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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 6/2008 (Feb. 11, 2008)
DIPOL website in Hungarian. Mi vagyunk az európai disztributorai a CCTV, WLAN, TV-SAT gyártók kommunikációs - televízió - és rádióantennáinak. Ajánlatunkban több, mint 1200 termék szerepel gyors, egyszerű megrendelés és kiszállítás.
We are pleased to announce the availability of the Hungarian version - it is the next language after Polish and English. Our partner in Hungary is Ostel - Invest company, based in Debrecen.
This website can be found on www.dipol.com.pl after selecting Magyar (in the upper right corner), or directly at www.ostelsat.hu.
Lengyel, magyar - két jó barát, egyűtt harcol és issza borát :-)
Pole and Hungarian are two brothers, they fight and drink their wine together
Turbo speed in mobile communication - 4G LTE. Last December Nokia carried out tests of 4G LTE technology (Long Term Evolution).
The base station was installed at the top of the Heinrich Hertz Institut building in the center of Berlin, whereas the mobile terminal was placed in a moving car, about one kilometer away. The download speed reached 173 Mbps. The system worked at 2.6 GHz.
The first GSM specifications had allowed only 9.6 kbps. The next solution was High Speed Circuit Switched Data (HSCSD) which enabled the users to enjoy the amazing speed of a fixed-line modem - up to 57.6 kbps.
A new era of mobile transmission technologies has begun since ... the commercial failure of GSM 3G, or UMTS. The related technology that has been developed - cheaper and ensuring better results - is called HSPA (HSDPA, HSUPA) or GSM 3.5 G. The HSDPA standard offers throughputs up to 14.4 Mbps.
LTE is the newest transmission system for mobile applications, developed according to the 3rd Generation Partnership Project (3GPP). LTE networks will offer much higher capacities that current WCDMA/HSPA systems. The specification accepted in January, 2008, adopts theoretical limit of 326 Mbps. The mobile terminals will use OFDM modulation for downlink and SC - FDMA for uplink. The bandwidth of the transmission channel will be varied from 1.5 to 20 MHz.
The technology utilizes multiple-in, multiple-out antenna concept (MIMO), the same as the newest 802.11n Wi-Fi networks.
Antennas used in MIMO systems
German radar stations during WWII. Among several solutions used by Germans the most popular was the "Himmelbett" radio system - consisted of two FuMG 65 "Würzburg-Riese" radars, Freya radar, and main Seeburg station.
The Freya radar had a maximum range of about 200 kilometers and was used for observation, in concert with two gun laying radars - "Würzburg-Riese", directing fighter squadrons at the arriving bombers.
The maximum range of FuMG 65 was 70 km. The radars were manufactured by Telefunken and equipped with antennas of 7.5m diameter.
In total there were about 1500 such stations in Europe. Many of them were deployed in occupied Poland, mainly in the north and south.
In our times we can only encounter characteristic concrete foundations in hexagonal form. They were the bases for the metal constructions of FuMG 65 weighting nearly 20 tons.

Additional photographs are available at these Polish sites:
Stacja Kondor, Remains after radars in southern Poland
Kozieglowy in Silesia, Poland. The concrete base for German radar - Luftwaffe FuMG-65 Würzburg-Riese (1/2). Funkmeßgerät Stellung 2 Ordnung Wartenstein
New generation of satellite transmissions - DVB-S2. The currently most popular system of satellite transmissions - DVB-S/MPEG-2 - allows to transmit from one transponder (38 Mbps) 7 SDTV programs. New system based on DVB-S2/MPEG-4/AVC standard widens the capacity up to 26 SDTV or 6 HDTV channels..
DVB-S2 employs the latest coding technique - LDPC (Low Density Parity Check), allowing transmissions with QPSK, 8PSK, 16APSK and 32APSK modulations.
The new standard is backwards compatible with DVB-S, enabling the owners of older terminals to use them for reception at the normal quality level.
Application of DVB-S2 allows increase of average data transmission rate by about 30%. There may be used both MPEG-2 and MPEG-4/AVC compression methods.
In Poland the change has been initiated by "n" platform.
It is important to notice the issue of distributing 8PSK signals in community installations (SMATV systems). There are no problems with multiswitch systems - the most popular solution used in satellite installations. In the case of IF/IF conversion the installer has to make sure that the IF/IF converters he wants to use are capable of conveying 8PSK signals - if it is needed. For example - the tests of UC-221/222 channel converters showed that they cannot be used with 8PSK transmissions (they are dedicated for QPSK and analog signals).
Constellation diagrams for QPSK and 8PSK
Multiswitch system for demanding users - reception of programs from 4 satellites.. Most of implemented multiswitch systems enable the users to receive programs from one or two satellites. There are situations where the contracting party (building developer, owner of a hotel etc.) wants to ensure access to more satellite positions.
Signal multiswitches allow to distribute programs from four satellites. Apart commonly used Hotbird and Astra, they can provide broadcasts e.g. from Sirius (Russian programs) and Hispasat (Spanish programs). Such installation in apartment building does not increase significantly the total cost and improves the standards, especially when foreigners make a certain part of the residents or guests.
Signal multiswitches are available is several versions: 17/4 - R694495, 17/6 - R694496, 17/8 - R694499, 17/12 - R694497, 17/16 - R694498. Every multiswitch is powered with R694494 AC/DC adapter (to be bought separately).
VHF TV Antenna: DIPOL 7/6-12 (7-element)Universal FM Antenna: DIPOL 1RZ B/PM (H/V))UHF TV antenna: DIPOL 19/21-69 DIGITALAntenna Triplexer - ZA 4MBroadband RF Amplifier: Alcad CA-215Multiswitch: Signal (17-input, 8-output)TV/SAT Wall Plate: Signal R-TV-SAT (terminal)
Signal multiswitches allow to receive programs from four satellites
Collection of satellite dishes from DIPOL has been described in well known Polish monthly magazine for professionals and amateurs - Radioelektronik.
Satellite television is experiencing its second youth, thanks to technical capability of distributing high-definition TV programs.
The last year in DIPOL - the article in "Twierdza" (The Fortress) In the first 2008 issue of the magazine Ms. Magda Stachula from our Marketing Department gives an account of DIPOL's undertakings and accomplishments in 2007.

Last year we saw increased interest in city surveillance systems, especially in small towns. Use of wireless transmission technology allowed to simplify the design and lower the costs. Properly designed wireless systems were fully operational. It seems that 5GHz implementations, supported by MESH technology, are really effective solutions for small towns. Larger systems require use of licensed bands. Unfortunately the hopes for quick use of WiMax for CCTV purposes have not been fulfilled.
The year 2007 brought record turnover and increase of sales volume in the field of IP CCTV. We saw consolidation of market position of several companies, first of all: ACTi, IQinVision, Pixord. In cooperation with teams of designers and installation companies, DIPOL took part in building monitoring systems in eight Polish towns, as well as in interesting projects on Iceland, Cyprus and in Italy.
Video Surveillance of Cities - in this case of Opatow, Poland. The monitoring system is based on wireless transmission and IP cameras from ACTi.
Our participation in trade fairs - Intertelecom, Sat Krak, and ALARM - has been a great success. The lectures given by our engineers drew huge audiences. The products demonstrated by DIPOL won medals at ALARM in Kielce (Megapixel camera - IQinVision), and SatKrak in Krakow (TRISET cables).
A positive thing was strengthening of the market position of our branches in Germany, Hungary, Slovakia and the Czech Republic.
An important issue for our company was change of the logo. The new logo has achieved widespread acceptance by our customers and partners.
A great success is also the new website - it is among the 100,000 most popular WWW sites in the world.
To make a long story short - the 2007 year was tremendously exciting and rewarding. We fulfilled strategic marketing and sales plans, which has improved our market position in the fields of satellite TV and video monitoring (CCTV).
Making an effort to meet customers' needs we still widen the range of offered products and keep high performance level.
What will 2008 bring? We suppose there will be an intensive discussion and the first decisions about new video surveillance systems in stadiums and other sports facilities - due to preparations for UEFA EURO 2012 - the 14th European Championship for national football (soccer) teams. It is planned to have new or modernized stadiums and infrastructure - IP CCTV systems allow effective monitoring of dispersed locations as well as give possibility of managing large number of cameras that are needed in large stadiums. Our company has prepared a wide range of modern and well-tried devices.
Testing LAN cabling. Improper or unstable connections are the main reasons of problems with LAN installations. The problems begin with bad cables or improper termination. The N7050 cable tester helps installers to build LAN systems and service existing networks. It tests cable continuity, detects shorts circuits and incorrect connections. The device can be used for UTP/FTP cables terminated with RJ-45 connectors or for 50 ohm coaxial cables terminated with BNC plugs.
The set consists of two parts - the master and remote part (terminator) - that are used at the opposite ends of the tested cable. The LEDs show the results of the testing (order of lighting).


Cable Tester (RJ-45, BNC)
LAN cable tester - indispensable during installation
High Availability Systems. Data loss is one of the most widespread and costly security problems facing companies. The research shows that 50% of the companies that were affected by a major loss of data immediately went bankrupt, the next 40% suffered the same fate within two years. The proper planning of business continuity requires to include Disaster Recovery strategy and High Availability (HA) systems.
The main feature of these systems is adequate level of redundancy. The redundancy is achieved through replication of logical disk volumes onto separate physical hard disks in real time (disc mirroring) and additional links and network interfaces. It is important to use uninterrupted power systems (UPS) and eliminate single points of failure (SPF) - the critical points that could stop operation of the whole system.

One of the most popular methods of achieving greater performance and reliability through redundancy is RAID technology (Redundant Array of Independent Disks, or Redundant Array of Inexpensive Disks). There are several RAID levels - for example RAID1 makes an exact mirror copy, whereas RAID5 uses exclusive disjunction (XOR) - upon drive failure, any subsequent reads can be calculated from the distributed parity, e.g. with 5 disks of the same size only 20% space is needed for complete data protection (in the case of one drive failure).
Improvement of service availability demands that companies and organizations have to use high-availability clusters (failover clusters) - in case of computer failure. HA clusters usually use a heartbeat private network connection which monitors the health and status of each node in the cluster. If the server with a particular application crashes, the application is immediately restarted on another system without requiring administrative intervention.

Some additional information you can find in this page
Kilobytes, kilobits - the old problems with nomenclature. The units for measuring data transmission speed seem to be very similar, so they are often being confused. Many people do not distinguish between Kb/s and KB/s, kb/s and Kb/s. To clarify the problem we explain the rules of nomenclature for these units:
  • k 103, "kilo", 1000 units
  • K 210, 1024 units (the prefix commonly used in the field of computing, corresponding with binary systems)
  • b bit, the smallest unit of information, 0 or 1
  • B byte, group of eight binary digits, capable of representing 28 (256) states
so,
  • kb/s 1000 bits per second (1000 b/s or 1000 bps)
  • Kb/s 1024 bits per second (1024 b/s or 1000 bps)
  • kB/s 1000 bytes per second (8000 b/s or 8000 bps)
  • KB/s 1024 bytes per second (8192 b/s or 8192 bps)
Is it really defective? - part 2. Every router and access point has a default IP address set by the manufacturer, allowing to find the device in the network. When configuring the local network the user can or even should change it for a specific one. If he forgot the address, he wouldn't be able to log in. But there is a rescue procedure - hard reset of the device, which restores the default settings.

The reset is usually performed by pressing special "Reset" button for several or more seconds (to avoid an accidental action), mostly placed on the back side of the device. The complete reset procedure can take up to one minute.

Reseting procedure of TP-LINK devices provides additional protection against unintentional operation. The reset consists of four steps:
  • switching off the power
  • pressing down the "Reset" button while switching on
  • releasing the button after 10s from the moment of power on
  • waiting a while for completion of the reset.
Router TP-Link TL-R860 (8 LAN / 1 WAN ports)
The router TP-Link TL-R860 N2990. The RESET button can be found close to WAN port (on the right)
It is unacceptable to switch off the device when the resetting procedure has not been completed - carries a lot of risk for the circuitry.
CCTV course - Wroclaw, March 3, 2008. We invite everyone interested in "How to set up a CCTV system - a short course for beginners" (held in Polish).
The participants will learn about how to make their own CCTV systems.
More information
We have written about:

LAN with wireless connectivity to the Internet. There are many cases when several LANs (e.g. in office and warehouses, in several houses etc.) should be grouped into one network with Internet connectivity....
- archive DWR of Jan. 21, 2008

Outdoor (IP66) Day/Night IP camera with IR illuminator - Pixord P428. P428 K1136 is the first outdoor IP camera for all seasons from PIXORD. The camera module has been placed in watertight IP66 aluminum housing equipped with 230VAC/12VDC adapter, heater and fan.
- archive DWR of Jan. 7, 2008

Monitoring of schools - tapping not allowed. Gazeta Prawna (translation: Law Newspaper) has published the interpretation of Polish ombudsman Mr. Jan Kochanowski on sound recording issue in monitoring systems installed in schools...
- archive DWR of Nov. 11, 2007

Index of published issues.
Tri-Lan 240 - 50 ohm coaxial cable for WLAN systems, operating up to 6 GHz
 
George Popescu
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