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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 8/2010 (Feb. 22, 2010)
Vancouver has the Olympics and security. The Olympic Games are a very important event for the whole world. The organizers should create great atmosphere and provide a wonderful spectacle.
A very important element is the safety of both the athletes and spectators. The cost of securing this year's Olympics amounts to over 850 million USD. The main components of the security system are 900 CCTV cameras deployed in the Olympic village and the city. Most of the equipment has been supplied by Panasonic. There have been applied many vandal proof network fixed dome cameras WV-NW484S. These day/night IP cameras are equipped with WDR sensors (Super Dynamic III) providing resolutions of 540 TVL (color) / 570 TVL (B/W), which allows for accurate observation around the clock. The cameras are powered by PoE.
The CCTV cameras have been borrowed for the duration of the Games. After the event, most of them will be dismantled. The reason for adopting this approach is both the high cost of operating such a large installation and the attitude of the residents toward the system - they are afraid to be under too much surveillance.
Usually sports events of this rank as the Olympics are presented as a powerful factor in fostering the development of the region in which they take place. In the case of Vancouver, for the first time many inhabitants of such a "happy city" have not been satisfied with the organizational formula of the sporting spectacle. A large group of people think that great expenses borne by society become the source of profits for private companies, mainly TV stations and sports organizations. Many argue that the profits of local hoteliers and restaurateurs do not balance the costs of the necessary investments and the discomfort of the residents exposed to the controls relating to security. US$ 850 million spent on Olympic security is the amount sufficient to build several thousand apartments.
Vancouver has the Olympics and security, but for the first time none of them has been desired by a large group of residents.
Preparations for the Olympics
Radio links using untypical masts - where are they? In general, antennas of wireless links are situated on the heights of several dozen meters, so that radio waves are not suppressed by buildings and trees. The antennas in the photos below are mounted very low, just a few meters above the ground or roofs of low buildings.
Where are these antennas and why are they arranged in this way? - The answer at the end of this issue.
Radio links using untypical masts - where are they? -The answer at the end of this issue.
How to choose the components of a headend? TERRA headend is used for redistribution of TV programs, received both from satellites and terrestrial transmitters. It can also distribute audio/video signals from CCTV cameras, computers, DVD players etc. The RF modulator of each module can operate on any channel from the whole 110-862 MHz band (channels S1-69). Therefore, the subscribes do not need any additional equipment - they can use regular TV sets. In the case of large distribution systems (above 100 outlets) as well as in hotels, boardinghouses etc., the headend is usually housed in a 19" RACK cabinet. The VSB modulators in the modules are capable of working on adjacent channels, with output levels up to 102 dBuV, which allows to connect approximately 60 outlets without using additional amplifiers. When the distribution network is to have more outlets, there are needed channel amplifiers from the Alcad series: ZG (ZG-401, ZG-601, ZG-421).
The first step in the design of the headend is the choice of channels that are to be distributed in the network. The total number of the channels determines the quantity of the Base Units UC-380. One unit can house up to 8 modules. Each module distributes one channel.
The headend can be configured in Master - Slave mode, i.e. the programs broadcast from one transponder can be decoded in the QPSK CI Receiver RDC-313 R81710 which provides MPEG-2 transport stream (MPEG-2 TS) to cheaper MPEG-2/PAL transmodulators - DM-313 R81712. It is an optimum solution for receiving several programs from one transponder, saving the number of QPSK receivers. One RDC-313 receiver with PowerCam Pro CA module allows to decode up to four channels.

More detailed information on this subject can be found in A short guide to MMH-3000 TERRA design .

In the diagram above the signal from a QUATRO LNB comes into RD-313C R81710 module which provides MPEG-2 TS to three DM-313 R81712 decoders.
On the right side of the power supply there are four RD-313C R81710 receivers. Three of them use the same combination of band/polarization, so they can be connected in series (RF loopthrough); the last one uses different signal (another band/polarization combination).
SMATV system in a multi-family building - TERRA multiswitches. The customer's requirement was to make SMATV installation capable of distributing terrestrial TV programs, FM radio stations (88-108 MHz), and satellite signals from two satellites, Hotbird and Astra.
The task was undertaken by TECH-SAT from Katowice, Poland.
The antenna array consists of UHF antenna ATX-55, VHF antenna ATZ-5, and omnidirectional FM antenna A0210. The satellite signals are received via aluminum dish Famamal A9662 equipped with two LNBs - Inverto QUATRO Red Extended A98257.
In TPR metal box inside the building there are placed two active components: Universal Multiband Amplifier Telmor WWK-861 R89860 and multiswitch TERRA MSR-908 R70808. TECH-SAT company has also protected the installation from the effects of lightning discharges through the use of TV-Sat surge protectors Signal R48602 at the inputs of the active devices.
The active devices work properly and the signal levels in all outlets ensure quality reception of all available programs. Each outlet is connected with two outputs of the multiswitch. Use of the 9/8 Terra MSR-908 multiswitch with eight outputs allows to provide signals for up two four PVR receivers.
View of the antenna array
View of the TERRA MSR-908 R70808 multiswitch and Telmor WWK-861 R89860 amplifier in the TPR box
Building blocks of the network - SFP transceivers. FTTH solutions should ensure flexibility for possible future changes, usually extensions of the system due to growing number of subscribers. In such situations the best hardware solutions are provided by media converters with SFP slots allowing to use a variety of SFP modules/transceivers.
An example is the media converter ULTIMODE M-100G/SFP L1301 with SFP slot for optical modules compliant with IEEE 802.3z 1000Base-FX standard. In the case of expansion of the network - including topology change and even involving different power budget of the optical interconnection system - it is enough to replace the SFP module only, and not the entire device.
SFP (Small Form-Factor Pluggable) are transceiver modules used in telecommunications for data conversion and transmission. They are widely used in switches, routers, media converters. SFP modules (also known as Mini-GBIC) are designed for SONET, ATM, GigabitEthernet, optical networks. SFP interface has been standardized by the manufacturers under the Multi-Source Agreement (MSA). The interface is the the successor of GBIC and allows greater port density.
Ethernet Media Converter: ULTIMODE M-100G/SFPSFP Transceiver: ULTIMODE SFP-203G (two single-mode fibers up to 20 km)SFP Transceiver: ULTIMODE SFP-203G (two single-mode fibers up to 20 km)Ethernet Media Converter: ULTIMODE M-100G/SFP
Media converter with SFP slot + SFP transceiver
M-100G/SFP L1301 media converter cooperates with the following GbE SFP modules:
Type of optical fiber:multimode
Transmission range:2 km
20 km
Transmission speed:1.25 Gb/s
1.25 Gb/s
Wavelength (Tx/Rx):1310/1310 nm
1310/1550 nm
1550/1310 nm
Connectors:2x LC2x LC1x SC1x SC
Wireless CCTV systems - good practice guidelines (part 1). Wireless transmission is increasingly popular in remote monitoring of dispersed locations, for several reasons:
  • possibility of longer links than in the case of using UTP/FTP cable,
  • fast and inexpensive installation comparing to any cable systems,
  • in the case of wireless digital transmission systems - satisfactory resistance to interference.
However, some issues need specific attention. The first one is the bandwidth of the wireless transmission. Since wired transmission systems transmit data simultaneously in two directions (Full Duplex), the Fast Ethernet link (100 Mb/s) achieves in practice the transmission speeds of 70 Mb/s in each direction.
The wireless technology has to share the transmission channel, so it alternates the direction of the transmission (Half Duplex). In the case of 54 Mb/s link, the maximum practical throughput can reach 25 Mb/s in each direction. This is the maximum value that can be significantly reduced due to the length of the link, poor mutual visibility of the antennas, coexistence of other WLANs in the area, significant electromagnetic interference. 54 Mb/s link allows to transmit digital data from up to eight ULTICAM DS-852MF-E K1441 2 Mpx cameras with maximum resolution, at 12 fps.
Wireless Access Point: ULTIAIR 423KC
ULTIAIR N2301 access point
allows to transmit video streams
at speeds up to 25 Mb/s
Gold Medal of Alarm Kielce 2009
for ULTIAIR devices
New DVRs from the world leader - HIKVISION/ULTIMAX. HIKVISION company is the pioneer of H.264 compression in digital video recorders. It has been included into the group of 50 most promising undertakings in the field of advanced technologies in China (the Deloitte ranking). DIPOL company has introduced to the offer the latest HIKVISION DVRs.
A new generation of the recorders is based on newly developed Texas Instruments processors using DaVinci technology. This allows to stay ahead of competition in the development of "intelligent software". The possibilities of the processors multiply the functionality of the new DVRs, new applications can be loaded along with software updates.
HIKVISION DVRs have been known on the Czech, Hungarian, Polish and Slovak markets as ULTIMAX series. The network software is compatible with the older and new series of ULTIMAX and HIKVISION DVRs, while the firmware from the new series cannot not be uploaded to the predecessors.

The newly introduced HIKVISION DVRs have been divide into three series - 73xxHI, 81xxHDI and 81xxHFI. Each of them is designed for different types of customers: from small shops and houses, through medium-sized businesses, up to the largest and most advanced monitoring systems with dispersed locations (warehouses, public space, stadiums, large enterprises, cities).
HIKVISION/ULTIMAX DVRs of 73... and 81... series
The recorders have all features that are important for the users and have been thoroughly tested in the previous series:
  • H.264 compression,
  • adjustable bitrate, frame rate, recording quality,
  • SATA interface,
  • possibility of connecting hard drives with a total capacity of 16 TB,
  • possibility of mounting additional accessories (e.g. DVD writer),
  • control via mouse, remote control, dedicated keyboard, buttons on the front panel.
Many new features include:
  • clear graphical menu displayed at a resolution of 1280 x 1024,
  • new external design: USB port on the front panel and "Jog dial",
  • even more stable operation,
  • D1 (4CIF) recording even in the lower models,
  • simultaneous monitoring of up to 16 channels,
  • fast selection of any time point by using the timeline,
  • excellent work on the Internet,
  • VGA output (resolution up to 1280x1024, refresh rate 60Hz) - clear, sharp images
  • solid housing, high-performance local keyboard and accessories.
Application diagram of HIKVISION/ULTIMAX DVRs
Our offer includes 4-channel model (M74040), 8-channel models (M74080, M76080, M78080) and 16-channel models (M74160, M76160, M78160).
Coverage problems have gone away - application of GSM amplifier/repeater. The investor had problems with GSM signal in the entire three-story recreational building Pokoje Pod Lasem (Rooms on the Forest) in Koscielisko, Poland. Due to location in a valley, the signal inside the building was very weak and often faded. The most important room, in which the GSM signal was to be strengthened, was the office located in the basement of the building.
The installation has been designed and carried out by "Impuls" company from Zakopane, Poland. The system employs Signal GSM-1200 repeater A6780, outdoor antenna ATK-10 850-960 A7015, antenna mount E8735C, panel antenna Trans-Data 7.5-10 A741020, two-way GSM splitter A6812 and Tri-Lan 240 cable E1171.
The GSM repeater has been installed in the attic. The panel antenna has been mounted on the beam of the roof structure, with its front side down. Due to a very low signal level outside the building, the company has installed the ATK-10 A7015 external directional antenna. All components of the installation have been connected with the Tri-Lan 240 E1171 cable. The installers effectively used shielding properties of the tin roof, which allowed to place the two antennas in proximity to each other. To increase the signal level in the basement, there have been used two-way splitter and the internal antenna supplied with the repeater.

In this way there has been achieved full coverage with all available cellular networks throughout the building.
GSM Antenna: ATK 10/850-960MHz (10-element)Antenna support WG-5 (SAT/TV, 35 x 110 cm, galvanized)GSM Repeater Signal GSM-1200Two-way GSM SplitterGSM/DSC/UMTS Antenna: TRANS-DATA KPV7.5/10
The investor is fully satisfied with the effects provided by the repeater and with aesthetics of the installation.
View of the ATK-10 A7015 outdoor antenna
View of the A6780 repeater and A741020 indoor antenna
Close-up of the Signal GSM-1200 A6780 repeater
N connectors in WLAN systems - installation instructions. Connectors used for antennas mounted on the outside of buildings should have adequate protection against water. This is a fundamental issue, because a bit of water that penetrates the connection will cause significant (even tens of percent) increase of the dissipated power, simply turned into heat.
In principle, the only connectors suitable for these applications are N-type connectors - designed for military marine applications. The N-male connector E84130 has been designed for use up to 6 GHz with Tri-Lan 240 E1171 or H-155 cable.

The main parameters of connectors which should be noted because they are essential for the transmission, are:
  • Voltage standing wave ratio (VSWR) saying about how much of the incident RF power is reflected back to the source of signal (transmitter). This parameter should not exceed 1.5, which corresponds with reflection of ca. 4% of the signal's power. In the case of N connector E84130 this parameter amounts to 1.3.
  • The same feature of connections (impedance matching) can be expressed by return loss (RL), denoted in decibels (dB). It even more explicitly shows how much of the RF power returns to the power source (greater value of this parameter means better matching). For 2.4 GHz installations this parameter should exceed 15 dB (N connector E84130 and Tri-Lan cable - 18 dB);
  • Insertion loss (IL), saying about power loss in the connection, in the case of E84130 below 0.5 dB at 2.4 GHz.
The connectors of this series are used in installations operating in 2.4 GHz and 5 GHz bands. They fill in the gap between cheap, low quality no-name connectors and very expensive top-brand equipment.
N-plug on Tri-Lan 240 coaxial cable - Installing
N-plug on Tri-Lan 240 coaxial cable - installing procedure
Greece. The antennas shown in the pictures are parts of wireless links used to provide communications between islands - there are no obstacles between the pairs of the antennas so they are not placed high.
A water heating facility, satellite dish and terrestrial antenna
mounted on turntable - is a common view of a Greek house
We have written about:

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The spectrum of DVB-T signal differs from the spectrum of a single analog channel, which is presented in the following figures. The challenge for the amplifier to increase the level of the DVB-T signal is well visible there. Due to steep slopes and use of subcarriers in the whole width of the channel (usually carrying a whole multiplex), the key parameters of the amplifier become flat gain across the channel and selectivity...
George Popescu
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