DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN

OTT TV - time for diversity.

The term OTT TV (Over-The-Top Television) is defined as transmission of video content bypassing the traditional distribution channels (terrestrial and satellite broadcasting, cable TV).
The expression Over-The-Top comes from the trenches of World War I, where, aside from the meaning of a "normal" military order, anyone who had lost their mind from war trauma would disobey orders and climb over the top of the protective trenches, risking their life. Coming out from the "trenches" of traditional TV broadcasting means the transition to the Internet, so the new way of distribution is also known as ITV (Internet TV).
However, OTT TV is different from IPTV due to its openness - the transmission is performed over normal Internet infrastructure, instead of dedicated networks, and versatility - it can be received on all devices which allow the use of the Internet (computers, phones, televisions equipped with Internet interfaces) - as opposed to IPTV, which requires dedicated set-top boxes.

TV on the Internet is still at the stage of development of the business model. OTT includes live video transmissions which are currently tested on a large scale by Google and services such as VoD and "catch up" - downloading any content available on the servers at any time chosen by the customer, but also services added to traditional TV and provided via the Internet, such as access to the content (Accessing), payments, games, etc.
In the field of commercial OTT TV, the most popular projects are: Hulu in the US, Nederland 24 in Holland, ABC iView in Australia, BBC iPlayer, 4od, ITV Player and Demand Five in Great Britain.
OTT openness also means the possibility of transmission performed by non-commercial users and small businesses. Using software such as Media Server, anyone can post transmissions of local events, conferences, etc. The most popular software of this type includes Adobe Media Server, Wowza Media Server, Windows Media Server, Icecast and Shoutcast streaming media servers.
The main challenges for OTT TV are: still low bandwidth of majority of Internet connections, lack of standards, a small number of television sets equipped with Internet connectivity.

Fantasy in antenna systems.

Implementation of a telecommunication installation is rarely a subject to aesthetic judgment. The way of mounting antenna equipment determines reliability and long life of the system. But sometimes in these mundane topics one can find aesthetic fantasies and futuristic looks, like in the image below.

We invite you to take part in the "Engagingly about antennas" contest. The works can be submitted from June 1st, however the pictures can be taken anytime - just look for an interesting topic!

"A tree of happiness"
Grazyna Ziarnowska

What to pay attention to when measuring digital TV signals?

The increasing popularity of DVB-S2 standard and progressive digitalization of terrestrial TV broadcasting encourage installers to explore the field of measuring digitally modulated signals.

For analog signals the most important parameters that should be measured are the levels at the input of the distribution network and the C/N (carrier to noise) ratios.
Due to the nature of digitally modulated signals it is impossible to distinguish a single carrier - the signals are similar to noise and C/N measurements are not relevant. In addition, in the case of a digital signal the most important thing is not the signal level, but its quality which is determined by a number of parameters described below.

The basic parameter providing information about digital signal quality is BER (Bit Error Rate). It indicates the possibility of an error in the bit stream. Digital signals transmitted via RF channels (DVB-S/S2 and DVB-T) are broadcast using double redundancy coding. This increases the bandwidth requirements for signal transmission, but allows the receiver to correct errors arising in the transmission channel by means of appropriate corrective algorithms (Viterbi and Reed-Solomon corrections).
Most meters available on the market have the ability to measure two types of bit error rate - BER (Channel BER - CBER, also marked bBER or PreBER) and aBER (bit error rate after the first step of signal correction - Viterbi - also marked as PosBER). It is very important to distinguish these two parameters. From the perspective of the installer, the measurement of aBER, whose value is approximately one million times smaller than the BER, in most cases is pointless.
It is assumed that a digital signal with BER equal to 1E-4 (1 erroneous bit per 10000 bits) has a good quality - is Quasi Error Free (QEF). For HDTV signals the BER should be not higher than 1E-6.

Professional DVB-S/S2, DVB-T, DVB-C, and analog signals analyzer Rover Scout ST2+ R10830

Most installers, having meters with only basic functions, limit measurements to signal level and bit error rate. Meanwhile, the equally important parameter is Modulation Error Ratio (MER). In fact, it is an equivalent to S/N or C/N for analog signals, with the difference that aside from amplitude noise it also takes into account other noise components, such as phase noise - very important in the case of digitally modulated signals.
The difference (ratio) between the measured and minimum MER shows the margin possessed by an installation, protecting proper reception (margin to the point of cutting out altogether). A deterioration of this parameter practically does not affect the quality of reception, until it reaches this point - the minimum value (the border between proper reception and lack of reception can be as narrow as 1 dB).
Typical and minimum values of MER depend on modulation schemes (QPSK, 8PSK, QAM ,...) and FEC (Forward Error Correction) parameters. For example, in the case of digital terrestrial television (DVB-T with QPSK modulation) and FEC=2/3, the minimum and typical MER values are 14 dB and 17 dB respectively.

It is also important to analyze constellation diagrams. They carry information about the types and levels of noise influencing digital signals.

Monitoring of entries.

At the moment of opening the door a large amount of light comes into the room and the camera has to quickly adapt to the changeable lighting conditions. There is similar situation in the case of glazed door - the cheaper cameras do not provide satisfactory results. To avoid such intense light the installers usually mount the cameras as high as possible or on the left or right side of the room. But such location of the camera does not allow good identification of the people coming in.
Professional solution is provided by application of CCTV camera equipped with PIXIM sensor, SN-586C/B WDR M11208. The sensor has been designed and built in such a way that it automatically adjusts the exposure time for each pixel separately, providing superb results in unprecedentedly wide dynamic range.

CCTV camera with Sharp sensor.

Our editorial staff has conducted a simple comparative test of the u-cam 092 M11283 camera equipped with 1/3'' SHARP CCD sensor, with a similar camera from a well known manufacturer, with the same parameters (420 TVL, 0.5 lx), equipped with SONY sensor. Using identical lens (TOKINA TVR2714DCIR M2315) and saving the images on a DVR with a higher recording resolution than that of the cameras, we have compared the recorded images.
The images in original format differ very slightly in tint, but are practically identical in sharpness and contrast. After a 10-fold digital zoom, the both fragments of the images are blurried, which is normal for cameras of this resolution, but they are still very similar.
Due to small size and attractive price, the u-cam 092 M11283 camera is popularly installed in offices, businesses, small shops and houses.

Color CCTV camera u-cam 092 M11283
with horizontal resolution of 420 TVL and high sensitivity (0.5 lx)

iVMS4500 - mobile phone surveillance application.

The possibility to access a video surveillance system from mobile devices is increasingly becoming a vital requirement of investors.

Hikvision company, in addition to dedicated software for advanced video monitoring systems, provides its customers with iVMS4500 program - a simplified version of iVMS4000.
The application is designed for cell phones and PDAs. There are many versions that support different platforms (Java, iPhone), but the most popular one is for Windows Mobile.
Detailed hardware and system requirements can be found in user manual.

The program allows to add multiple devices - both with fixed IP addresses and those using DDNS. Images from different DVRs can be viewed on one screen.

Maximum image resolution is CIF - compared with screen resolutions of PDAs and cell phones, it is fully satisfactory.
The program uses auxiliary streams sent by ULTIMAX/Hikvision DVRs. It enables the user to set 6 levels of image quality, bit- and frame rates. The application allows for automatic selection of optimal settings - for users who want to quickly setup the connection.
In the preview window the user can start video recording, capture screenshots, control PTZ cameras.

An application of the iVMS4500 program

The user can connect to the DVRs and IP cameras from anywhere, using data transmission via GSM/UMTS services (2G, 3G), or using the local WiFi network. This is an excellent solution for the security staff - the person patrolling some location(s) can simultaneously monitor other ones.

iVMS4500 supports ULTICAM cameras ( K1140, K1440, K1441 ), Ultimax DVRs ( M71040, M72040 ) and Ultimax/Hikvision DVRs. The program version for Windows Mobile is available for download at DIPOL website in Download section.

Remote control of electrical equipment - the integration of Aviosys camera(s) and watchdog.

IP Power Switch &Watchdog Aviosys 9258HP N3410 allows remote control of four AC power outlets (via the Internet network) - switching on/off up to 4 devices powered via the outlets. One of its distinguishing features is the ability to set for each output a specific date and time when the connected device is to be switched on/off or reset (switched off and on). The configuration is done using multi-event scheduler.

Integration of the camera(s) with the watchdog enables:

Control of a level crossing and a gateway

Remote control of various devices can be achieved using wireless transmission means provided by ULTIAIR equipment (it requires mutual visibility of the points), or employing optical transmission equipment of ULTIMODE series. Thanks to the use of ULTIMODE media converters, the remote devices can be controlled over distances of a few kilometers from the management center. The optical equipment applied in the example above meets the high reliability requirements.
In the diagram above, the operator has the ability to rise and lower the barrier and open/close the gate. The Aviosys 9070 IR K1162 cameras allow the operator to monitor current situation in those locations.

View of the preview and management window of AVIOSYS N3410

DIPOL at Securex trade fair in Poznan, Poland, April 26-29, 2010.

Securex trade fair has been opened. Even without being there, you can visit DIPOL's virtual stand . DIPOL presents a comprehensive range of mutually compatible CCTV devices, software and means of transmission based on the concept of ULTIMONITORING.
We also introduce a new generation of infrared illuminators - Redbeam - nominated for the Securex 2010 award.

We have written about:

CCTV transmission via the Internet - part 1/3. IP CCTV devices (IP cameras, video servers) and DVRs with built-in web servers allow to access the surveillance video via the Internet. The problem is still the choice of devices and proper configuration of their network parameters so that the video has satisfactory quality despite bandwidth limitations...

Use of Dual Stream function

Central power distribution in multiswitch systems. Modern multiswitch installations should be powered from one central point. This solution is easier to implement, without the need of supplying 230VAC to every installation box with the multiswitch.
The leading manufacturers of multiswitches implement this kind of power distribution in their products...

4 burglaries in one year - a good reason for monitoring of underground garage. Underground garages are easily accessible for thieves. Standard locks on the gates do not ensure sufficient safety level. Another problem is poor lighting in corridors.
In the garage of one of the housing cooperatives in Krakow there were 4 burglaries in one year. A dozen or so garage boxes were robbed each time. There were acts of vandalism and assault.
In order to increase security in the underground garage, the members of the residential community decided to install a video surveillance system...

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