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

Indians have the key to all televisions in the world.

Saankhya Labs unveiled at CES in Las Vegas a revolutionary integrated circuit - SL1001.

The Indian company showed the world's first universal signal demodulator compatible with nearly all current standards.

It supports both terrestrial television broadcasts (ATSC, DVB-T, ISDB-T, DTMB), cable standards (DVB-C, U.S. Cable, Japan Cable), satellite TV (DVB-S), analog TV systems, (PAL, NTSC), and radio broadcasts (FM, DAB, DAB+). This is possible thanks to modern architecture, SDRs (Software Definable Radio), awarded at CES. The IC can also be programmed to transmit video signals in residential and commercial television networks.

SL 1001 is the first and so far the only widely available product of this category with such a wide functionality. By using appropriate algorithms and filters it assures high quality of reception. Due to low power consumption and compact size, the IC is ideal for use in mobile devices, which makes it even more innovative.

The SL 1001 chip from Saankhya Labs enables manufacturers of electronic equipment to create cheap, versatile receivers that will meet the expectations of customers around the world. With the above-mentioned features, the device can significantly contribute to the spread of digital TV - especially in Europe, where currently there is the mess associated with the introduction of various DVB-T specifications in different countries of our continent.

The most common digital TV standard is DVB-T. It is used throughout Europe, in some Asian and African countries, and in Australia. It is based on MPEG audio/video compression, COFDM encoding and multiple QAM modulation.
The US equivalent of DVB-T is ATSC. The difference is the application of 16VSB modulation and slightly different audio codecs.
The Japanese, in turn, have applied ISDB standard, which is also used in South America.
The Chinese DMTB-T/H, used in China, Hong Kong and Macao, is the most advanced standard, creating a common platform for fixed and mobile devices.
As for the satellite transmission of digital signals, the DVB-S standard has its successor (DVB-S2), and the Japanese use a different system, ISDB-S. There is a similar situation is in the the case of cable TV systems, with DVB-C2 and ISDB-C, correspondingly.

Power supply in CCTV systems.

In practice, 12 VDC security cameras tolerate voltage drop up to 1 V. A typical CCTV camera consumes 150 to 250 mA. Taking the upper value, according to the Ohm's Law the maximum distance of supplying power for such a camera is about 50 m for CAMSET M5995 or CAMSET PE M5997 (2x0.5mm²) cable, and about 100 m for CAMSET 100 M6100 or CAMSET 100 PE M6103 (2x1mm²) cable.

In the case of using outdoor housing with a 12 V heater (e.g. M5406), the lengths decrease to around 20 m / 40 m respectively. So, installations with longer cable runs will require to use additional means for power supply distribution. A good solution is application of ZK-40/16 40V/2A M1830 power supply and SK-40 M1831 stabilizer, which can power CCTV cameras via a 2x0.5 mm² cable over distances up to 980 m (without heaters) and 300 m (with heaters).

A significant part of extensive CCTV systems uses twisted pair cables. Using passive baluns Etrix 1VAP M16659, one can send power over distances up to 70 m (cameras without thermostats), or 30 m (cameras with thermostats). The total current carried by a Cat 5e cable cannot exceed 1 A.

More on power supply in CCTV systems can be found in this article: Internet CCTV GUIDE - power supplies and accessories.

What to do after turning off analog broadcasting from Astra 19.2E?

On April 30, 2012, the last analog TV transponder on Astra satellites will be turned off. The owners of hotels and boardinghouses or pensions in Europe, who use analog headends, will face the problem of ensuring continuity of television services. In particular, tourists in many hotels throughout Europe may be very disappointed by not having access to popular German channels such as Das Erste, ZDF, Dritten Programme, RTL, Sat.1, ProSieben.
Below we present a solution that allows guests to watch these and other channels in the highest, digital quality. The solution based on Terra MMH-3000+ headend is suitable both for hotels equipped with older CRT televisions and those using modern TV sets with built-in DVB-T tuners.

The MMH-3000+ headend enables the distribution of satellite TV, also HD channels, analog TV and DVB-T broadcasts, as well as "private" A/V signals e.g. from security cameras and media players. The headend can remodulate (transmodulate) any of these signals to analog PAL channels or digital DVB-T / DVB-C channels. The big advantage of the headend is the ability to easily reprogram the channel plan or even the distribution standard(s).

Below we show an example implementation of TERRA MMH-3000+ headend for the distribution of selected SAT TV channels in digital DVB-T standard in a hotel. In this configuration, the headend can distribute 32 satellite channels. The output signals have the form of eight DVB-T multiplexes (5 from TDX-311 R81711 modules and 3 from TRX-360 R81709 modulators). It is also easy to add terrestrial DVB-T multiplexes available in the area. The digital standard of output signals ensures uniform reception quality in the whole facility.

Additionally, by using the MD-330 R81713 encoder, the hotel owner has the opportunity to inject signals from three A/V sources of their choice (PC, DVD, media players, analog cameras etc). These signals are carried in the RF distribution network as a part of digital DVB-T multiplex.

An example implementation of TERRA MMH-3000+ headend for the distribution of selected SAT TV channels in digital DVB-T standard in a hotel. In this configuration, the headend can distribute 32 various satellite channels, including three HD services.

The components of the system:

All interested in this subject can find more information in the MMH-3000+ mini-headend system with maxi potential article, or contact us directly to get help in developing a specific solution.

IP CCTV systems based on fiber optic transmission.

IP data transmission over a UTP cable is limited to 100 meters. In order to ensure transmission over longer distances, it is necessary to use optical media converters and send the signals via optical fibers.
IP video surveillance systems with fiber optic backbones are popular and proven solutions for large facilities and areas, such shopping malls, large parking lots, production halls, public areas in cities etc.

A megapixel IP camera provides stream of 4-8 Mbps, so it is sufficient to employ a 10/100 Mbps media converter.

List of 10/100 Mbps ULTIMODE optical media converters:

In the case of transmission of data streams from multiple megapixel cameras from one direction, the cameras should be connected via a switch with SFP module and a gigabit media converter.

List of 10/100/1000 Mbps ULTIMODE optical media converters:

Video transmission over longer distances through coaxial cable.

The range of video transmission over standard coaxial cable (the inner conductor diameter of 0.59 mm) is limited to about 300 meters. In systems requiring longer links, it is necessary to change the transmission medium or use special video amplifiers.

Video signal amplifier VCA-1/2000 M1842 can extend the transmission range up to 2 km

The control knob allows both for gain adjustment and correction of the frequency response of the coaxial transmission line. Together with the increase of gain, the correction becomes deeper. With the range switch the user sets the required transmission distance (400-1200 m or 1200-2000 m).

How to archive data from 64 megapixel cameras?

NVR NUUO Titan K4204 equipped with "File Ring" engine is capable of transfers up to 250 Mbps, thus serving up to 64 5-megapixel H.264 cameras! It can even save images captured by 10-megapixel cameras! Each of its four Hot-Swap drive bays can hold 3 TB SATA II HDD, which allows for about two weeks of continuous recording of video streams from 64 Full HD cameras.

If the material has to be archived for longer than 2 weeks, then the K4204 NVR can be connected to 15 TB disk array via eSATA interface, which increases the data retention period to about a month. An alternative to eSATA is iSCSI (Internet Small Computer System Interface) allowing data archiving on network disks.

NVR NUUO Titan NT-4040(R) K4204 capable of recording video stream from up to 64 H-264 5-megapixel cameras

iSCSI Gigabit Ethernet offers recording speed about 125 MB/s, which is a result similar to the SATA bus bandwidth (150 MB/s). iSCSI-based solutions are the future of IP CCTV systems, because with adequate infrastructure they allow for free deployment of disk arrays, even in locations that are many kilometers away from the monitored area (in "data centers").

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 an 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). Without a special license, in many countries 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:

It is now clear that the borderline value of EIRP may be reached by adequate selection of the transmitter's output power, the kind and length of the cable, and the gain of the antenna used. It is worth stressing that it is much more advantageous to use a lower power transmitter and an antenna with higher gain than the other way round.
Why?
From the link balance we know that the desired radiated power level can be achieved in any way, however, the base station is not only the transmitter, but also the receiver. Then, when it receives a signal from the client station, no matter the output power is in the transmitter mode, the only important parameters in receiver mode are the sensitivity of the receiver and the gain of the antenna. So the gain of the antenna is important both during transmitting and during receiving the signals.
The gain levels of client stations should also be selected carefully. It is no use to have high gain antennas close to the base station, because in transmitting mode they may jam other, even distant networks. Besides that, the receiver "sees" those networks so 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 gain, optimal for the distance, see only the base station and don't cause such problems.

Worth reading:

Antenna system combining satellite and DVB-T signals, with distribution to 4 outlets. The proposed system uses two antennas for UHF band. This configuration is suitable for anyone who wants to receive signals from two transmitters, when the local one broadcasts only one multiplex or there is a possibility to watch foreign channels in border areas. Otherwise, one of the antennas and the antenna multiplexer will not be needed...

Diagram of the antenna system

Network infrastructure for small businesses. During the renovation of the building, the company owner decided to modernize the network infrastructure in the office, so as to ensure a reliable and stable Internet access for 14 employees.
The network modernization objectives were:

ULTIMODE Home System is the ideal solution for small businesses, enabling employees to get access to broadband Internet services, including video conferencing. The connection from the service provider is converted into optical form (POF), and distributed to the hosts, using optical switches ULTIMODE POF-8S L6108...

The POF network in the office

ULTIAIR - IP video surveillance of roads using wireless transmission. Professional access points ULTIAIR are used for the construction of backbone and access networks. An important advantage of the devices is flexibility. Their Linux software allows for creating both very powerful data transmission systems, as well as simple point-to-point links. ULTIAIR devices are ideal for creating high-performance backbone networks for city monitoring systems...

The architecture of IP CCTV system for road monitoring.
The components: Sunell cameras, NUUO NVR, wireless transmission network with ULTIAIR devices.

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