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

The driving force behind broadband Internet.

In early January, the Broadband Forum reported the results of the third quarter of 2011 in the expansion of broadband services in the world. During this period there was the largest quarterly increase since 2009. Of all the last-mile technologies used, the access through broadband DSL still dominates, but the fastest growth is occurring in FTTx fiber-optic networks.

In the third quarter of 2011, 19 million new FTTx lines were deployed, two times more than in the same period of 2010. As the report underlines, the pace of construction of fiber optic lines is also likely to continue in the fourth quarter of 2011. The market share of fiber-optic technology is now almost 16%, quickly catching up with (coaxial) cable technology, 19.5%, (the remaining market share belongs to DSL).

Zhone's MXK platform - solution selected by 150 operators in 40 countries

The world leader in FTTx solutions is Zhone Technologies Inc. which in late January announced the deployment of over 3000 MXK platforms around the world. This figure is impressive considering the fact that the total capacity of these platforms allows for providing services to nearly 30 million users. Each system, depending on the needs of the operator, can serve from 64 to 9216 users. Not without significance is the range up to 60 km. Over last three years, the number of end users who access the services through the MXK platforms increased by 450%.

In the twentieth century, the construction of roads and highways was the method to stimulate the economy during the crisis, now the building of modern telecommunication systems is considered to be a similar mechanism. In the field of cable systems, fiber optic networks can play the most important role in modern economy.

The concept of xPON networks [telnet-ri.es]

The solutions used in MXK platforms are based on GPON technology (Gigabit Passive Optical Network).
GPON technology uses only passive distribution networks (optical cables and unpowered optical splitters) linking the service provider's central office with the end users, including the "last mile". The active (powered) components of the system are located solely at the central office (Optical Line Termination - OLT) and at the end users' sites (Optical Network Terminations - ONTs). This is the main advantage of GPON technology over existing solutions based on active Ethernet switches.

Depending on the needs of the developers, GPON solutions can be implemented as FTTC (Fiber To The Curb), FTTB (... Building), FTTF (... Floor), and the most expensive but also the most powerful and forward-looking FFTH (... Home) providing the users with virtually unlimited bandwidth.

Appearances can be deceptive.

CCTV transformers (baluns) match the impedance of coaxial video outputs (unbalanced, 75 ohm) to the impedance of the balanced lines (100 ohm, usually pairs of UTP cable), and vice versa, the impedance of the balanced lines to the impedance of coaxial inputs of the signal receivers (DVRs etc). The cheap items of that kind may look similar to professional, more expensive devices, but they are usually made in the simplest way and have low parameters that deteriorate image quality (noise, stripes, running lines, skew).

Passive video baluns of Etrix series have been designed to meet the highest standards - they do not cause distortions and are resistant to environmental conditions.

Items that seem to be identical have a completely different structure

The figures show the comparison of cheap baluns available on the market (Fig. A and B) and an Etrix balun (Fig. C).
Unlike the competitors, the windings of the Etrix balun are mounted on a PCB. The board is directly attached to the connector and the whole unit is protected against mechanical damage by durable polymer case. Additionally, at the UTP (+/-) side there is protection against voltage surges.

Common headend for two hotel buildings.

The owner of one of the hotels near Warsaw had it equipped with MMH-3000 Terra headend. Then, he faced the problem of distributing the signal from the headend to another building. Thanks to the fact that already in the construction phase the buildings were connected by multi fiber optic cable, most of the low voltage systems (television, Internet, video monitoring) in the both buildings could be easily integrated.

Satellite TV signal is fed to the second hotel building via optical fiber

The signal from the headend has been split into two paths, with the use of the R60102 passive splitter: the signal for the building with the headend (42 rooms, 46 outlets in total) and the signal fed to the second building (a total of 28 outlets). The first building is also equipped with broadband building amplifier Terra HA-126 R82303 which adjusts the signal level to the distribution in the network with long cable segments.

The optical transmitter MOS-211A R81720 has been placed in the server room in the first building.
The cabinet visible in the picture also houses PCS-200 R8171 remote control interface.

The optical transmitter Terra MOS-211A R81720 sends the signal from the headend to the second building. In this case, the distance from the optical transmitter to the optical receiver OD-120 R81724 is about 280 m, a very short length in terms of optical transmission. The signal level at the output of the OD-120 receiver (113 dBuV) is sufficient for feeding all the outlets through a passive distribution network.

Optical video converters solve the problem of installing CCTV system in a lighthouse.

The investor in a seaside town decided to open the local lighthouse to visitors. To protect the tower from devastation, ensure safety for tourists, and oversee the operation of the key equipment of the lighthouse, he decided to install video monitoring system. At the design stage there was a problem with the choice of an appropriate transmission line, which had to be run in parallel with the power cables. So, the only medium which could be used in such environment was optical fiber.

The video monitoring system in the lighthouse

Initially, the monitoring system has been equipped with 3 analog cameras, the final solution will consist of 8 cameras. The transmission is based on the pair of video converters ULTIMODE L2802, which can transmit up to 8 video channels and 1 one-way RS-485 data channel for control of a PTZ camera. The video is recorded by Signal M78308 DVR (also capable of supporting 8 channels) and monitored on a professional CCTV monitor SAMSUNG SMT-1923 M3019 (19").

Who needs a camera with 24 VAC power supply?

The main advantage of powering cameras with 24 VAC voltage is the lower required cross section of the wires, due to reduced current. Using the same cable as for a 12 VDC camera/option, it means that the 24 VAC version can be used over twice the distance. Additionally, the 24 VAC mode shows a great tolerance to voltage fluctuations - the cameras usually ensure stable operation beginning with 15 VAC.

The Sunell SN-BXC0583C M11195 camera can be powered from a 12 VDC or 24 VAC source.
Its built-in voltage converter provides galvanic isolation of the power and signal paths.

In addition, Sunell cameras with 12 VDC / 24 VAC circuitry provide galvanic isolation of the power and signal paths. It eliminates interference caused by ground loops and deteriorating image quality. In cheap cameras, the grounds of the power circuit and signal output are directly connected. This is often the cause of poor quality of the video. In such cases, the use of external isolators usually does not solve the problem.

How to properly connect the NT-4040(R) NVR to the LAN?

The NUUO Titan K4204 NVR introduces the new "File Ring" recording engine supporting megapixel resolutions. It is capable of downloading and archiving the total data stream with a bandwidth of 250 Mbps. This bandwidth is sufficient for receiving and recording video data from 64 5-megapixel H.264 cameras.

The NVR must also simultaneously provide online video streams from the cameras and the played back streams from the NVR to the client workstations. The use of a single Gigabit Ethernet port could be not sufficient.

To separate the data streams from the cameras and those transmitted to client workstations, the NVR has been equipped with two Gigabit Ethernet ports. This prevents overloading the network and increases the reliability of the system (in the case of a failure of one of the two network adapters the second one can continue the basic functions).

The recommended network architecture of IP CCTV systems
based on NUUO Titan NT-4040(R) K4204 NVRs with two Gigabit ports

The recommended network architecture separates the video streams from IP cameras from the streams sent to client stations. The K4204 NVR, the N29940, N29952, N29950 switches and client stations use the 1000 Mbps connection, whereas the individual cameras are connected to 100 Mbps ports.

The architecture fully exploits the capabilities of the NVR server - connection with up to 128 cameras (e.g. each of four clients can access online images from 32 cameras) and playing back archives from up to 64 channels (e.g. each of eight clients simultaneously plays back 8 recordings).

The first 3G mobile router from TP-LINK.

The TP-LINK TL-MR3020 N2959 device is a 3G travel router with a compact size of 74x67x22 mm, which provides access to the Internet for Wi-Fi devices in any location covered by a 3G network.


The device has the following operation modes:

An example application of the TP-LINK TL-MR3020 N2959 device -
four devices can be simultaneously connected to the Internet via a 3G network

Thanks to the built-in AP, the device allows the user to create a wireless local network. A computer is added just by pressing the push button (WPS). The access to a 3G network is obtained by connecting an external 3G modem.

Worth reading:

MATV systems in areas with difficult reception conditions. It happens that the parameters of DVB-T signal intercepted by the antenna are not sufficient for its further distribution in the MATV system. The problem usually occurs in areas with poor terrestrial signal levels. The signal received by the antenna cannot be directly amplified or converted to a different frequency due to high BER and low MER levels...

The idea of using the ttx311 R81714 regenerator

How to split optical signal - FTTH. FTTH networks (Fiber To The Home) are based on PON architecture (Passive Optical Network). This means that between the service provider's central office (the node called OLT - Optical Line Terminal) and each subscriber (with ONT - Optical Network Terminal) there are no active devices and the signal is passively split between the subscribers (in the case of GPON to up to 128 users), using optical splitters...

Passive optical network using optical splitter ULTIMODE SP-16B L3616

Intelligent IR illuminators in Sunell cameras. Compact cameras are often equipped with high-power IR illuminators to ensure maximum range. This solution, however, has a major drawback: if the observed object approaches the camera, it is overexposed and becomes unrecognizable.
The cameras Sunell SN-IRC4920AJ M11245 and SN-IRC5920AHLDN M11280 have function of intelligent IR lighting (Smart IR). The signal processor continuously analyzes the image and in the case of areas with excessive brightness it lowers the output power of the IR illuminator. In this way the images of the people or vehicles approaching the camera are recognizable. Such functionality is particularly useful in the case of monitoring entrances and all the places where the observed objects approach the camera...

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