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

Digital broadcasting in Poland. In Poland, there is planned DVB-T broadcasting in MPEG-4 system. Current tests are carried out both in MPEG-2 and MPEG-4. The former ones have been performed for several years now. There is a group of several thousand people who receive these programs. The MPEG-4 broadcasts are currently received by several hundred people only.
More and more countries choose MPEG-4 system for DVB-T broadcasts, having in mind development of HDTV. Among them there are Norway, Estonia, Slovenia, Lithuania, Latvia and Hungary.

Digital programs from transmitters in Warsaw and Srem. (according to: Forum TP-Emitel)

Antenna system measurements. Knowledge of signal parameters, among others:

allows to prepare optimal design and verify actual results - to do quality installation.

We can recommend for every installer the suitable measurement set: TM-3000 R10502 - for measuring terrestrial signals, and DSM-100 R10813 - for satellite broadcasts and installations.

TM-3000 R10502 can measure or provide:

DSM 100 R10813 can measure or provide:

Bit Error Ratio (BER). BER is the parameter indicating possibility and quality of reception of digital broadcasts (e.g. with QPSK modulation, used for DVB (Digital Video Broadcasting).
Practically, the ratio has to be lower than 10^-3 to enable any reception, whereas the level 10^-9 guarantees ideal transmission (C/N - carrier-to-noise ratio - is adequately equal to 7 dB and 12 dB).
Error rate 10^-9 means that only one in a billion of transmitted bits may be misrepresented. Due to Forward Error Correction (FEC), the BER value ensuring correct reception is changeable.
Measurements of BER parameter can be performed with a meter having this function. BER is interdependent with C/N, but in practice actual characteristics of specific devices, being very difficult to estimate, makes such an assessment inaccurate.

C/ N [dB]	BER	Quality of transmission
5.0	10-3	unacceptable
8.0	10-4	inadequate
10.5	10-5	satisfactory
11.7	10-6	good
12.3	10-7	very good
12.8	10-8	excellent
13.2	10-9	ideal

Large multiswitch installations - still the mainstream of SMATV systems. All experts think that large multiswitch installations - for dozens or more subscribers - will be in demand for years to come. Customers who buy Full HD televisions expect to get adequate quality TV signals, to take full advantage of the new equipment. Terrestrial HDTV broadcasts are not very probable in the near future, whereas the offer of commercial satellite TV providers is still being extended. In newly built apartment houses it is usually not allowed to mount satellite dishes on elevations. Because there is currently no standard or dominating platform of HD headend stations, most of the buildings are equipped with multiswitch installations.
Using multiswitches from MS, and MSR series and the amplifiers from SA family, it is possible to do installations up to 200 outlets.

Multiswitch installation with 20 outlets.

Monitoring system in Ford museum. A tourist attraction of Mexican city Tampico is undoubtedly the museum in which visitors can be impressed by the legend of American automotive industry - Ford Mustang cars. The value of the exhibits is not only aesthetic and historical - that's why the trustee of the museum decided to protect the collection by modernizing the existing monitoring system.
The new video surveillance system is based on ACTi cameras - ACM-1431 K1118 and CAM-6500N (CAM-6610 K1214 - version for indoor applications). The former camera is equipped with IR illuminator allowing to monitor the area even in complete darkness. For recording video data and remote viewing of the protected areas there is used software package NVR K3032, enabling the operator of the system fully utilize potential of the modern devices.

Exhibits in Ford Mustang museum in Mexico

Concept of the monitoring system

Posting pictures from IP PiXORD devices on a website, using ftp server. The precondition for presentation of CCTV images on a website is adequate upload capacity of the Internet connection. To depict the problem - one user connected with the server providing full D1 images at 25 fps with MPEG-4 compression, when setting variable bit rate mode, will require 384 kbps for static image and even up to 3.5 Mbps for dynamic action. If the website is to be available for large number of visitors, the parameters should be adequately multiplied.
An economical method of overcoming these problems is posting pictures by entering into html code of www site commands of downloading pictures from ftp server in certain periods of time. All devices of PiXORD can send CCTV pictures or video on ftp server.

Vandal-proof cameras. CCTV cameras installed in reformatories, penitentiaries, or even "normal" schools should meet special requirements. Firstly, the cameras have to be resistant to intentional damages, but secondly - they should not cause any risk for the people in charge or students.
Such requirements are fulfilled by M10746 cameras. The body of the housing is made of metal, the dome of polycarbonate. The housing is secured by special patent lock. Both in the case of placing the camera on a ceiling and wall there is possibility of concealing the connecting cables.
The camera is oval in shape and easy to clean. The built-in IR illuminator allows operation even in complete darkness. The manufacturer adds wall bracket.
The camera is fully prepared for use in monitoring systems in schools, being deployed in large numbers there. It is also recommended for mounting in staircases, housing developments, underground parking lots.

Honorable mention for TP-LINK router - TL-WR543G N2955. Independent Czech magazine Computer World honored TP-Link family as "Product of the Year". The editorial staff has particularly emphasized stability, range of operation, and security capabilities of these WLAN products. TL-WR543G N2955 has become one of the most popular WLAN devices in the European market. It is worth to underline that it is not the first distinction won by this brand, the representative of which in the Polish market is DIPOL.

TP-LINK TL-WR543G N2955 integrates access point, broadband router (to connect xDSL service or cable modem), and 4-port FastEthernet switch.

The main features of TL-WR543G:

TP- Link TL-WR543G N2955 has been designed for two modes of work: AP or AP Client with routing (WISP mode - Wireless Internet Service Provider). The latter mode is very useful when the Internet connection is provided wirelessly.

Twisted-pair cables in CCTV. Standard transmission lines used in analog CCTV monitoring systems are made with coaxial cable. However, due to growing popularity of IP cameras and possibility of easy migration to digital system, in many installations there are used UTP/FTP cables...

We recommend the article >>> Video signal and audio signal transmission via twisted pair cable - with power option