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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 31/2009 (Sept 28, 2009)
The IEEE 802.11n standard ratified! The 802.11n standard, allowing for data transmission with rates up to 600 Mbps, is planned as the base for home multimedia transmissions.
The equipment based on the new standard has been available on the market for several years, but is really popular after the introduction of the "Draft 2.0", i.e. the set of requirements consistent with the planned target version. This allowed manufacturers to offer devices compatible with final standard.
Initially, the n-like devices operated at speeds up to 100 Mbps, and products of different brands did not work together. With progress in technology and standardization, the speed was increasing, and devices from different manufacturers were becoming compatible.

Cooperation of 802.11n devices with previous products:
  • 802.11b devices (CCK modulation) and 802.11g devices (OFDM modulation) operating in 2.4 GHz band with 20 MHz channels.
  • 802.11a devices (OFDM modulation) operating in 5 GHz band with 20 or 40 MHz channels.
Transmission speeds of up to 600 Mbps require the use of multiple channels simultaneously. Despite the application of a safeguard mechanism, the transmission is susceptible to interference from networks based on other standards, in particular 802.11 b/g.
Wireless 802.11n Draft 2.0 Mini-PCI Adapter: TP-Link TL-WN861N (300Mbps)
Access Point 802.11n (draft 2.0): TP-Link TL-WR941N <br />(300Mbps, built-in router and 4-port switch)
802.11n Draft 2.0 Mini-PCI Adapter
TP-LinkTL-WN861N, 300 Mbps
Access Point 802.11n (draft 2.0) TP-Link TL-WR941ND
with built-in router and 4-port switch, 300 Mbps
"Engagingly about antennas" - the last days for sending photos to the contest. At the end of the competition we get true gems of "antenna art".
We look forward to your entries till September 30.
We invite you to familiarize yourself with the entries that we have received so far.
More pictures>>
Antenna with better reception
Marcin Saletra

Tomasz Lis
Signal - new line of radial multiswitches. There is a change in our offer for small and medium SMATV systems. The new family of multiswitches ensures better quality of the devices that allow distribution of satellite and terrestrial signals in one-family houses and small apartment buildings. The series includes the following models:
9/12 Multiswitch: Signal MP-0912<br />(active terrestrial TV)
9/12 multiswitch Signal MP-0912

Operating parameters of the presented devices are similar to those of a higher-class equipment. The most important include:
  • very good isolation between inputs, both between satellite ones and between terrestrial TV input and satellite inputs (30 dB, 28 dB),
  • very good isolation between H and V polarizations (at least 30 dB),
  • high maximum output levels (101 dBuV for satellite signals and 85 dBuV for terrestrial TV signals).
The multiswitches pass DiSEqC 2.0 and ToneBurst control signals. A typical application of R6944804 multiswitch is shown in the diagram below.

The aim is to provide signals from Hotbird and Astra satellites and terrestrial DVB-T and analog TV stations to the three outlets (one of the receivers has double tuner and features PVR function - this requires a reservation of two multiswitch outputs).
Subscriber Terminal Outlet:Signal RTV-SAT-R (return path)TV/SAT Wall Plate: Signal R-TV-SAT (terminal)TV/SAT Wall Plate: Signal R-TV-SAT (terminal)HD DVB Receiver: FERGUSON HF-8900 HD9/4 Multiswitch: Signal MP-0904<br />(active terrestrial TV)Compression F Connector: PCT TRS-9 NT<br />(for TRISET-113) UHF TV Antenna: DIPOL 16/21-69 DVB-TUniversal QUATRO LNB: Golden Interstar 0.2dBOffset Satellite Dish: 90cm, galv. paint. A-EE1015DVB-S/T Receiver: Ferguson Ariva HDcombo
Example application of the Signal MP-0904 multiswitch (R6944804)
The simple system shown above is based on radial Signal multiswitch that can distribute DVB-S/S2 digital satellite programs (including HDTV) and terrestrial digital (DVB-T) and analog TV broadcasts. Currently, due to the growing popularity of DVB-T platform, manufacturers equip TV sets with digital terrestrial tuners. If some television has no built-in DVB-T tuner, the user can employ an external device (Set-Top-Box), e.g. Ferguson FT-8300 HD, or - like in the example above - Ferguson Ariva HDcombo A99381 (DVB-S and DVB-T receiver).
FHSS - a few words on WiFi - part 5. FHSS (Frequency Hopping Spread Spectrum) is another physical layer of the IEEE 802.11 standard.
The frequency of the carrier wave in FHSS is periodically (in regular time intervals) changing by discrete values (using a pseudorandom sequence known to both the transmitter and receiver). The time period when the frequency is constant (dwell time) is sufficient for sending several data bits. The consecutive carrier waves are modulated with frequency shift keying, which results in narrow-band signals.
The list of frequencies of the carrier wave is called frequency-hopping code (FH). The spectrum of such a signal, observed for the time longer than the period of the FH sequence is a set of discrete bars that can bypass the frequencies of interfering signals.
The advantage of FHSS systems is the possibility of retransmission of distorted messages at different frequencies in subsequent jumps. As mentioned, before the data transmission can take place, the transmitter and receiver must adopt the same hoping pattern, i.e. the sequence of channels that will be used during the transmission. If one of the channels does not allow proper communication (because of interference), the data transmission is continued on another frequency in the next jump/s.
Frequency Hopping Spread Spectrum
In the case of FHSS, the IEEE 802.11 standard provides 79 carrier frequencies (channels) with 1 MHz spacing, from 2402 MHz to 2480 MHz. Each of these carriers is modulated using GFSK. Possible transmission speeds are 1 Mbps and 2 Mbps. 78 strings of hoping sequences have been defined. The sequences have been further divided into 3 subsets with 26 strings. Sequences from the same subset can be assigned to systems that are close to each other. Because they are grouped together, the probability of collision is minimal. In theory, up to 26 systems can exist close to each other, but in practice, due to the number of collisions, about 12 is considered as a safe number. An important factor is the minimal difference between the momentary frequencies in different systems. Due to the limitations in selectivity of receivers, the difference should not be less than 6 MHz.
Faster Internet - ULTIMODE media converters. Ethernet media converters allow to change electrical signals (Ethernet data stream) coming via typical STP/UTP cables into modulated light signals transmitted via fiber optic cables, with data rates up to 1Gbps.
The ULTIMODE media converters are fully compatible with IEEE 802.3 and IEEE 802.3u standards. They have MDI/MDIX auto detection feature and automatically find and set the fastest connection speed and mode. "Store and forward" mechanism allows to verify the received data using checksum function.

Needs and requirements of Internet users are constantly increasing. Telecommunications operators, wishing to satisfy the needs of customers, must provide them with a high-speed Internet and other broadband services, including TV and video transmission. Only fiber-optic technology brought directly to the end user's home or site (FTTH - Fiber To The Home) is able to provide all the services simultaneously and practically without any limits.
Media converters are widely used for the transmission of Ethernet signals over long distances and in areas exposed to harsh weather conditions. Optical fibers provide full electrical insulation and resistance to electromagnetic interference. Media converters are primarily used to connect building LANs (e.g. of scattered buildings of one corporation).
Ethernet Media Converter ULTIMODE M-207M<br />(one single-mode fiber up to 20 km)Switch TP-Link TL-SF1008D (8 ports)
Example application of ULTIMODE media converters
List of parameters of ULTIMODE media converter series:
Supported standards:IEEE 802.3, IEEE 802.3u
Transmission speed:10/100 Mbps10/100/1000 Mbps
Optical connectors:2xSCSC
Range [km]: 240204020
Tx/Rx [nm]:
1310/13101310/1550, 1550/1310
Ethernet port:RJ-45
Power:DC 5V/2A
NUUO DVRs - a new standard of video surveillance. NVR (Network Video Recorder) NUUO is innovative Plug &Play device for full management of IP CCTV system. The main functions include live monitoring, recording of video streams, playback of the archives. This flexible NVR platform allows multi-server multi-client operation. NUUO NV-4080 K4108 allows to record video streams from megapixel (up to 5 Mpix) and standard-resolution cameras, with frame rates up to 25 fps. Due to Linux OS, it ensures stable operation and resistance to computer viruses.
NUUO NVRs are used in all kinds of maintenance-free systems. In this kind of small- and medium-size systems the NVR can be connected to any node of IP network and provide service for a number of customers (clients) with hierarchical access rights. The access to the system is needed only in certain situations (e.g. alarms). Application of NVRs also means a significant reduction in the costs of the system (no need for a computer with high computing power). Such systems are suitable for surveillance of offices, factories, warehouses, stores, businesses, various buildings etc.
The system is operated only remotely (via IP network). There is no need to create or define a monitoring center, because its functions can be performed from any point of the network. The connection is via Internet Explorer or client software. The former solution is convenient for its simplicity (no need to install additional applications), while the latter makes it possible to work on several servers at once.
Network Video Recorder (NVR)<br />Storage and management solution for IP CCTV system
The structure of IP CCTV system based on NUUO NVR
"ULTI-monitoring" in cities. Building extensive monitoring system, such as video surveillance system in a city, one should use proven solutions and systems approach. Many installers have bad experiences with the devices which independently operate very well, but have problems with communicating each other. Therefore, only advanced and tested solutions can ensure proper operation of the system.
Elements of CCTV systems verified in urban and other large installations:
The main features of a modern monitoring system are:
  • megapixel resolution allowing to precisely monitor the scene
  • MPEG4 / H.264 compression ensuring optimum efficiency of video data transmission and storage;
  • highest quality lenses that do not limit capabilities of the cameras (especially in the case of megapixel devices);
  • reliable cable, fiber optic, or wireless transmission;
  • recording system supporting resolutions of the employed cameras;
  • DVRs in local systems capable of integration with the main system.
Software Package: ULTISYSTEM (32 channels)IP Camera ULTICAM DS-852MF-E (2.0 Mpix)Wireless Access Point: ULTIAIR 423KCH.264 IP Camera: ULTICAM DS-2CD892PFWireless Access Point: ULTIAIR 323KCNetwork DVR: ULTIMAX-204 (H.264, 4 channels)Ethernet Media Converter ULTIMODE M-207M<br />(one single-mode fiber up to 20 km)Ethernet Media Converter ULTIMODE M-207M<br />(one single-mode fiber up to 20 km)
"ULTI-monitoring" - a comprehensive video surveillance system
New video clips in ACTi library. We invite everyone to the Library of Megapixel ACTi Video Clips, with new megapixel materials: the K1315 camera image from an office, recorded at night, entrance to a parking lot monitored with K1511 camera, and view of a park through the K1514 camera.
TRANS-DATA - professional telecommunications antennas. TRANS-DATA is a brand of high quality antennas for wireless reception and transmission of digital data in 806-960 MHz and 1710-2500 MHz bands.
Thanks to high quality materials and very good performance, the antennas are characterized reliable and stable parameters. TRANS-DATA antennas significantly improve signal strength and increase the coverage area.
Distinguishing features of TRANS-DATA antennas:
  • High quality products,
  • Stable parameters,
  • Robust designs,
  • Strong and stable mounting systems,
  • Good value for money,
  • Careful quality control of raw materials, components, and final products.
  • indoor use, omnidirectional characteristic,
  • broadband device: 806-960MHz and 1710-2500MHz (GSM/DCS/UMTS),
  • 3 dBi gain,
  • VSWR <1.5,
  • compact size,
  • easy fixing to plasterboard or other suspended ceilings.
  • indoor use, omnidirectional characteristic,
  • broadband device: 806-960MHz and 1710-2500MHz (GSM/DCS/UMTS),
  • 3 dBi gain,
  • VSWR <1.5,
  • compact size,
  • fixing to ceiling with the use of expansion bolt.
  • outdoor/indoor use, directional characteristic,
  • broadband device: 806-960MHz and 1710-2500MHz (GSM/DCS/UMTS),
  • 7.5 dBi (806-960MHz) and 10 dBi (1710-2500MHz) gain,
  • VSWR <1.5,
  • fixing to wall
  • outdoor use, directional characteristic (Yagi),
  • broadband device: 806-960MHz and 1710-2500MHz (GSM/DCS/UMTS),
  • 8.2 dBi (806-960MHz) and 9.5 dBi (1710-2500MHz) gain,
  • VSWR <1.5,
  • fixing with U-bolts
Economic router integrated with Access Point - an ideal solution for home users. TP-LINK TL-WR340G 54 Mbps N2952 is a wireless router, integrating router, firewall, and access point. It has been designed to provide internet connectivity to small and medium businesses, as well as to private users in apartments and one-family homes.
TP-Link TL-WR340G enables the user to build wireless network quickly and easily and to share Internet connection among a number of computers - ensuring additional protection due to built-in firewall.

Wireless xDSL Router: TP-Link TL-WR340G<br />(built-in 4-port switch and AP) Wireless CardBus Adapter: TP-Link TL-WN510G (2.4GHz 54Mbps, eXtended Range)Wireless USB Adapter: TP-Link TL-WN321G (2.4GHz 54Mbps)
TL-WR340G integrates access point, broadband router (for xDSL or cable modem), and 4-port FastEthernet switch. It is an ideal and economical solution for home users.
Main features of TL-WR340G
  • MAC address cloning
  • firewall
  • Internet access filtering
  • static / dynamic routing
  • AP in 802.11g/b standards (up to 54 Mbps)
  • router
  • built-in 4-port switch
TL-WR340G ensures advanced access control, NAT, and its DHCP server supports static assignment of IP addresses. It is possible to use virtual servers, DMZ, remote managing and logging.

Recommended articles from our Library:

ULTISYSTEM - advanced surveillance software. The ULTISYSTEM software has functionality of professional NVR (Network Video Recorder) that manages IP CCTV systems based on transmission of surveillance data in Ethernet network. The software can fully integrate a whole set of IP CCTV devices (IP cameras, video servers, DVRs). Application of video servers and ULTIMAX DVRs allows to utilize any analog cameras. The distinguishing feature of this software is support for megapixel IP cameras...

Instructions on how to properly protect connections
with self-amalgamating tape.
Self-amalgamating SCAPA 2501 tape is based on PIB (Polyisobutylene) rubber. It is a versatile material for waterproofing, corrosion protection, jointing and repair of cables - used indoors and outdoors. Product properties and correct application ensure waterproof connections (for fresh and sea water) in a wide range of temperatures...

ULTIAIR - efficient and secure wireless data transmission. ULTIAIR is a family of professional Access Points, designed for efficient long-term outdoor operation. Integration of the transceiver and antenna into one weather-resistant housing enables the installer to perform the job quickly, without additional operations...

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