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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 15/2009 (April 14, 2009)
Home multimedia center. Home IP networks are increasingly equipped with network drives. The Network Attached Storage (NAS) is used to create data libraries as well as backup storage.
More and more space in the store is taken by multimedia files - photos, movies, music - so it is logical to connect the network to the stereo, HD television, home theater projector.
There is available home equipment with LAN ports, among other things televisions that can cooperate with other devices compliant with DLNA (The Digital Living Network Alliance) certificate. The standard developed by this international body is being implemented in televisions, digital video recorders (DVRs), cellular phones, NAS drives, stereos, home theaters, PCs, laptops, netbooks, palmtops, network printers.
Connecting the TV set to the home network, the user gets access to the media in the home archive or stored e.g. on his/her mobile phone. For example, selected photos from the mobile phone can be printed during watching them on TV.
If the devices use different standards, it may cause problems. On the Internet the users can find lists of compatible software, operating systems and types of multimedia, as well as appropriate transcoders.
To avoid such problems, simpler solutions are based on hard drives equipped with USB ports (for recording the files) and HDMI, RCA or optical outputs for connection to a home theater.

An integrated concept of home multimedia system was shown at CeBIT 2009 by NETGEAR Inc.
The solution combines in one network with Internet access a number of devices:
  • desktop and mobile computers with wired and wireless cards,
  • NAS drives,
  • wireless USB print server,
  • WiFi SKYPE phones,
  • powerline Ethernet adapters,
  • multimedia players (digital entertainers).
The core of the home system is one or more multimedia players. They provide access to the multimedia from the archive, home LAN or the Internet. The signals from the players are available in AV, Component Video, Cinch, S/PDIF (coaxial/optical), S-Video, HDMI connectors. The "digital entertainers" are equipped with both wired and wireless Ethernet interfaces.
For transmitting HD video, the company recommends wired links. The reason is that wireless networks (aside from IEEE802.11n draft 2.0) are not suitable for such transmissions. Typical HD movie requires effective (and stable) throughput at a level of about 20 Mbps (it is close to the practical limits of the devices using IEEE802.11a or EEE802.11g standards).


Interactive presentation of the Netgear concept of multimedia home
The nicest hostesses. Their work is aimed at promoting companies, fair stands and products. They are a nice accent in the space filled with goods. The women should be attractive and catch the eyes of the visitors.
In our reports from various trade fairs and exhibitions we have put many pictures with hostesses. Who is the nicest one?

Welcome to a picture gallery

The nicest hostesses
The nicest hostesses
The nicest hostesses
What can deteriorate community antenna installation? The quality of SMATV/MATV system strongly depends on transmission parameters of distribution network consisting of cables and connectors.
One of the basic parameters that characterizes quality of transmission line is return loss, a measure of impedance matching. It shows the proportion of the reflected and transmitted energy, sent from the source to the receiver via the cable and connector. This parameter is given in decibels (dB) and should be as high as possible. For example, return loss of 20 dB means that the amplitude of the reflected back signal is ten times lower than the amplitude of the input signal.
High return loss is obtainable when using good quality cables and connectors, and ensuring professional installation of the stuff.
Impedance matching can be deteriorated by the installer who changes geometry of the cable, e.g. stepping on the cable, pulling it hard through a narrow hole, stuffing and bending it in installation boxes, bending it over too small radius or fixing it to the wall with too tight cable clips.
Connectors have also very significant impact on the quality of the entire path. Their poor quality can diminish the effects of using even highest quality cables. The connectors used outside buildings should have adequate protection against water. This is of fundamental importance, since a little bit of water will result in an increase in SWR (Standing Wave Ratio) up to several dozen percent, so the energy will be converted into heat.
Another important factor is the way of assembling the connectors, without damaging structure of the cable during crimping operations.

To correctly install the wiring, one should remember to:
  • use highest quality cables (TRISET),
  • install them carefully - without stepping, jerking, hitting, bending more than the minimum allowed radius.
Using best cables it is sensible to employ quality compression connectors, e.g. E80340, that ensure:
  • waterproof termination of the cable,
  • resistance to corrosion - made of non-ferrous metals and highest-quality dielectric,
  • very low loss in the whole operating band,
  • perfect matching to the transmission line within the whole operating band,
  • simple and quick assembly: longitudinal compression.
Tvrdosin - the sign of a new trend in video surveillance. In the evening, a woman returns home along a sidewalk in the housing area. She is followed by two young men with hoods pulled over their heads. They look around, run up to the woman and snatch the purse, then join three other people, also identified as offenders... The perpetrators were caught several days after running a new video surveillance system in Tvrdosin.
Images from 2.0 Mpx ULTICAM K1441 cameras in Tvrdosin
(click on to enlarge)
Tvrdosin is a town with over 10,000 inhabitants, located 12 km from the Polish border (on the Chyzne - Ruzomberk route). The region is full of tourist attractions - Meander Park Thermal in Oravice (thermal watering place), Orava reservoir (large artificial lake), and ski areas. The city authorities decided to build video surveillance system to prevent acts of vandalism and other offenses. The system should be cost-effective, also in long-term perspective (low operational costs of monitoring center).
Traditional monitoring based on PTZ cameras can be effective only when is operated around the clock by a qualified staff. In the case of the small town the costs would be unacceptable.
DIPOL Slovakia proposed to build a system based on fixed megapixel cameras. It is the sign of a new era in video monitoring - use of a combination of megapixel cameras with wide-angle lenses instead of PTZ devices.
Implementation:
The system employs eight 2.0 Mpix IP cameras ULTICAM DS-852MF-E K1441. Three of these cameras have been installed on the walls of the town hall, the rest are deployed in the housing area called Medvedzie. This district is 680 m away from the monitoring center. The video is transmitted wirelessly with Access Point integrated with antenna - ULTIAIR. Each of the five video streams is sent at data rate of 4 Mbps, which is sufficient for high quality of the images (1600 x 1200 @ 12.5 fps). The monitoring center is located in the town hall. The system is managed (monitoring and recording) by ULTISYSTEM software. High-resolution images, both live and played back from the archive, can be digitally enlarged many times enabling identification of people who do not respect the law.

Full description of IP CCTV system in Tvrdosin
Deployment of cameras in the housing area in Tvrdosin
Multiple images at the "SPOT" output of DVR. Most DVRs available on the market have two composite video monitor outputs (CVBS).
- The primary output is usually labeled as "MAIN" - the attached monitor can display many images in screen division or any single image in full screen mode. This output also provides OSD menu.
- The secondary output is often labeled as "SPOT" - the attached auxiliary monitor can usually display the full image from an "alarm" camera or sequence of full images from all cameras.
ULTIMAX DVRs are practically the only devices on the market which allow to display on the auxiliary monitor any combination of multiple images. The administrator can define the displayed cameras and their layout.
Possibility of displaying a number of channels on second screen is a very useful function, often required by customers. It allows to create another surveillance post, without a need of using additional components like multiplexers, video amplifiers etc.
As mentioned, the administrator can select the set of the displayed images, limiting access to the system for some users. As an example, the surveillance staff can have access only to nine outdoor cameras, whereas the owner can watch images from all channels.
Notice! Split screen images at SPOT output are available in ULTIMAX DVRs of 500 and 700 series.
Configuration of additional output (SPOT) in ULTIMAX- 5xx and ULTIMAX-7xx DVRs
RTSP in IP CCTV devices. RTSP (Real Time Streaming Protocol) is a network control protocol for use in entertainment and communications systems to control streaming media servers.
IP devices equipped with RTSP protocol allow the user to view the images (or/and listen to the sound) in real time with any multimedia player supporting this protocol (e.g. VLC, QuckTime Player, RealPlayer) and/or to perform "restreaming" in order to post the material directly on a website (thanks to receiving RTSP stream via Media Server).
The standard communication port is 554. The devices allow to change the number of the port, giving users the opportunity to export outside LAN signals from a greater number of cameras.

DIPOL offers many types of cameras with RTSP protocol:
ULTICAM online camera - Wawel in Krakow
Example of restreaming with the use of RTSP protocol
supported by megapixel camera ULTICAM DS-852MF-E
- view of Wawel in Krakow
Recording features of NUUO NVR mini. Network Video Recorders NUUO K4104 and K4108 enable full management of IP CCTV systems.
Despite small size, they allow full-speed (25 fps) monitoring and recording of cameras with standard resolution (D1: 720 x 576), as well as synchronized recording of sound channels. The NVRs also allow to record video streams from megapixel cameras (up to 5 Mpix).
The NVRs can operate in three modes: continuous recording, schedule recording, no recording.
Separately for each channel the user can set the days of the week and time periods of recording, both in the case of fixed and triggered (by events) mode. For example, the first channel may be recorded from Monday to Friday, from 8.00 to 16.00, but on Saturdays from 9:00 to 13:00, etc. In other times, the recording will be triggered by motion detection or activation of an alarm input. A movement or state of emergency occurring in a single channel can trigger recording of other channels. These features work only with devices equipped with motion detection function and alarm inputs.
Network Video Recorder: NUUO NV-2040
NVR NUUO NV-2040 K4104
Recording schedule window in NUUO NVR
Remote monitoring of images from ULTIMAX DVRs via the Internet. In residential or small business applications the DVR is one of the devices connected to the local network. If the Internet is provided via popular ADSL line, the network can be easily built using router with integrated ADSL modem - TP-LINK TD-W8910G N2901.
Effective connection with the DVR requires appropriate configuration of the router, in particular - port forwarding.

For this purpose the user should:
  • log on the router (how to do it - in DIPOL's library - Configuration of ADSL routers),
  • choose Advanced Setup >> NAT >> Virtual Servers,
  • select Custom Server option and enter the name of the redirection (below: "ULTIMAX"),
  • enter in the Server IP Address field the internal IP address of the device to be redirected,
  • enter desired ports or range in the External Port Start/End fields, choose the protocol, enter Internal Ports (for ULTIMAX - ports 80 and 8000),
  • click on Save/Apply.
Configuration of TP-LINK TD-W8910G N2901.
Selection of the Virtual Servers item
NAT - Virtual Servers window
(parameters suitable for ULTIMAX DVR)
Since then, the user entering in the browser the appropriate address:
http://user.address.ip:88 or http://user.domain.name:88 will get the DVR welcome menu allowing to log on and view the images.
Efficient wireless networks based on ULTIAIR devices - "point-to-multipoint" topology (part 2). The main advantage of wireless backbone based on "point-to-multipoint" topology is lower cost of the system - comparing it with the "point-to-point" scheme described in the previous issue of the Newsletter. To cover the whole area (360 degrees), one requires only a single omnidirectional antenna or set of sector antennas.
This combination has, however, a significant disadvantage - it limits the maximum transfer to 23 Mbps shared among all clients. This is because the transmission to all client stations is performed using the same channel, so the available bandwidth of the channel has to be divided.
Another drawback is a low resistance to interference from other wireless networks, due to the wide angle of operation of the base station antenna/s.
ULTIAIRWireless Access Point: ULTIAIR 319KCWireless Access Point: ULTIAIR 319KCWireless Access Point: ULTIAIR 319KCWireless Access Point: ULTIAIR 417SB
Example wireless network based on point-to-multipoint topology

In the example above, ULTIAIR 417SB N2330 operates as the base station (in access point mode). Three ULTIAIR 319KC N2310 devices work as client stations (in client mode). ULTIAIR 417SB N2330 is integrated with antenna featuring a 90-degree half-power beam. It allows for communication with the clients deployed within a quite wide angle.
A short summary:
  • The optimum solution for small wireless networks without high bandwidth requirements is point-to-multipoint topology.
  • If the network grows or the bandwidth requirements are high, one should choose point-to-point concept, which allows to obtain much faster data transfers, better coverage of the whole area, longer range, greater resistance to interference.
We have written about:

CCTV cables. The cables used in CCTV systems often have to be quite long, both in the case of video and power transmission. There is no big problem with long-distance video transmission. Our tests show that CAMSET 50 75-0.59/3.7 M6050 cable can transmit video up to 300-400 meters without perceptible loss of quality. ... Using Ohm's law - a camera of 245 mA consumption can be powered via CAMSET 50 M6050 cable over a distance of about 60 m. Using CAMSET 100 M6100 the distance doubles to about 120 m...
- archive DWR of Sept. 15, 2008

How to share a standard USB printer for all WLAN users? The wireless print server TP-LINK TL-WPS510U N3310 is ideal for use in offices and homes, eliminating the need of connecting cables from mobile computers to the printer. It also allows to print documents from many computers on one printer...
- archive DWR of Feb. 9, 2009

Prevention and diagnostics of problems with LAN cabling - Multifunctional Cable Tester N7058. NetWork Cable Tester N7058 with LCD display enables the user to verify proper installation of Ethernet cabling (CAT 5e, 6e) and telephone lines. The tester allows to check...
- archive DWR of March 2, 2009

Index of published issues
Earth Hour 2009 - lights on Wawel, Krakow - images from 2.0 Mpix camera ULTICAM K1441
 
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