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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 9/2008 (March 3, 2008)
HD DVD - the end of competition. On February 19, 2008, Toshiba officially announced the discontinuation of HD DVD format. It means end of the "second technological war" for video recording standard. Before the latest campaign for blue-laser format (HD DVD vs. Blu-ray), there was the clash between videotape formats (VHS vs. Betamax).
Probably the final blow was dealt by Warner Bros. - it was the information about decision of releasing its high-definition DVD titles exclusively in Blu-ray disc format - beginning since June this year. After that Wal-Mart Stores decided to withdraw HD DVD players. It did not help at all that Xbox 360 consoles equipped with HD DVD players sold well in the end of last year (ca 100,000 pieces). Toshiba informed about a million HD DVD players sold by January of 2008. There were released 386 HD DVD films in the U.S., and 214 in Japan.

Paradoxically, the defeat of Toshiba, Nec, and Microsoft, will be a strong and invigorating impulse for quick development of the field. The potential customers will not be in a dilemma over which to choose or when to buy (waiting for a market resolution). It is also a chance for related businesses - film, TV, and electronics industries (higher demand for large-screen high-definition televisions and HDTV productions).
There is approaching the period when majority of people in the world will think about changing their TV/video equipment. Already this year the producers and distributors should begin to share the prosperity.
BDA stand (Blu-ray Disc Association) at IFA in Berlin. The number and potential of producers of the discs are sufficient for mass-market production.
Telecommunications in Israel. Telecommunications is one of the most important industries in this small country with 7.7 million population. Its technological level can be measured by the percentage of homes using broadband access to the Internet - ca. 70%, securing the fourth position in the world - after South Korea, Hong Kong and Iceland.
Mobile telephony is also included in the top rankings - already in 2006 there were more mobile phones than the number of inhabitants (by 7%).
97% of the residents can potentially use cable TV (52% of households subscribe it).
Israel belongs to the small group of countries having own satellites. The first satellite has been successfully launched on the orbit in 1996, and together with the second one - AMOS-2, is mainly used for direct TV transmissions. About 22% households subscribe digital satellite platform "Yes" from AMOS.
Other satellites, Gurwin-II TechSAT and EROS, are used for communication, cartography, and other research purposes.
Great potential of high-tech industries in Israel has attracted international corporations - the first overseas R&D divisions of such giants like IBM, Motorola, Cisco, or Deutsche Telekom were opened just in this country.
Among the companies listed on the NASDAQ stock market, Israeli firms are the second most numerous group (after Americans). They include so well known firms like Alvarion, Gilat Satellite Networks, Radware, RAD Data, Tadiran, Teledata, Telrad, VocalTec, Verint.

Telecommunications in Israel - a photo report.
The roofs of Jerusalem - full of satellite dishes
Satellite and terrestrial TV in one cable. There can be built one-cable installation distributing satellite signals from two full-band LNBs and set of terrestrial TV antennas. The installation is based on combining signals from terrestrial TV diplexer and sat switch. Choice of the LNB is done with Golden Interstar switch (R852506). The terminal outlet (R694100) is equipped with filters that separate the satellite and terrestrial signals.
VHF TV Antenna: DIPOL 7/6-12 (7-element)Anodized FM Antenna: Dipol 1RUZ A (omnidirectional)UHF TV antenna: DIPOL 19/21-69 DIGITALAntenna Triplexer - ZA 4MFull Band LNB: Golden Interstar GI-201 (0.3 dB) DiSEqC 2.0 / Tone Burst Switch: Golden Interstar GI 211 (2/1)TV/Sat Combiner (Diplexer) DC-009 TerraTV/SAT Wall Plate: Signal R-TV-SAT (terminal)
Diagram of installation allowing one-cable distribution of satellite and terrestrial broadcasts
Reception of DVB-T. Properly designed and implemented antenna system for receiving analog TV will also be suitable for reception and distribution of DVB-T (or DTT - digital terrestrial television). All offered antenna amplifiers correctly convey digital signals. When the DVB-T channels are transmitted from another location, there will be needed additional antenna, and, possibly, change of the amplifier for one with adequate number of UHF inputs (e.g. AM-417 R903717).
To receive DVB-T signals the user needs to employ an appropriate DVB-T receiver (e.g. in Poland - MPEG-4, in Czech republic and Hungary - MPEG-2). Some LCD televisions are equipped with built-in tuners.
Taking into consideration gradual process of changing older TV sets, and the offer of new programs contained in digital multiplexes, it is recommended in building installations to convert such programs into analog form available for every user. For this purpose there is needed DVB-T receiver, RF modulator, and channel amplifier.

In Poland DVB-T programs are available in several locations, e.g. in the central part of Krakow (ch.37, 5watt, 16QAM modulation - 8 programs).
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 DIGITALBroadband RF Amplifier: Alcad CA-2154-way TV / FM Splitter - Signal R-4
For individual reception of digital TV every television has to be equipped with DVB-T receiver
H.264 - 3rd Generation DVRs. The kind of video compression is one of the key factors influencing the overall quality of recorded video. M-JPEG and M-JPEG 2000 systems, where each video frame is separately compressed as a JPEG image, are usually used for low frame rates, offering single frames of high quality (e.g. from megapixel cameras). Recording of dynamic scenes requires efficient difference algorithms that are implemented in MPEG wavelet compression systems.

The diagrams below present rough comparison of some parameters (for similar image quality) when using different versions of MPEG compression (implemented in different DVRs). It is clear that H.264 algorithms, used in 3rd generation DVRs, ensure the best results - the lowest bandwidth and disc space requirements, the shortest download time. The parameters are about 30% better than in the case of "normal" MPEG-4 compression.
H.264 is currently the only compression that allows to build 16-channel DVRs capable of recording D1 video (PAL 704x576) at frame rate 25 fps, as well as providing effective network transmission of live and recorded images.
Bandwidth requirements
Disc space requirements
Download time
Comparison of different versions of MPEG compression
IP CCTV - new concept of monitoring center. City monitoring system can be a powerful source of information, not only for the police but also for other city services, such as fire brigade, street services etc. For this purpose the best solution is to base the system on a central server. It allows to create several monitoring posts in different locations, without risk of "overloading" the cameras.
Flawless operation is possible due to server - client architecture. Additional posts are using sever resources, not influencing the cameras..
The maximum number of users depends on computing power of the server, needed for re-compression of video streams for individual clients.
This concept has been implemented in monitoring system in Myslenice. The system has been based on Netstation K3232 managing software and ACTi K1215 cameras.

Video surveillance system in Myslenice
Video surveillance system in Myslenice based on central server
Wireless backbone. For this purpose there is often used unlicensed 5 GHz band and set of wireless devices compliant with IEEE802.11a standard.
The example of powerful wireless equipment is the family of Aphelion devices, with the following models: 500AG N2411 (1 transceiver), 600AG N2412 (2 transceivers), and 3300AG N2413 (3 transceivers).
The devices work in unlicensed 2.4 and 5 GHz bands, ensuring freedom of action. They may be used for creating independent access networks for any client devices.

Main features of Aphelion family that make it very competitive on the wireless market:
  • Designed for wireless backbones with advanced QoS mechanisms.
  • Optimized for efficient Internet access, IP CCTV monitoring, VoIP telephony.
  • Certified (IP67) outdoor housing ensuring full protection against adverse environmental conditions, including those of industrial environment.
  • Possibility of creating MESH networks with Hot-Spot and Hot-Zone functions, efficient trunks with intelligent load balancing between two antennas, and backup links (real transfers of 60 Mbps, max.162 Mbps). TRUNK connections allow better efficiency due to aggregation of a number of physical connections into one logical link, without a need of additional equipment like load balancers.
  • Management functions are performed in text mode via SSH console (with data encryption).
A proposal of integrated wireless infrastructure for towns and cities, based on Aphelion devices.
Wireless access point Aphelion 500AG N2411
Wireless access point Aphelion 600AG N2412 (2 transceivers)
Wireless access point Aphelion 3300AG N2413 (3 transceivers)
Aphelion family

Name

Wireless access point Aphelion 500AG

Wireless access point Aphelion 600AG

Wireless access point Aphelion 33000AG

Code

N2411

N2412

N2413

Standards

IEEE 802.11a/b/g,

IEEE 802.3/u/af

Modes of work

Access Point,

AP Client,

Bridge,

Router

Memory

64 MB (RAM),
8 MB (flash)

64 MB (RAM),
16 MB (flash)

64 MB (RAM),
32 MB (flash)

Frequency range

2400 MHz ÷ 2483 MHz,

5150 MHz ÷ 5350 MHz,

5470 MHz ÷ 5725 MHz

Max. RF power

18 dBm

Antenna connector

 N(F)

2x N(F)

3x N(F)

QoS

802.11e WiFi QoS

 WLAN security features

SSID Disable,

64/128/152 bit WEP,

WPA,

WPA2,

802.1x,

Mac Address Filtering

Bandwidth management

yes

Housing

outdoor (IP67)

Power

AC/DC PoE adapter (in: 100 ...240 VAC)
out: 48 V DC / 0.8 A

We have written about:

Antenna system measurements. Knowledge of signal parameters, among others: differences in levels of useful signals, signal levels in subscriber outlets, BER, level of noise and interferences allows to prepare optimal design and verify actual results...
- archive DWR of Nov. 19, 2007

Home and business Wi-Fi networks - applications of TP-Link family TP-Link in one of the leading producers of network devices for home and business applications. The devices are reliable, easy to configure and offer modern design...
- DIPOL's Library

Monitoring of dispersed locations - how to lower cabling costs. Video transmitters/transformers allow to use UTP/FTP cables for video transmission, which lowers the cost of cabling by 50%...
- archive DWR of Sept. 10, 2007

Index of published issues.
IP CCTV - the Systems of Today and Tomorrow - DIPOL at Intertelecom trade fair in Lodz, Poland: April 8 - 10, 2008
DIPOL at Intertelecom 2008 - see our virtual stand
 
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