DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN

No. 24/2013 (June 10, 2013)

When will we use self-driving cars?

Intel International Science and Engineering Fair is the largest pre-college scientific research event in the world, organized for young people between 12 and 18 years of age. This fair has tradition dated back from 1959, and has been sponsored by the Intel Corporation since 1997. This year's edition was held in May in Phoenix, Arizona. The winner of the grand prize has been Ionut Budisteanu from Romania, who developed a prototype of an autonomous car. The scholarship (USD 75,000) will allow him to continue studies and the further development of the project.
Self-driving cars are nothing new, since 2010 Google has been working on its own project under the name "Google Car", but unlike the student from Romania the American giant does not have to think about reducing the budget. In the Google's project a 3D radar alone cost about USD 75,000, while the whole system built by Ionut Budisteanu was priced at USD 4,000.
The solution of the young inventor is based on image analysis from cameras mounted on the car, which identifies curbs, lanes, passers-by, and other objects on the road, even a ball. Additionally, the system is supported by the data from a low-resolution 3D radar identifying large objects, such as other cars, houses and trees. All the information is collected and processed in real time by a set of computers that send the results of their calculations to the main unit, deciding the trajectory of the car.
So far, Budisteanu made ​​about 50 trials of the system. In three cases, it failed to recognize a man at a distance of 20-30 meters. According to the designer, the problem should be eliminated by application of a higher-resolution radar, but still much cheaper than that used by Google.
The idea behind self-driving cars is to prevent errors that are often made by drivers because of fatigue or distraction. Ultimately, the cars are to eliminate humans from the driver's seat and replace them with "infallible machines" based on sets of sensors and computers running sophisticated software. It would be especially useful in the case of taxis, vans and trucks, eliminating the problems of working time limits of the drivers. And there are car owners who would rather be passengers ...

Optical fiber fault location.

Tests of optical links require a bit more advanced tools than in the case of copper cabling. When the devices on both sides of a link work properly, but the connection fails, it must be a fault of the transmission medium.
How to check the fiber? There are three methods:
The first of them is to use an optical time-domain reflectometer. Such an optoelectronic instrument is able to measure practically all parameters of the fiber and precisely indicate the distance to the fault. It is enough to get there, cut the fiber and splice it. However, reflectometers are expensive and usually not available for field installers...
The second, less accurate way is to measure fiber attenuation with an optical power meter and a stable light source - it may confirm a failure, but will not indicate the location of the problem.
Visual Fault Locator: VFL650-5
Visual Fault Locator: VFL650-5
Working with visual fault locator. The picture shows "leakage" of light from the cable -
the damage is likely the result of improper handling of the fiber when connecting devices.
The third method is based on the application of a visual fault locator. It provides very good results when the technician has physical access to the cable along its entire length. It is easy to locate a fault on the basis of a "leakage" of light. The applicability of this method depends on the thickness of the cable. In the case of fibers with 0.9 mm buffer, the damages are typically visible even through layers of 3 mm thickness. The VFL650-5 L5934 locator is designed to test single-mode and multimode fiber-optic cables. The output power is sufficient to check even 5 km long links.
In addition to optical path testing, the visual fault locator is an ideal tool for anyone mounting KeyQuick and Ultimode connectors and mechanical splices. After connecting the fault locator to a mechanical splice or connector with transparent body, the installer can control the quality of the connection made and estimate its transmission parameters.

Satellite and terrestrial TV in a hotel.

The owner of the hotel decided to install SMATV system distributing 8 satellite channels in SD format and 2 in HD format, as well as DVB-T channels from three digital multiplexes. The signals should be distributed to about 50 modern televisions, without a need to use satellite receivers. Due to the functionality and price, the choice fell on TERRA MMH-3000 headend.
The headend distributing TV channels from four satellite transponders, in the form of DVB-T multiplexes
The base unit of the MMH3000 headend (UC-380 R81700) houses up to eight Terra modules. There were selected the following modules: 8PSK+QPSK CI receiver / DVB-T@COFDM modulator TDX-311C R81711C (with CI slot), 3x DVB-S/S2 receiver RDC-311 R817102 (also with CI slot), and DVB-T modulator TRX-360 R81709. The TDX-311C R81711C receiver / DVB-T (COFDM) modulator (transmodulator) is used to receive encrypted or FTA channels. One device is sufficient for a whole transponder which is converted into a DVB-T multiplex (7-8 channels in standard definition or 2-3 channels in high definition). The channels that are located on other transponders are received by the RDC-311 R817102 receivers and converted into DVB-T standard by the TRX-360 R81709 modulator.
The set of TERRA at420 R82510 channel amplifiers (or one four-channel amplifier Terra at440 R82511) ensures selective amplification of terrestrial DVB-T multiplexes, which are combined with the DVB-T (converted) signals from the headend.

IR illuminators - invisible IR lighting.

Infrared illuminators are used in CCTV systems operating in places/areas with insufficient visible lighting, which typically occurs in the evening and night. The basic parameters of them are electrical and optical power, wavelength of the infrared light, directional characteristics.
Infrared lighting is generated by IR illuminators operating in the near infrared range, i.e. 700-1000 nm. With increasing the wavelength, the light of a glowing lamp or IR LED is less visible to the human eye, e.g. 750 nm - visible glowing, 830 nm - almost invisible glowing, 940 nm - completely invisible to the human eye.

The Exview image sensor with at least doubled sensitivity in IR range
is very effective in cooperation with IR illuminators
IR illuminators Redbeam IRN60 M1653 (range up to 60 m) and IRN40 M1649 (range up to 40 m) operate in far infrared range - they generate radiation at the wavelength of 940 nm, invisible to the human eye. For the efficient use of IR illuminator working in the 940 nm range it is necessary to employ a camera that is sensitive to radiation at this wavelength, for example from a family based on Sony Exview sensors. As shown in the graph, the sensitivity of the sensors in IR range is significantly higher than that of common sensors, especially around 950 nm. The cameras which also operate in daylight should be equipped with mechanically switching IR filters (ICR).

Video surveillance of sites used seasonally.

The protection of buildings and other facilities used only at certain times of the year (summer houses, ski slopes, outdoor pools etc.) is often more troublesome than in the case of homes and offices. Because of their remote location from city centers, it is not always possible to use standard Internet connections.
The solution to this problem is access to the security cameras and DVR via a 3G modem router. DVRs do not support UMTS/HSPA modems with USB interfaces, so one needs a suitable router supporting 3G modems, e.g. TP-LINK N2957 TL-MR3420.
3G Wireless Router: TP-LINK TL-MR3420 (802.11n, UMTS/HSPA)CCTV Network DVR: HIKVISION DS-7208HVI-SV (8ch-WD1-HDMI)Vandal-proof Dome Camera: SN-FXP59/50UDR (650 TVL, Sony Effio-P, ICR, 0.03 lx, 2.8-10mm, IR up to 20m)
Cooperation of M72108 DVR with the N2957 router and a 3G modem
For the proper operation of the DVR it is necessary to have sufficient bandwidth of the 3G connection (at least 200 kbps per one video channel - auxiliary stream) and an external IP address. The M72108 DVR supports DDNS services that allow users to facilitate the connection to the Internet. The DVR can be configured to transmit only alarm events. The router with 3G modem can also be used as WiFi AP for the access to the Internet throughout the whole facility.

How to solve compatibility problems between a TP-LINK 3G router and some 3G modems?

For a wide compatibility, TP-LINK company tests its routers with all popular 3G modems and continually updates the firmware and the list of compatible modems. Despite these efforts, there may be some items that present compatibility problems.
To solve such a problem, the user can perform the following actions:
  • Way 1. Due to the mentioned constant firmware updating, the user should first try to find the 3G modem on the current list of compatible devices. If the modem is on the list but the status window of the router shows information about an unrecognized device (Unknown Modem), the user should update the router firmware. The latest firmware is available at tp-link.com. After downloading, it can be installed by selecting System tools->Firmware Upgrade.
  • Way 2. If a 3G modem has not yet been included into the latest firmware update, there is a chance that the suitable software can be found in 3G Modem Bin File Center. The suitable binary file should be downloaded onto a computer's hard drive and then loaded to the 3G router.
Popular TP-LINK routers supporting 3G modems:
3G Wireless Router: TP-LINK TL-MR3420 (802.11n, UMTS/HSPA)
3G Wireless Router: TP-LINK TL-MR3220 (802.11n, 150Mb/s, UMTS/HSPA)
TL-MR3420 802.11n 300Mbps
TL-MR3220 802.11n 150Mbps
3G Wireless Router: TP-LINK TL-MR3020 (802.11n, 150Mbps, UMTS/HSPA)
Mobile 3G Router: TP-LINK TL-MR3040
TL-MR3020 802.11n 150Mbps
Mobile 3G TP-LINK router
New products offered by DIPOL:
Vandal Proof Camera: v-cam 520 (day/night, D-WDR, 650 TVL, Sony Effio-E, 2.8-12mm AI, OSD, 0.01 lx)
DVB-T Receiver: Opticum HD N3
Visual Fault Locator: VFL650-5
Vandal Proof Camera: v-cam 520
(day/night, 650 TVL, 2.8-12mm)
DVB-T Receiver
Opticum HD N3
Visual Fault Locator
Worth reading:
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Ethernet media converter and a compatible SFP module
IP CCTV system in low light environment. CMOS cameras have become much more popular than those with CCD sensors. This is due to a significantly lower price. So, who needs the more expensive CCD cameras? The answer is simple - anyone who uses cameras in low light conditions. The increased sensitivity of CCD cameras is the result of the construction of their sensors not burdened with additional circuitry limiting light access... more
How to calculate the depth of field (DOF)? To draw attention of the viewers, photographers and cinematographers often use small DOF, also called shallow focus. This way they can emphasize the subject while downgrading the background or even the foreground. In contrast, for the owners CCTV systems it is desirable to have the entire image sharp, and a large DOF is a must... more
Depth of field determines the distance between the nearest and farthest objects in a scene,
which appear acceptably sharp in the image. It can be calculated using the formula above.