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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 19/2009 (May 11, 2009)
Digital terrestrial television in Europe - DVB-T2. Most European countries are working on implementation of digital terrestrial television broadcasting. The time is short, since the year 2013 is the date of the final termination of analog terrestrial television broadcasting in Europe.
The current transitional period is characterized by an abundance of transmissions, with simultaneously broadcast TV signals in analog and digital form.
Also in the field of digital broadcasting, there is considerable confusion. Currently, there are available the following methods of digital signal broadcasting:
  • DVB-T MPEG-2 - the most popular standard in Europe;
  • DVB-T MPEG-4 (H.264) - used in test broadcasts;
  • DVB-T2 MPEG-2;
  • DVB-T2 MPEG-4 (H.264) - the target digital TV standard for Europe.
Europe is currently dominated by DVB-T/MPEG-2. Some countries chose DVB-T MPEG-4 (H.264) - France, Lithuania, Hungary, Poland.
However, the ultimate standard in Europe is to be the DVB-T2 MPEG-4 (H.264). The first commercial broadcasts in the new standard should be launched in the UK at the end of the year - three HD programs. But the first territory that goes entirely to the new standard will be Granada (November 2009).
The final draft of DVB-T2 was approved last year and the adoption of the final standard is announced for July this year.
Do terrestrial high-power transmitters make sense in the era of satellite broadcasting
- it is a fundamental controversy associated with terrestrial digital broadcasting.
The picture shows the highest TV tower in the world - CN Tower in Toronto.
Electromagnetic radiation and living organisms. Living organisms have always been exposed to natural electromagnetic radiation. Up to the twentieth century, it was the electromagnetic radiation of the Sun and Earth's natural magnetic field. The development of technology, especially telecommunications, have caused major changes, increasing the electromagnetic "garbage" in comparison with the natural background.
So far, multiple research efforts have not clearly confirmed the effect of weak fields on the health of living organisms. However, the impact of mobile phones in the incidence of brain cancers is the current standby topic of choice.
The impact of electromagnetic fields has been taken into account in connection with so-called CCD phenomenon (Colony Collapse Disorder), responsible for the disappearance of about 50% of the population of bees in many countries in recent years. Fortunately for the development of telecommunications, the impact of chemical substances is much more likely in this case.
One thing is certain: the research will continue, especially in the fields of lowering resistance of living organisms and possible influence on DNA code.
Nature adapts well to modern technology - bird nests on antenna structures:
cellular base station in Birmingham; Albania; Spain
Easy installation of large SMATV systems - radial multiswitches with 32 outputs. On the satellite TV market there is a strong demand for multi-output radial multiswitches, but due to technological reasons only a few producers can meet stringent quality requirements. The market leader in this field is TERRA, which has launched in the market the MSR-932 (32 outlets) and MSR-924 (24 outlets) multiswitches.
Attenuation of antenna cable depends on its length, but it is higher for higher frequencies. To compensate the attenuation, the MSR-9XX multiswitches have different signal levels at individual outputs and pre-correction, i.e. the signals of higher frequencies have higher levels. It provides means for compensation of the signal levels in outlets at different distances from the multiswich.
Distinguishing features of the MSR-series multiswitches:
  • small size allowing to put the devices into typical installation boxes
  • built-in cable loss correction
  • groups of outputs with different output levels
  • isolation between outputs better than 25dB
  • powering of optional terrestrial TV preamplifier
  • built-in power supply
  • LNB powered through H lines
9/32 Multiswitch: TERRA MSR-932 (active terrestrial path)
TERRA MSR-932 - 9/32 multiswitch with active terrestrial path - R70832
Analog video transmission in unlicensed 2.4 GHz and 5,8 GHz bands. In many cases, an economic solution for CCTV installations is the use of analog cameras and wireless transmission of the analog video signals.
For installation and use of such equipment for transmitting video in the 2.4 GHz and 5.8 GHz bands no permissions or licenses are required, on the condition that the equipment used meets specified requirements.
A new product in the market is the M1557 wireless transmission system (transmitter and receiver) for wireless transmission of analog audio/video signals in 5.8 GHz band (5725 - 5875 MHz). Both the transmitter and receiver are equipped with channel selectors allowing to choose free operating channel (from among 7 available channels). Due to small size the transmitters can be mounted directly in housings of outdoor or indoor CCTV cameras.
There are also available devices operating in 2.4 GHz (the complete set consists of the M1525 transmitter and M1528 receiver). However, due to congestion in the 2.4 GHz band being the basic frequency range of popular WiFi devices, we advise to skip the possible interference problems by using the 5.8 GHz equipment.

Wireless transmission systems are recommended mainly in situations where there are difficulties with the implementation of wired installations, or the costs of such installations make them uneconomical, e.g. in the case of transmitting video signals over roads, rivers, private areas. Another areas of using wireless transmitting equipment include monitoring of elevators and tunnels. The system shown in the picture, with mobile DVR Sunell MDR4104, can also be used for monitoring outdoor events.
WLAN Panel Antenna: ATK-8/5.5GHz (22 dB; 0.7m cable + SMA/RP)Wireless Transmission System RTR05-s/7<br />(A/V transmission @ 5.8GHz)Outdoor Camera Housing: Marathon MH-806/12Day/Night Lens: COMPUTAR TG4Z2813FCS-IR (2.8-12 mm, DC, F1.3) CCTV 19Mobile DVR MDR4104 (4 channels)WLAN Panel Antenna: ATK-8/5.5GHz (22 dB; 0.7m cable + SMA/RP)Wireless Transmission System RTR05-s/7<br />(A/V transmission @ 5.8GHz)Day/Night Color Camera: SN-468C/W<br />(mechanically switching IR filter, w/o lens)
Wireless transmission of video from a remote CCTV camera in 5.8 GHz band
Notification by email with an attachment on movement detected by an IP camera. Most IP cameras (ACTi, PiXORD) have option of email notification.
This option allows to send emails with specified multimedia information (e.g. .jpeg , .avi), depending on the specific model of the camera. The function is triggered by video motion detection and focused on automatic detection of an intruder and notification of the surveillance staff, owner etc. about the details.
To enable this function, the user has to setup motion detection area (some cameras allow to create several such areas) and sensitivity level/s, then enter the SMTP server information (from which the email will be sent) and the destination address.
After proper configuration, the camera will send email when it detects motion in the areas of detection. The attachment will contain e.g. JPEG image (PiXORD), AVI file (PiXORD), or MP4 file (ACTi) with the reason of the alarm.
The functions can be expanded by additional possibilities offered by the email account, such as SMS notification about a new message, allowing to immediately notify the person concerned about the emergence of an intruder.
Email setting window
The notifications and attachments (pictures or video from the CCTV system)
can be received on palmtops or mobile phones
Megapixel monitoring of dispersed locations. Megapixel video surveillance systems are more and more popular. This is due to the fact that even resolution of 1.3 Mpx provides three times more details than standard CCTV cameras.
However, the use of megapixel cameras sets higher requirements for transmission channels, as well as greater demand for the capacity of recording devices.
While solving the recording demands requires only hard drives of larger capacity, the problems of video data transmission can be a real challenge for IP networks. It is especially critical in WAN networks with limited bandwidth. This case concerns large corporate networks, such as chains of shops, cafes, or gas/petrol stations.
The solution to the problem is use of network video recorders - NUUO K4104, K4108 - which record the megapixel images locally and provide both online remote access to the live video and to the archives. For this purpose it is enough to install in the monitoring center the client software supplied with the NUUO NVRs.
More on this subject in the article NUUO Network Video Recorders - Safe and efficient surveillance video recording
1.3 Mpix Pan-Tilt IP Camera: ACTi ACM-8211Megapixel IP Camera: IQinvision IQ042 (2.0 Mpix)Outdoor Megapixel IP Camera: ACTi ACM-1231Megapixel IP Camera: ACTi ACM-42011.3 Mpix Dome Camera: ACTi ACM-74111.3 Mpix IP Dome Camera: ACTi ACM-3401Outdoor Megapixel IP Camera: ACTi ACM-1231Megapixel IP Camera: ACTi ACM-42011.3 Mpix IP Dome Camera: ACTi ACM-3401Network Video Recorder: NUUO NV-2040Network Video Recorder: NUUO NV-4080Network Video Recorder: NUUO NV-4080
Local recording of megapixel images on NUUO K4104 or K4108 NVRs
Setting up a home LAN network. Router connects two or more computer networks, e.g. external network with Internet access (WAN) with local network (LAN), making a bridge for information exchange.
In most cases, router acts as a specialized computer (replacing a standard computer) working in external network, with software and hardware tailored to the tasks of routing and forwarding. It allows to create internal LAN.
An ideal device for this purpose is wireles xDSL router of TP-LINK - TL-WR340GD N2951 - integrating broadband router, 4-port FastEthernet switch, firewall, and access point.
It has been designed to provide internet connectivity to small and medium businesses, as well as to private users in apartments and one-family homes. TP-LINK TL-WR340GD enables the user to build wireless network quickly and easily and to share Internet connection among a number of computers - ensuring additional protection due to the firewall.

Main features of the TP-LINK TL-WR340GD N2951 wireless router:
  • MAC address cloning
  • firewall
  • Internet access filtering
  • static / dynamic routing
  • AP in 802.11g/b standards (up to 54 Mbps)
  • router
  • built-in 4-port switch
Switch TP-Link TL-SF1008D (8 ports)
Example application of the TL-WR340GD N2951 wireless router in internal LAN with Internet access
Monitoring of construction site. Construction sites are often under video surveillance due to a number of reasons, such as: protection of property, documentation of construction progress, work inspection. Because of temporary character of that places, the installations should be "mobile" at any phase of the undertaking, as well as easily portable to another construction site.
It is provided by the use of IP cameras and wireless transmission, so the cameras can be easily repositioned.

The devices recommended for video surveillance of construction sites:
  • Outdoor Megapixel IP Camera ACTi ACM-1231(1.3 Mpx) - K1511,
  • Wireless Access Point ULTIAIR 419KC - N2300,
  • Wireless Access Point ULTIAIR 319KC - N2310,
  • Network Video Recorder NUUO K4104, K4108 or a suitable PC (video recording),
  • PC with Internet connection for live monitoring and viewing archives.
Outdoor Megapixel IP Camera: ACTi ACM-1231Wireless Access Point: ULTIAIR 319KCWireless Access Point: ULTIAIR 419KC
IP video surveillance of a construction site
Monitoring system based on the devices can be mounted within several hours.
The solution is similar to Mobile video surveillance system for temporary events

We have written about:

Office, business or SOHO WLAN. Internet access is nowadays indispensable functionality of every office block, hotel, warehouse, or small firm. When the building is not equipped with wired LAN infrastructure, the quick, cheap and effective way of solving the problem is wireless network.
TP-LINK in one of the leading manufacturers of network devices for home and business applications...
- archive DWR of March 16, 2009

1-cable, 5-cable, or 9-cable systems in multi-story buildings. The basis for appropriate antenna system is high quality coaxial cabling.
The cabling should be a part of the building design. The cables have to be installed in walls before plastering...
- archive DWR of March 16, 2009

The significance of connectors in CCTV systems. Every connector, even the best one, causes degradation of the signal. The basic rule is minimizing the number of connections in the transmission channel. Usually manufacturers of connectors give two important parameters describing loss of signal...
- archive DWR of Oct. 6, 2008

Index of published issues

Megapixel video surveillance in practice
George Popescu
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