these requirements, and, according to opinions of installers and the editorial staff of "SatKurier", are the best products on the market.
TERRA company provides two kinds of these devices: cascadable multiswitches (MS series) and radial multiswitches (MSR and MSV series - the latter can be powered remotely). TERRA multiswitches allow to build SMATV systems up to 1000 outlets. Each of the series is divided into two subgroups: 5-input (for one satellite and terrestrial TV) and 9-input (for two satellites and terrestrial TV).
number of inputs
5 or 95 or 95 or 9
number of outputs44, 8, 12, 16, 24, 324, 8, 12, 16, 24, 32
max number of outlets in one system
active terrestrial TV
SAT gain adjustment
NOYES - one satellite
YES - L and H bands of both satellites
powerfrom amplifier or end multiswitchlocal (built-in power supply)from amplifier or local power supply (18V)
TV/SAT Wall Plate: Signal R-TV-SAT (terminal)SAT/TV Splitter: Terra SS-5049/16 Multiswitch: TERRA MSV-916 (active terrestrial path)9/16 Multiswitch: Terra MSR-916 (active terrestrial path)
The diagram shows an example of installation with MSR and MSV multiswitches. The red line denotes terrestrial path. Selecting "ON" position of the DC switch of SS-504 splitters, it is possible to power the MSV multiswitch from the power supply built in the MSR multiswitch (via "H" lines). If a system uses more MSR multiswitches, they have to be DC-isolated at the splitters.
ULTIMODE optical attenuators. ULTIMODE equipment includes fiber optic devices and accessories indispensable for implementation of optical networks. The range of accessories containing patchcords, pigtails and adapters also includes highest quality optical attenuators:
  • ULTIMODE T-12 L4512 (attenuation of 2 dB);
  • ULTIMODE T-15 L4515 (attenuation of 5 dB).
ULTIMODE optical attenuators (SC female to SC male) can cooperate both with single-mode and multimode optical fibers, in any transmission widow. Using optical devices over short distances, one should make sure that the signal strength at the input of the receiver will not damage the device. The attenuator should be connected directly to the input the receiver.

Optical Attenuator ULTIMODE T-12 (SC, 2 dB)Optical Attenuator ULTIMODE T-12 (SC, 2 dB)
Optical attenuator ULTIMODE T-12 (SC, 2 dB) L4512
Optical attenuator ULTIMODE T-15 (SC, 5 dB) L4515
What does it mean "a good DVR"? The quality (and price) of a CCTV DVR mainly depends on the type of DSP (Digital Signal Processor), operating system and software capabilities. These factors translate into the functional advantages of the device, in particular:
  • maximum resolution of recording,
  • maximum number of fps (single channel, specified resolution),
  • compression method,
  • number of recorded audio channels,
  • number and maximum capacity of supported hard drives,
  • possible modes of work, specifically multitasking (e.g. pentaplex, triplex, etc.),
  • support for network functions, depending on the needs,
  • configuration options.
Of all the above parameters, the especially important one is the maximum number of frames per second recorded at the maximum resolution.
For example, the information about a 16-channel DVR that it records 400 fps, without giving whether this parameter applies to CIF or 4 CIF resolution, is a common marketing gimmick used by the manufacturers of cheap DVRs. Similarly, in the case of 4-channel DVR they often inform about recording 25 frames at a resolution of 4 CIF without stating whether this applies to all channels or each channel. Another misinformation is giving parameters of live monitoring instead of recording.
12 questions for those who plan to build CCTV installation - part 3. After determining locations of camera points, the next important step is establishing managing structure of the system. It includes supervision, operation, recording.
4. What is the required level of automation?
One should expect a maximum level of automation of the system, because man-operated systems are expensive, and - in the long run - less reliable. The system should provide solutions that will help the operator to control its main functions, from PTZ control to image analysis.
Therefore we can see an increasingly important role of the software known as IVS (Intelligent Video Software) that allows for:
  • Advanced Motion Detection - resistance to interferences such as changing light or weather, shadows etc.,
  • Left Object Detection,
  • Motion Tracking - tracking of moving objects,,
  • Facial Detection - recognition of people,
  • Vehicle Identification - identification of license plates, ,
  • Object Persistence - analyzing persons/objects that stay in the field of view for a long time,
  • Fire Detection,
  • People Counting,
  • Traffic Flow,
  • Action Analysis - scuffles etc,,
  • Flow Control - of crowds of people (at stadiums etc),
  • Attention Control - analysis of the time that people spend observing an object (at exhibitions, shop windows etc).
Video surveillance software
Maintenance-free NVR
5. What should be the reaction/s of the system in case of violating some individual areas?
A modern CCTV system allows, through the relay outputs of the DVRs, for direct response to various events (e.g. detection of light, opening/shutting the door etc.), as well as for indirect actions through transferring the control signals to other security systems. The response to breaching a zone may depend on cooperation with other systems:
  • burglary and robbery alarm system,
  • fire fighting system,
  • access control system.
The signals from alarm inputs can, for example, switch on recording of specified camera/s after opening a gate or detecting a fire, as well as they can trigger more complex operations: switching on recording, sending pictures and activating relay outputs.
IP Camera ULTICAM DS-852MF-E (2.0 Mpix)
The rear panel of the ULTICAM K1441 camera with alarm input/output for cooperation with other systems
A megapixel magnifying glass. Megapixel cameras can be used on production lines - for quality control, in operating rooms - for archiving and educational purposes, in education and training - to show small details to a large group of participants.
The following photos were taken during a training course. To show the participants the details of the mobile phone screen, there was used megapixel camera ULTICAM K1441 with Tokina lens M2235. The set allowed to reach high quality 2 Mpx image, and the lens with 4.5-13 mm focal length was suitable for capturing the interesting area from a very small distance.
The camera K1441 focused on the display of a cellular phone and the image displayed by a projector
Device marking conventions of ULTIAIR family. ULTIAIR is a series of professional Access Points, designed for efficient long-term outdoor operation. ULTIAIR devices are characterized by short delays and high throughput. They are recommended for creating efficient wireless IP CCTV and ISP networks. They can be managed via WinBox utility or telnet. They operate in unlicensed 5GHz band - no special permissions are needed. The devices can operate as client or base stations. Below we explain device marking conventions of ULTIAIR family.
Mikrotik license levelAntenna gainAntenna directivityIntended use
3, 417, 19, 23K, S, DC, N , B
 3  3rd level 17  17 dBi K  Directional C  Client
 4  4th level 19  19 dBi S  Sector N  Nstream
 23  23 dBi D  Omnidirectional  B  Base station
The difference consists in the number of supported protocols and modes of work. It is shown in the table above (License levels).Higher gain enables transmission over longer distance
The exact angles are available in specifications of every ULTIAIR device.

C  For P2P connections.
N  Very efficient transmission.
B  For base stations.

  • N2300 - Wireless Access Point ULTIAIR 419KC
  • N2301 - Wireless Access Point ULTIAIR 423KC
  • N2310 - Wireless Access Point ULTIAIR 319KC
  • N2311 - Wireless Access Point ULTIAIR 323KC
  • N2312 - Wireless Access Point ULTIAIR 319KC 166AG
  • N2313 - Wireless Access Point ULTIAIR 323KC 166AG
  • N2320 - Wireless Access Point ULTIAIR 423KN
  • N2330 - Wireless Access Point ULTIAIR 417SB
  • N2335 - Professional HotSpot 2.4GHz ULTIAIR 415SB
Wireless Access Point: ULTIAIR 323KCWireless Access Point: ULTIAIR 423KCWireless Access Point: ULTIAIR 423KCWireless Access Point: ULTIAIR 323KCULTIAIR
Example of wireless link with an intermediate node,
based on ULTIAIR devices
Adjustable LCD/plasma mounts for demanding customers - Monako DP107. The DP107 series of LCD/plasma mounts has been designed for mounting these modern flat displays on vertical walls. The brackets are manufactured in three models for TVs/monitors of different size (diagonal) and weight:
  • 30"-50", up to 60 kg - E9621,
  • 32"-60", up to 80 kg - E9622,
  • 42"-70", up to 100 kg - E9623.
The mounts allow easy adjustment of tilt (without additional tools) in the range of -5 to 15 degrees. It is also possible to rotate the panel +/- 40 degrees and adjust the distance from the wall (in order to use connectors on the rear of the panel or get access to some controls). The entire structure is based on a strong arm that allows to move the panel away from the wall at a distance up to 25.4 cm (10").
Fully adjustable Monako mounts of DP107 series
allow optimally adjust the position of the mounted LCD/plasma panel
"ULTImonitoring." This is the name of the integrated offer of DIPOL, containing CCTV devices, software and transmission means for city video surveillance systems. The concept will be presented at the 10th Alarm Video Surveillance Conference and Exhibition in Kielce, Poland, from November 4-5, 2009. There, we will also show modern professional IP CCTV systems in action and new equipment for optical transmission. We invite Polish speakers to the lecture on ULTImonitoring on Nov. 5 at 11:15, as well as everyone to our stand during the trade fair.
ULTIMONITORING at Alarm Kielce, Nov. 4-5, 2009
Those who cannot visit our stand in Kielce, can easily review the Virtual stand
introducing the ULTImonitoring concept
We have written about:

Moisture-resistant cable - TRISET-11 PE Total Cu. TRISET family has a new member - TRISET-11 PE Total Cu E1029. The inner conductor, foil and braid are made of copper, which allows to use the coaxial cable in wet environments - there is no risk of corrosion due to presence of water, typical for aluminum. The cable is protected by PE (polyethylene) sheath...
- archive DWR of Dec. 3, 2007

ULTISYSTEM for schools. At nights CCTV systems in schools often work without operators - the images from outdoor cameras cannot by analyzed in real time (the indoor cameras/systems usually have automatic alarm functions)...
- archive DWR of Nov. 24, 2008

Modular Headend TERRA MMH-3000. A headend or head station is a set of professional satellite (and often DVB-T) receivers equipped with RF modulators. Each of the modules receives different program. It enables distribution of digital satellite and terrestrial programs, re-modulated in analog format for viewing on existing televisions...
- Library

Index of published issues
ULTIMONITORING at Alarm Kielce, Nov. 4-5, 2009
George Popescu
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