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

Digital terrestrial television in the world. The main DTT standards are DVB-T, ATSC, ISDB-T, and DVB-T/H.
The most popular standard (in terms of the number of the countries and their area) is the European DVB-T. In most cases it is used for distribution of programs in standard resolution (SDTV). A second-generation DTT standard, DVB-T2, is planned for broadcasting HD channels. It is to be finally adopted next year, but many European countries have accepted this platform yet (e.g. Great Britain plans to transmit London 2012 Olympics just using this standard).
American ATSC is to be modernized, due to problems with mobile applications. ISDB-T is used in Japan and Brazil.
Among the existing standards the most advanced is the Chinese DMB-TH (Digital Multimedia Broadcasting - Terrestrial / Handheld). It is based on TDS-OFDM modulation (Time Domain Synchronous - Orthogonal Frequency Division Multiplexing), more advanced solution that OFDM used in DVB-T, not to mention of ATSC - 8VSB.
The new method of modulation, similarly to OFDM, allows multi-channel transmission, which is perfect for conveying large data streams, including HDTV. The system is also tested in South America (Venezuela) and Arab countries (Syria, Jordan).

DTT standards in the world (source: Wikipedia)

Telecommunications in Portugal. Portugal has 10.6 million citizens. There are 4.2 million subscribers of fixed telephone lines, and 12.2 million active cellular phones.
The number of Internet users is estimated to be 3.2 million (2006). The number of hosts (computers with permanent IP address) is about 836 000 (2007).
According to European Competitive Telecommunications Association, at the beginning of 2006 about 12.3% of Portuguese people had broadband access to the Internet.
At the same time the European leader was Denmark, with the percentage of 29%, whereas the figure was 4.4% in Czech Republic, 3,3% in Poland, 75% in the USA.
The leader of TV market in Portugal, both in the number of subscribers and in implementation of modern technological solutions, is TV Cabo. In 1999, TV Cabo supported by Motorola introduced broadband Internet in cable networks. It was also the first television platform in the world that started up interactive TV services (VoD, home banking, shopping - based on Microsoft TV Platform).
Portugal belongs to the small group of several European countries that have not launched digital terrestrial broadcasts yet. The start of DVB-T platform is planned for 2013, including terrestrial HD transmissions.

Telecommunications in Portugal

Focus hotel chain modernizes TV antenna systems. Important sports events can motivate hotel management to improve the quality of TV reception. Before Beijing 2008 Olympics, for the comfort of the guests, Focus hotel chain decided to increase the number of received programs and their quality.
One of the replaced components was the headend in the hotel in Szczecin, Poland.
INNEX, the company that was chosen to do this job, proposed to exchange the existing headend for TERRA MMH-3000.

Digital modular headend TERRA MMH-3000 is a compact headend solution for the reception of DVB-S and DVB-T programs for analog redistribution in SMATV and small CATV networks, e.g. in hotels, boarding houses, multi-family houses, housing developments. Thanks to vestigial side band modulators it allows to utilize adjacent channels. MMH-3000 can be installed in a standard 19" rack. The UC-380 base unit incorporates power supply, RF amplifier, and intelligent data bus. It may hold up to 8 individual modules - digital satellite or terrestrial receivers and RF modulators.

Main features of the MMH-3000 headend:

Due to capability of demodulation of multiple transponder streams, the complete stream is available as MPEG-2 TS (Transport Stream) at the dedicated output of QPSK CI Receiver RD-313C. It can be utilized by MPEG-2 TS Decoders/VSB Modulators DM-313 (R81712). It is an optimum solution for receiving several programs from one transponder, saving the number of QPSK receivers with CI modules.
The signals from the headend are amplifed by the set of ZG channel amplifiers from Alcad.
After the modernization there are available 32 channels (in all 128 outlets), among them 24 satellite programs.
The newest technology from TERRA and professionalism of the installation company were fundamental to meeting expectations and satisfying needs of the investor.

The Terra headend and set of channel amplifiers installed in Hotel Focus

ULTIMAX - DVRs for demanding customers - control with a mouse. ULTIMAX DVRs can be fully managed via computer network. With client program or even Internet browser, the remote users can have access to functions according to their access level (set by the administrator of the system). The functions include live monitoring, playback, PTZ control - all of them can be controlled with a mouse. It makes much easier to choose the desired options and functions. Most other DVRs available on the market enable the user to control with a mouse only menu options. In ULTIMAX DVRs there is possibility of choosing and controlling the main functions:

ULTIMAX has won a prestigious award - Gold Medal of Intertelecom 2008

Remote access to NVR servers. Remote access to video, from any place in the world, becomes a standard feature of modern video surveillance systems. The indispensable condition for good results, aside from broadband Internet access, is adequate software. The software can perform functions like live monitoring, playback, system control and configuration.
The examples of such software are NUUO and Netstation applications. The both software packages enable the users to get remote access to the system and its resources.
They also allow to control PTZ cameras (in real time) and play back the archives recorded on the NVR server. The main feature of the software packages is possibility of remote management of the whole system.
Of course, the basic condition is continuous Internet access. In the case of lack of allocated IP address for the system, the adequate ports of the router have to be redirected.
The remote access to the system can be provided through the client program or Internet browser. The administrator of the system can grant the users different access rights.

Comparison of megapixel cameras in difficult lighting conditions. Most megapixel cameras are based on CMOS sensors. These sensors usually have lower sensitivity than their CCD counterparts used in majority of professional standard-resolution cameras. But skilled setting of image parameters allows to get good quality even in adverse lighting conditions. Below there is a comparison of screenshots from ACTi ACM-5611 K1511 and other camera from a leading manufacturer, not equipped with night mode. The good quality of the image on the left is also the effect of optimum level of AGC and proper shutter speed.

New ADSL router TP-Link TD-W8901G. TP-Link TD-W8901G N2902 enables the user to share Internet connection supplied by a telephone operator in ADSL technology (Annex A). Its ADSL modem is compatible with ADSL/ADSL2/ADSL2+ protocols, and the Access Point can work in IEEE802.11b/g standards. The device has been also equipped with 4-port switch, and its WAN port (R11) is to be directly connected with phone line. An important feature of TP-Link TD-W8901G is possibility of using QoS control mechanisms.

TP-Link TD-W8901G offers a number of means for protection of WLAN:

• SSID hiding, enabling connections only for the stations with preset SSID,
• 64/128/152-bit WEP, WPA/WPA2, WPA-PSK/WPA2-PSK and TKIP/AES.

The TD-W8920G router is easily manageable with any web browser. The device needs only simple configuration and ensures very good stability.

ADSL2+ router TP-Link TD-W8901G
N2902 integrated with 4-port switch and Access Point

Quick Secure Setup (QSS). This function enables the user to configure the wireless network quickly and easily.
QSS can be exemplified by its application in TP-LINK TL-WR841N N3251. Pressing QSS button on the case of this AP and starting adequate driver of the wireless card also supporting QSS, the user begins automatic configuration of the link. The whole process takes about 10 seconds.

TP-Link devices with QSS function:

The LED indicator situated close to QSS symbol shows the status of configuration process:

Green blinking means proper conditions for establishing wireless link with QSS function (in process)

Continuous green light indicates that the configuration of wireless link with QSS has been successful

Red blinking means lack of wireless link - the QSS attempt ended in failure

Normally the QSS function makes the configuration of a new wireless device much quicker, saving the time of the home or SOHO user.

We have written about

9-cable system - multiswitch installations. The most flexible multiswitch installations in multi-story buildings are based on 9-cable system (signals from two Quatro LNBs and terrestrial TV antenna). On each floor we employ the splitter providing signals to multiswitches. It allows to shape the network according to actual requirements - we may deploy practically unlimited number of outlets...
- archive DWR of Jan. 14, 2008

Remote monitoring via Internet. Easy access to the Internet allows to distribute in the Web both live and archived video. Many users have access over ADSL links, without static IP addresses. In this case, to operate video servers it is indispensable to use DDNS service...
- archive DWR of Jan 14, 2008

How does DDNS work? Users of ADSL service (e.g. Neostrada in Poland) do not have a static IP - it is changed periodically. With this type of connectivity it is not possible to run a server, because the current IP address is unknown...
- archive DWR of Dec. 17, 2007

Index of published issues