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

No. 39/2013 (Nov. 25, 2013)

Laser origami.

This year's CeBIT was dominated by solutions for 3D printing. A multitude of the exhibitors and many ideas for commercial use of 3D printers have suggested that this is not just a fad, but a kind of trend. The fair held in Hanover and regarded as the biggest event focused on promoting solutions for consumer electronics took place nine months ago. After that time, the initial assumptions have been confirmed - 3D printing is still a very popular subject. What's more - during the short period some alternative concepts emerged.
Technology with a graceful name LaserOrigami well describing its principle and effects, has been developed by a group of researchers at the Hasso Plattner Institute in Germany. This is a completely new approach to creating prototypes, as well as fully functional products, which, in contrast to typical 3D printing methods, can give final results in minutes. The new method hits up selected regions of the material by laser beam, so that it bends under its own weight.
source: www.stefaniemueller.org)

By folding and stretching the material, LaserOrigami can create three-dimensional objects, without the need for manual operations. The heating intensity is controlled by the width of the laser beam - when focused, it cuts the material, when intentionally unfocused, it distributes the laser’s power along a wider path to enable the self-bending. So, the laser beam with modulated width allows both for super-precise cutting and bending elements ​​in a single "printing" process.
(source: www.stefaniemueller.org)

On the left, LaserOrigami fabricated the phone and camera holder in 3 minutes, compared the 240 minutes taken by a 3D printer (the picture in the middle). On the right, the components were cut with a traditional laser and had to be additionally assembled.
Of course, this technique should be considered as a supplement to "traditional" 3D printers - it is suitable for creating rather less complicated objects, but its great advantage is incomparably shorter time of their formation. Will the idea of ​​German scientists find wider application? Perhaps we will learn that in a few months at the next edition of CeBIT.

Why bending radius of an optical fiber is so important?

Optical fiber is a transmission medium using light beams of specific energy and wavelengths. The principle of operation is based on the optical phenomenon of total reflection of light waves at the boundary of two media, the core (9, 50 or 62.5 microns) and cladding (125 microns).

Illustrative drawing showing the leakage of light through the fiber cladding,
caused by exceeding the critical angle of incidence

In practice, reviewing the data sheets of fiber optic cables, it is difficult to find specific values of ​​the critical angles above which the attenuation and risk of damage increase. However, the minimum bending radius of a single fiber depends on its standard, e.g. 30 mm for G.652D fibers, 10 mm for G.657A1 fibers, and only 7.5 mm for G.657A2 fibers used in FTTH systems. Each cable contains one or more fibers, so the installer should not confuse this parameter for a single fiber and for the whole cable. The minimum bending radius of a cable is usually equal to 20x its diameter.

Distribution of television signals via fiber optic cables.

Transmission of television signals via coaxial copper cables at distances exceeding a few hundred meters is not an easy task. Of course, the loss can be compensated by a cascade of amplifiers, but the distribution method has its limitations and the use of active devices increases the cost of the entire system. Due to the fact that the cost of typical fiber-optic cables with four fibers is comparable with the price level of high-quality copper cables, it is worth to consider application of the optical medium. Its capability of transmission over very long distances and full electrical isolation between nodes make the main advantages of fiber optic systems.
The following diagram shows the idea of ​​distributing digital DVB-T signals in a shared antenna installation (MATV system) based on TERRA devices. The aim of the project was to distribute the DVB-T signals to four buildings located approximately 500 meters from the center point. This solution is ideal for cable operators and ISPs having their own fiber-optic infrastructure in some area and wanting to expand their range of services with television. It can be free-to-air DVB-T broadcasts (the users will not have to worry about installing individual antennas), or pay-TV packages, similar to those offered by traditional cable TV operators.
Optical Node  TERRA OD-120Four-channel Amplifier: Terra at440 (UHF, DVB-T, AGC) TV Optical Transmitter: TERRA mo418 4D31 (1x6dBm, 1310nm)Optical Splitter: Terra so414 (1x4)DIN Rail Power Supply DR-60-12 (12VDC/4.5A, for Terra at/mt/ma modules)
Distribution digital DVB-T signals (4 multiplexes) via single-mode fibers
to four buildings
The DVB-T signals are fed into the system through modern, four-channel amplifier TERRA at440 R82511 with digital interface (buttons and display located on the front panel). TV optical transmitter TERRA mo418 4D31 R82522 converts input electrical signals within 47-2400 MHz range into optical signal. Another module, mounted on the same R82538 DIN rail, is optical splitter TERRA so414 R82527 used for splitting the optical signal from the output of the optical transmitter into four optical paths. The amplifier and optical transmitter are powered from the DR-60-12 R82532 power supply (12 VDC / 4.5 A).
The reverse conversion from the optical to electrical medium is carried out by optical nodes TERRA OD-120 R81724 located in the buildings.

How to power IP cameras - PoE options.

Professional IP cameras can be powered using PoE IEEE 802.3af standard. The standard allows for connecting a camera only via one UTP cable that provides power to the camera and transmits the surveillance data. The IEEE 802.3af standard limits the power to 15.4 W (min. 44 V * max. 0.35 A). The power can be transmitted via twisted pair cable of category 3 or higher. The power transmission is implemented through the application of pairs unused for data transmission ("blue" and "brown").
Examples of practical implementation of PoE in IP CCTV systems:
  • 48 VDC power supply with appropriate POE adapter, e.g. M1894 (48V/1.25A) with N9206 PoE adapter. In the case of powering a larger number cameras, the optimal solution can be the application of 16-port PoE panel M1611 and suitable power supply.
16-port Passive PoE Panel: POEP1611B (with 48V/120W power supply)
16-port PoE adapter
  • switch with PoE option - depending on the model the PoE function is available in all or some selected ports
PoE Switch: TP-LINK TL-SF1008P (8x10/100Mb/s incl. 4xPoE)
PoE Switch: TP-LINK TL-SF1008P (8x10/100Mb/s incl. 4xPoE)
Managed Switch: TP-LINK TL-SG3424P JetStream (24xGbE-PoE, 4xSFP)
  • PoE power supply - for one camera, e.g. PSA16U-480 M1890
PoE Power Supply PSA16U-480
PoE Power Supply PSA16U-480

Sound recording in CCTV systems.

In most cases, D1 analog cameras are not equipped with built-in microphones, so for applications requiring sound recording they should be fitted with additional audio modules, such as M1916. The size of such modules is so small that they can be easily placed in outdoor housings, such as M5405. The modules require 12 VDC supplying voltage and their outputs have to be connected to audio inputs of DVRs (typically RCA type).
SMPS AC/DC Adapter: 5VDC/2.3A (2.1/5.5 jack)Outdoor Camera Housing: Marathon MH-805/12 (slide-type)Day/Night Box Camera: u-cam 650 (650TVL, Sony Effio-E, ICR, D-WDR, 0.03 lx)Audio Module: MP-6/D (microphone w/ balanced output) CCTV Network DVR: Ultimax 1308 (8ch-25fps-H.264-HDMI)
Connection of audio module to a DVR.
The sound is provided to the monitor via HDMI output.
All ULTIMAX DVRs are capable of sound recording. Depending on the model, they can monitor/record one to four audio channels. The audio functionality can be configured in such a way that it is possible to listen to the sound both in live view and playback of archival recordings. An important feature of ULTIMAX DVRs is HDMI output that can transmit video and audio to a monitor equipped with speakers, limiting the number of cables.

How to transmit HDMI signals over long distances?

The Signal-HD H3608 HDMI to fiber optic converter allows for long-range (up to 20 km) transmission of HDMI signal (also in HD quality) via a single-mode fiber. Simultaneously, it ensures remote control of the HDMI source device by converting and transmitting commands from its IR remote control.
Transmission of HDMI signal using Signal-HD H3608 converter and optical link
The kit is ideal for connecting a satellite receiver, media player, Blu-ray/DVD player, PC etc. to a remote monitor/television (or to a number of monitors/TVs - the HDMI signal retrieved from the optical signal can be split by HDMI splitters, e.g. H3214). It is also possible to use the converter at universities e.g. in order to send signals from remote laptops to projectors.

New products offered by DIPOL:
Mobile GSM/DCS/3G Antenna (3m cable, FME socket)
TV Optical Transmitter: TERRA mo428 4D31 (2x6dBm, 1310nm)
Terrestrial & SAT TV Amplifier (w. return path): Terra HSA-001R6
Mobile GSM/DCS/3G Antenna
(3m cable, FME socket)
TV Optical Transmitter
(2x6dBm, 1310nm)
TERRA mo428 4D31
Building Amplifier
Terra MA-049L (FM-BIII-UHF, 34dB)
from DIPOL:
Snapshots from China Public Security Expo, the biggest security fair in Asia.

Worth reading:
Optical fibers in IP CCTV systems. Twisted pair cables used in IP CCTV systems limit the transmission distance without signal regeneration to 100-meter runs. In many situations, this is a significant limitation which forces the application of additional equipment. A definitely better option is to use fiber optic transmission means, which become increasingly popular in digital and analog video surveillance systems.... more
IP CCTV system using a universal multimode cable
Red line - UTP cable runs up to 100 m
Blue line - MM cable, runs up to 2 km