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

HDMI 1.4 - new interface generation for multimedia transmission.

HDMI interface enables transmission of uncompressed high definition video and digital audio via a single, integrated cable. It allows to connect DVD or Blu-ray players, game consoles, set-top boxes, computers to the suitable monitor/television. In modern devices it replaces the older standards: analog (e.g. Composite Video, Component Video, S-Video, SCART, VGA) and digital (DVI).
HDMI story began in 1998, with foundation of Digital Display Working Group (DDWG), which was to develop an interface for digital data transmission. In 1999, the group created DVI (Digital Visual Interface) - a solution based on Silicon Image's technology. HDMI is also based on solutions developed by that company, which formed in 2000 - together with Hitachi, Matsushita Electric, Philips, Sony, Thomson and Toshiba - HDMI Working Group.
Currently, multimedia devices are equipped with the HDMI 1.3a, 1.3b, or 1.3c interfaces, allowing for progressive transmission of video data with image resolution of 2560 x 1600, at speeds up to 10 Gb/s.
The new, HDMI 1.4 version will enable data transfers suitable for resolution up to 4096 x 2160, at 24 Hz.

Additional features of the HDMI 1.4 will include:

Ethernet channel allows for quick, two-way communication between the Internet and HDMI devices. The connected devices can send and receive data at speeds up to 100 Mb/s. With this solution, there is no need for separate Ethernet cable to each HDMI device, it is enough to connect only one device, usually the monitor/television.

HDMI 1.4 adds return audio channel, so that it limits the number of cables connected to TVs. When the TV has a built-in DVB-S receiver, DVD etc., the digital audio signal will be sent to an external audio receiver/amplifier via the HDMI cable.

The new standard will support several 3D formats, including a common HDMI platform. This will enable the viewing of 3D stereoscopic images from game consoles and other sources of 3D applications.

HDMI will support color scheme specifically designed for digital cameras, allowing more accurate color rendition when viewing digital photos. HDMI 1.4 will support sYCC601, Adobe (R) RGB and Adobe (R) YCC601.

The new HDMI specification shrinks the connector size to about 50% of currently used, so it can be easily employed for video transmission from cellular phones or other mobile devices.
Adoption of the new standard is expected in 2010.

Where is this unusual TV exhibit - a titanium ball?

Television station buildings are a part of marketing image of the broadcaster. The intention of the investors is to arouse public controversy and curiosity, because it invariably attracts publicity.
The richer investor and better market prospects, the more impressive building - the leader in this field seems to be the Chinese CCTV (China Central Television).
The owner of the building below is a market leader in one of the richest countries in Asia, having enough potential for creating an interesting element in the architecture of the building - a titanium sphere with a diameter of 32 m, which contains a restaurant and observation platform. An additional attraction is the location of the building - it has been built on an artificial island.
Where is this building and who does it belong to? - As usual, the answer can be found at the end of the issue.

SMATV and cable TV systems with range up to 30 km - fiber optic networks.

Distribution of television signals in systems based on coaxial cables is limited to a circle with the radius of approximately 500 m, due to the relatively high attenuation of the cables.
For larger systems and/or dispersed locations, the investors should adopt solutions based on fiber optic cables. A reliable platform is the complete solution developed by TERRA company.
The signal from MMH-3000 headend (placed in the R81700 base unit) is delivered via coaxial cable to the input of optical transmitter MOS-121B R81720B. It is converted to optical form and transmitted via a single-mode fiber operating in the 1310 nm window. The optical signal can be divided by an optical splitter into several branches.
The device that receives the optical signal at the end of the link and converts it back to electrical form is the optical node R81726. The RF output signal can be split into many subnetworks. According to the manufacturer, one subnetwork can distribute the signal to up to 1000 subscribers.
Expansion of distribution networks based on fiber optics provides modern and cost-effective (the cost of optical cables is nowadays similar to that of high quality coaxial cables) framework for electronic media transmission. In relation to coax networks, optical systems require less maintenance, are completely resistant to interference and allow for connection to modern urban telecommunications infrastructure.

Distribution of the signal from the headend with the use of optical devices

Modulators - the selection criteria.

How to choose an appropriate modulator for our needs, in the most cost-effective way?
Let's compare three models from different price levels, with diverse parameters and functions.

Signal Digital Classic R95176 is a reasonably priced modulator for household use. In practice, it is suitable for distribution of AV signals from satellite receiver, DVD player etc. via home antenna installation to one or two remote televisions, up to distances of about 50 m.
A very practical feature is the use of SCART connector for baseband input signals, and pass-through output SCART connector (loop), which allows for normal connection of the local TV set to the source of the AV signals with the use of typical SCART-SCART cable.

Higher RF output levels of Terra modulators, among them MT47 R871747, allow to use them in larger installations. They can be recommended for injecting video from CCTV cameras or some satellite channels received by typical satellite receivers into in-building antenna installations. Output level adjustment allows for compensation for the attenuation in passive components used in the network.

Modulators of the MT-30 series (e.g. R871731) are from the top shelf. To shift the baseband video to an RF channel, the series employs VSB (Vestigial Side Band) modulation, so that the distribution of the channel does not require gaps in the channel scheme (unlike in the case of cheaper, DSB modulators). It is especially important in systems with multiple channels and many cameras, allowing to double the number of active channels in comparison with DSB modulators.

RF modulators

Transmission range calculation for ULTIMODE devices.

The most important task in the design of fiber optic line is to determine the maximum range of the optical transmission path, being in fact the balance of optical power in the line.
Balance of power is a comparison of the power at the input of the optical line with the losses in fiber optic cables and other path components. This will help to find the optimal parameters of transmitting and receiving devices to ensure proper signal transmission.

The example optical path employs ULTOMODE devices - Ethernet media converters ULTIMODE M-403M L11041.

Typical application of ULTIMODE L11041 Ethernet media converters

With the basic parameters of the devices (output power of the transmitter and sensitivity of the receiver), one can calculate the maximum distance of transmission over typical single-mode fiber.

The parameters necessary for calculation:

Additional assumptions:

The minimum distance (for minimum transmitter power) in the second transmission window is:
(P_tx1 - P_rx1 - P_m - P_s)/0.4 = (-5 + 25 - 5 - 1)/0.4 = 35 km

The maximum distance (for maximum transmitter power) in the second transmission window is:
(P_tx2 - P_rx1 - P_m - P_s)/0.4 = (0 + 25 - 5 - 1)/0.4 = 47.5 km

With the given assumptions, the transmission via single-mode fiber is guaranteed at least over 35 km distance. The input power depends to some extent on operating temperature and aging of the laser diode. The MTBF of the diodes employed in ULTIMODE optical devices is at least 100 000 hours, i.e. 11 years.
ULTIMODE media converters are reliable devices enabling the transmission of Fast Ethernet data stream in two single-mode optical fibers at distances up to 40 km. The media converter has two SC connectors used to transmit (Tx) or receive (Rx) the signal. Optical signal is transmitted and received in the second transmission window of 1310 nm.

Surveillance of POS - video text inserter.

A very important element for effective monitoring of stores, shops, petrol stations, etc. is detailed information from the spots where transactions take place, i.e. from points of sales (POS) and cash registers. Combining video surveillance with POS data, it is possible to check whether the product given to the customer is consistent with that on the receipt.
To have close supervision of all transactions, one can use POS Video Text Inserter FG-4 (M1720) which links point of sale terminal with CCTV cameras to produce a continuous overlay of transactions superimposed on video output. This allows to save complete information about sales.
The device supports POSNET and secondary protocols (Novitus, Innova). To connect the device to a POS printer, one needs RS-232 to RS-485 converter SNIF-42 M1721.

An example of POS data displayed on a CCTV monitor

HDMI switcher.

Signal HD HDMI Switcher 3x1 (H3131) enables the user to connect to a modern TV set equipped with HDMI input up to three sources of high-definition signals. The amplified output signal can be transmitted via HDMI 1.3b cable over distance up to 15 m.
It is an ideal device for connecting satellite receiver, DVD player, PC or game console to a television equipped with a small amount of HDMI inputs. Even when the TV has sufficient number of HDMI inputs, it may be more elegant to connect only one HDMI cable for easy installation on a wall with the use of LCD/plasma mount. It really improves the appearance of the TV suspended on the wall.
The choice of the device from which the signal is connected to the TV is performed with the included remote control.

Application diagram

Distinguishing features:

TP-Link &Windows 7.

The latest Windows 7 drivers for TP-Link devices are available at the manufacturer's site.

Fuji Sankei Building.

The headquarters of Fuji-Sankei Communications. The building houses the studios of Fuji Television. It has been built on the artificial island of Odaiba. Odaiba beginnings date back to 1850, when in Tokyo Bay there were created 6 small islands for deploying cannons for defense of the capital. At the end of the twentieth century, large investments have led to the expansion of the complex of islands. Already in the 90s, Odaiba had 100 000 inhabitants and a number of prestigious buildings connected with modern industry and tourism.

We have written about:

Problems with GSM coverage? The solution is use of SIGNAL GSM repeater - an installation example. The investor required to amplify GSM signals of two operators in shop floor in Krakow. Measurements at the plant showed a very weak mobile signals inside the shop floor. By contrast, the signals outside the hall were much better and allowed smooth conversations via mobile phones.
Due to large space to cover, the proper choice was SIGNAL GSM-300 repeater (A6760) with two indoor GSM antennas (A6800).

How to combine two SAT signals into one cable - TWINSENDER. A common mistake made when wiring houses and apartments (or installing a satellite TV system) is putting only as many cables as needed at the moment. Most of satellite dishes have been installed with single LNBs, each connected with the sat receiver via single coaxial cable. However, modern sat receivers with recording functions (PVRs) have two tuners that require two independent signals. The same is needed when one wants to use another receiver. To avoid the trouble with installing another cable, one can use the TWINSENDER R85260.

Camera for suspension ceilings - CAM 500 + IR M11255. In offices, conference rooms, private homes - an important role in the selection of the camera, in addition to its performance, is the look of the device.
If aesthetics is important, the best solution is camera mounted in suspended ceiling - easy to install and practically invisible (thanks to its shape and color).

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