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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 24/2009 (June 15, 2009)
Monitoring of high-risk areas - military bases, airports, nuclear power plants. The threat of terrorism requires effective monitoring of large areas. The technique using normal surveillance cameras is inadequate when the area is shrouded in fog or raindrops, or even at night - due to significantly decreased capability of distinguishing small details. Thus, effective monitoring systems consist of radars, thermal and video cameras.
Radar Vision system developed by CBC Europe Ltd. integrates advanced radar technology and C-AllView Dual thermal and optical cameras, which allows a full-range monitoring effective 24 hours a day and in all weathers, within an eight hundred meter radius.
Samsung Techwin has developed SGR-1 Security Guard Robot. This device consists of scanning and tracking modules. The first one consists of a high-resolution camera and thermovision camera, which in the case of finding an intruder sends information to the second module, still monitoring the entire area. The tracking module is equipped with high-resolution camera, infrared illuminator and laser target positioner. In addition, it is possible to mount weapons, which enables the operator not only to observe the situation but also to "respond" to the trespasser or enemy.
Developed initially for use in the Korean Demilitarized Zone (DMZ), the SGR-1 robot can also be used in areas where unexpected intrusions often call for an immediate action.
You are welcome to watch the promotional video of SGR-1.

Integration of CCTV, radar and thermovision technology
allows effective monitoring of large areas
Think first, do later - a tale about woodpecker. A fairytale is a succinct story that illustrates a moral lesson - let's watch a multimedia version...
Think first, do later
- a multimedia tale
Photo contest "Engagingly about Antennas" - let's look at the sky during the holiday. Subject of the photo contest is a challenge that, at first, seems to be difficult to be up to. What can be interesting in antennas? But we hope the competitors will take up the task that, apart from having aesthetic qualities, requires dash of imagination, grain of wit, and sometimes a certain measure of risk. We hope that the simple definition of the topic - how to make antennas interesting for everyone - will encourage the competitors to use their hidden reserves of untapped talents.
There will be 3 prizes:The works will be adjudicated by photographer and designer from Krakow, Mr. Pawel Zechenter.
This special prize will be awarded by our technical department (the main criterion is ability of conveying technical ideas in an interesting way).

Engagingly about Antennas - VIII DIPOL Holiday Photo Contest 2009
Engagingly about Antennas - VIII DIPOL Holiday Photo Contest 2009
Engagingly about Antennas - VIII DIPOL Holiday Photo Contest 2009
Antenna in the wilderness
Beata Szulinska
By the St Anthony
Henryk Grymuza
The rock
Milan Simek
Multiswitch installation and cable TV - part 2. In the previous issue we have described how to adapt modern multiswitch systems able to distribute satellite and terrestrial signals for connection of cable TV. The subscriber can get via one cable both satellite and cable TV signals.
However, in the case of designing new installation it is recommended to supply two independent cables to each antenna outlet. This solution provides more flexibility, the SAT and CATV signals don't need to be combined in the multiswitches, they are available in the R694140 outlet in separate connectors.

The most flexible multiswitch installations in multi-story buildings are based on 9-cable system. On each floor there is a splitter providing signals to the multiswitches. It allows to shape the network according to actual requirements - there can be deployed practically unlimited number of outlets.
As an example: - According to the developer's requirements, each apartment has been equipped with one satellite cable. But after a year, many or the residents have bought twin PVR receivers and want to get next signal. The solution is simple - on the floors where we need more cables we change the multiswitches for more capacious ones - the rest of the installation does not require any change and the whole system functions normally.

Professional multiswitch systems
SAT/TV TAP: Terra SS-510SAT/TV TAP: Terra SS-510SAT/TV TAP: Terra SS-510SAT/TV TAP: Terra SS-5108-way Tap: Signal O-8 (5-1000 MHz)Subscriber Terminal Outlet:Signal RTV-SAT-R (return path)9/16 Multiswitch: Terra MSR-916 (active terrestrial path)9/12 Multiswitch: Terra MSR-912 (active terrestrial path)
Cable TV in a 9-cable multiswitch system
Outlets for multiswitch systems. Multiswitch systems require only terminal outlets. The main parameters that decide about quality of the outlets are:
  • attenuation
  • return loss
Another important issue is the way of connecting the cable to the socket. It is better when the core and the braid of the cable are screwed independently.
Subscriber Terminal Outlet:Signal RTV-SAT-R (return path)
Subscriber Terminal Outlet: Signal RTV-SAT-R (return path)- R694140.
The core wires are fastened with individual screws, the braids are clamped down with another screw.
It is good to build a network for distribution of television signals and digital data using combined outlets, because more and more devices for receiving television signals also connect with the local network and the Internet. For this type of applications we recommend to use the third of the multimedia outlets:




Basic parameters

 Subscriber Terminal Outlet: Signal R-TV-SAT


Networks with SAT signal and terrestrial signals.

Attenuation ca. 3dB

Outputs: 1xTV, 1xFM, 1xSAT

Subscriber Terminal Outlet: Signal RTV-SAT-R (return path)


Networks with 2 SAT signals, terrestrial signals, and/or return channel.

Attenuation ca. 3dB

Outputs: 1xTV, 1xFM, 2xSAT

Subscriber Terminal Flush Outlet: Signal TV-FM-SAT / RJ-45 / RJ-11


Networks with SAT signal and terrestrial signals, LAN and/or phone lines.

Attenuation ca. 3dB

Outputs: 1xTV, 1xFM, 1xSAT, 1xLAN, 1xphone

ULTIMAX - DVRs for demanding customers - looking through the archives. ULTIMAX DVRs can be fully managed via computer network, ensuring reliable operation. The compression method (H.264) and refined software allow to perform effectively remote video surveillance.
Configuration, management, and playback of the video (also the archived images) is the role of Remote Client Software. The manufacturer has also enabled the users to control the system via Internet Explorer (majority of the functions).

Additionally, in the Download section there is available set of filters that, after installation, enable video playback with Windows Media Player.
There is also available another "player" for playing back the archives, equipped with a number of useful functions, e.g. conversion of video files into AVI format, browsing the video at various speeds, including frame-by-frame analysis, saving pictures in bmp or jpg format.
The archives can be transferred via the network or backed up to any compatible data storage device (flash memory, hard drive, DVD recorder etc.) connected to the USB port or SATA interface.
A palmtop with the image transmitted from ULTIMAX DVR
Megapixel video surveillance system at a gas/petrol station. Shell Kalundborg in Denmark recently contracted modern monitoring system based on ACTi IP cameras.
The solution has been chosen as superior to analog system with 550 TVL cameras. The fact that images from megapixel cameras can be further zoomed, gives the IP system an advantage of reducing the number of cameras.
The station is monitored with five outdoor cameras ACM-1231 K1511 and two indoor cameras ACM-4201 K1514. In this way, the images from each monitored point are recorded with a resolution of 1.3 Mpx - the pumps, cash desk and the store. High resolution of the images allows to read license numbers of the cars, values and number of the banknotes at the cash register, as well as make it easy to identify people in the store.
Outdoor Megapixel IP Camera: ACTi ACM-1231Megapixel IP Camera: ACTi ACM-4201
ACTi megapixel video surveillance system at Shell gas station
Mutual interference between wireless networks. Growing number of the users of unlicensed bands means a greater likelihood of interferences caused by the operation of multiple devices on the same channel. In the case of wireless transmission, one may distinguish two kinds of its range.
Usable range - is the maximum range of the link (guarantying stable connection), whereas interference range says about the maximum distance over which the device can interfere with other devices.

If some base stations interfere with or prevent the operation of our network, we can take the following steps to reduce this phenomenon:
  • change of the channel;
  • change of the polarization into orthogonal one;
  • change of the band (if possible);
  • application of directional antennas.
Mutual interference between base stations.
The station B interferes with the stations A and C, the stations E and D interfere with each other.
Choice of equipment in order to meet EIRP compliance. Are we allowed to use antenna with extremely high gain, not breaking the law? It should be stressed that there are no rules on limiting the gain. So, why one obeys regulations having antenna with 15 dBi gain, while another one breaks them using a 10 dBi antenna?
The answer to the questions follows directly from regulations concerning maximum level of Effective Isotropic Radiated Power (EIRP). In many countries, without special license, the maximum EIRP = 100 mW, i.e. 20 dBm in 2.4 GHz band and 1 W (30 dBm) in 5.47 - 5.725 GHz band. The same level of EIRP may be accomplished by many means:
  • EIRP[dB] = transmitter output power [dBm] - (loss of connectors [dB] + loss of cable [dB]) + ant. gain [dBi] <= 20 dBm (for 2.4 GHz)
  • EIRP[dB] = transmitter output power [dBm] - (loss of connectors [dB] + loss of cable [dB]) + ant. gain [dBi] <= 30 dBm (for 5 GHz)
It is now clear that the borderline value of EIRP may be reached by adequate selection of transmitter's output power, kind and length of the cable, and gain of the antenna used.
It's worth stressing that it is much more advantageous to use lower power transmitter and an antenna with higher gain than the other way round. Why? From the link balance we see that the desired radiated power level can be achieved in any way, however, the base station isn't only transmitter, but also receiver. Then, when it receives a signal from the client, no matter the power being transmitted in transmitter mode, the only important parameters in receiver mode are sensitivity of the receiver and gain of the antenna. So the gain of the antenna is important both during transmitting and during receiving the signals.
The gains of client stations should also be selected carefully. The client who uses a high gain antenna close to the base station, although receives strong signal, may also interfere other, even distant networks when in transmitting mode. Besides that, the receiver "sees" those networks and what it implies, they cause additional noise (the higher noise the larger number of errors and lower transmission speed), or even shares the transmission medium with them - which also effects in lower speed. On the other hand, client stations with lower, optimal for that distance gain, only see the base station and don't cause such problems.
Efficient data transmission with ULTIAIR devices. The most relevant parameters for IP data transmission are maximum data rate and delay of the link. Best results are possible when the devices have high computing power and sensitive radio modules.
ULTIAIR devices have been equipped with motherboards of RouterBoard which ensure adequate computing power needed for efficient transmission.
The application of SparkLan 123AG wireless card and RouterBoard motherboard allows to create long-distance links with throughput up to 24 Mb/s in each direction.
Data transmission rates over 23 Mb/s can be achieved by using Nstreme Dual link. This link employs two wireless transmission channels.
For this purpose we recommend to use ULTIAIR 423KN N2320. It is equipped with two wireless modules that allow to create links with throughput over 40 Mb/s in each direction.
Wireless Access Point: ULTIAIR 423KNWireless Access Point: ULTIAIR 423KN
Nstreme Dual link composed of ULTIAIR devices
Lenny Kravitz in Krakow. The performance of the star playing music that combines elements of rock, pop, and funky will be held on the stage placed on a river boat at Vistula bend during Wianki event on June 20, 2009. The concert of this artist and many other attractions you can see online through our camera directed onto Vistula embankment.
We have written about:

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...
- archive DWR of Jan. 28, 2008

Active video transmitters. Doing a CCTV installation it is often convenient to use thin cables. Sometimes there are needed long cables, over 150 meters...
- archive DWR of Jan. 21, 2008

Overexposed images from CCTV cameras. Image overexposure is a frequent problem occurring in practical implementations of CCTV systems.
Only high-quality cameras with WDR (Wide Dynamic Range) sensors are performing well in the conditions where strong light is directed straight at the camera lens. Below there is the list of cameras equipped with this kind of image sensor...
- archive DWR of May 18, 2009

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