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

New integrated chip paves the way for high-power telecommunications systems.

Despite the tremendous progress that has been made recently in integrated photonic circuits made of lithium niobate, starting from frequency combs to frequency converters and modulators, integrating lasers still remained a major challenge. Long-range telecommunications networks, optical data center interconnects, and microwave photonic systems use lasers to generate the optical carrier, which in turn is used for data transmission. These lasers are usually self-contained components on the printed circuit board of the device with the exception of the modulators for proper light control. This makes the whole device more expensive to manufacture, less efficient and less stable. This barrier has been overcome by researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS), in collaboration with partners Freedom Photonics and HyperLight who have developed the first fully integrated high-power laser based on a lithium niobate chip, paving the way for high-power telecommunications systems, integrated spectrometers, optical remote sensing and efficient frequency conversion for quantum networks.

The researchers used small but powerful distributed feedback lasers in their integrated chip. On the chip, the lasers are located in small wells or grooves carved into lithium niobate and deliver up to 60 mW of optical power in waveguides made on the same platform. The researchers combined the lasers with a 50 GHz lithium niobate electro-optical modulator to build a high-power, high-speed transmitter. Plug and play integration of high-performance lasers will significantly reduce the complexity and power consumption of future communication systems. By combining lithium niobate thin-film devices with high-power lasers using an industry-friendly process, a key step has been taken toward scalable, low-cost, high-performance optical transmitter arrays and networks. Looking ahead, the team intends to increase the power and scalability of the laser for even more applications.

Signal T-2 MINI receiver in a hotel setup – one remote control.

Facing the new DVB-T2 standard, the vast majority of TV systems in hotels will need to be upgraded. The current standard of terrestrial television in most European countries is DVB-T (Digital Video Broadcasting - Terrestrial) with MPEG-4 (H.264/AVC) video coding and Dolby Digital Plus (E-AC-3) audio coding. For several years Europe has been implementing DVB-T2/HEVC, a new standard for terrestrial digital TV broadcasting. Only TV sets capable of decoding so compressed picture and sound are able to correctly receive television programs. A number of DVB-T TV sets now in use are not equipped with a DVB-T2 decoder and can only display images encoded to AVC (also known as H.264 or MPEG-4 part 10), an older video coding standard. After the transition to DVB-T2/HEVC transmission standard, those TVs will no longer "recognize” the broadcast content and an external decoder will have to be purchased.

DIPOL has prepared several solutions for hotel owners whose TV sets are not adapted to the new standard. One of the interesting solutions are DVB-T2 Signal T2-MINI receivers dedicated for hotels, with universal learning remote control.

The video below shows the process of configuring the receiver and remote controller in a hotel system. The settings can be downloaded to a USB memory stick and uploaded to all receivers in the facility.

GSM signal splitting.

In systems with several floors, the signal coming from a GSM repeater has to be split. The GSM splitter is used to distribute the amplified GSM signal to indoor antennas. It operates at frequencies from 800 to 2500 MHz and has an impedance of 50 ohm.

Depending on the specific installation, the following splitter models can be used:

• two-way A6812,
• three-way A6813,
• four-way A6814.

The number and type of splitters depends on output signal strength of GSM repeater. It is the resultant of several factors, among others: signal strength outside the building, gain of outdoor antenna, attenuation of the cables and connectors, and the amplifier gain. The best rule of thumb is to use one two-way splitter in the case of strong signal outside a building, using GSM-305 repeater. For GSM-505 A6775 it is possible to use 2-3 antennas, whereas for the GSM-1205 A6785 repeater, the signal can be branched even to 4-5 antennas. The radius of the amplified signal from each antenna is about 8-9 m (excluding obstacles like walls).

The diagram below shows the installation using the A6813 three-way splitter to connect indoor antennas on each floor of the building.

Fiber optic cable termination in the apartment junction box.

When a fiber optic cable is brought to the apartment junction box its termination is often anything but professional. This is mainly due to three factors: the use of substitute boxes, installers unfamiliar with that type of termination and, finally, savings.

As a professional solution to this problem DIPOL offers new type of mini fiber optic boxes: FTTH DIN L5315. It allows for termination of up to 12 mm in diameter fiber optic cable (typical subscriber cables have a diameter of about 3 mm), with a maximum of 4 fibers. It is usually two-fiber cable terminated with L35522 pigtails plugged into two L4222 adapters. The box is cheap and easy to install.

Is it possible to control the third and fourth door in Hikvision IP video door entry system with one door station?

Depending on the model, Hikvision IP/2-Wire video intercom door stations have up to two relay outputs dedicated to control the wicket and entrance gate. Although an additional DS-K2M061 controller module can be connected to the door stations over the RS-485 bus, this module allows you to replace the second relay output in the door station to increase opening security, rather than adding an additional output. A solution to this problem can be use of relay outputs in the video door entry monitor, e.g. DS-KH6320-WTE1 G74001, provided that the monitor has been provided with additional cabling for such integration. The monitor has two relay outputs that can be set as mono or bistable. Activation of the outputs from the monitor's GUI and configuration is done in the Settings ->Advanced Settings -> Output Settings tab. The outputs can be set for a specific time (1-180 s) or until they are deactivated by the user. After enabling the outputs, an icon will appear in the main window of the monitor, allowing you to enter the control options. The outputs will also be visible from within the Hik-Connect application.

Cable flammability rating – thick smoke emission. Cables, as well as other products used in construction industry are subject to evaluation in terms of their reaction to fire. It is estimated that from 60% to 80% of all fire deaths are caused by poisoning, suffocation or inability to quickly evacuate the place of danger. It is required that the materials used for the furnishings of the building, including wires, cables and other elements associated with the electrical and telecommunications systems, work properly under normal conditions of the building use as well as under emergency conditions. One of the key parameters that determine the fire rating of a cable is its ability not to emit opaque, corrosive and toxic smoke. This is crucial for avoiding intoxication and effective evacuation in case of fire... >>>more