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

Nuclear reactor on the moon.

British aerospace giant Rolls-Royce has confirmed the possibility of receiving funding to develop concepts and implement small nuclear reactors that could provide energy on the Moon. The British space agency has offered £2.9 million ($3.5 million) for research into the use of nuclear power on a lunar base for astronauts.

The manufacturer expects its first car-sized reactor to be ready to be sent to the Moon by 2029. The energy provided by the nuclear power plant is expected to meet the needs of people working on the Silver Globe. With an efficient energy source, much longer exploration missions will be made possible. In the research, Rolls-Royce will receive support from universities of: Bangor, Brighton and Sheffield.

Nuclear power in space is expected to create new skilled jobs throughout the UK. The partnership with Rolls-Royce comes after the UK space agency announced £51 million to develop communications and navigation services for lunar missions as part of the European Space Agency's Moonlight program, which aims to launch a constellation of satellites in orbit around the Moon.

Hybrid dSCR/Unicable multiswitch system.

TERRA's dSCR series of multiswitches are single-cable (Unicable) devices that allow distribution of DVB-S/S2 satellite, DVB-T terrestrial TV and analog/DAB radio signals over a single coaxial cable based on digital channel stacking technology using analog-to-digital converters. Communication between the multiswitch and satellite receivers uses a special protocol, defined in EN50494 (Unicable I) and/or EN50607 (Unicable II), which uses DiSEqC commands to allow independent signal division using a single cable.

The greatest advantage of this solution is the possibility to build branched systems, as in the case of terrestrial television. No star topology is required here. This means that the terrestrial television system can be easily adapted to the reception and distribution of satellite signals (taking into account the limitation of the number of users connected to one multiswitch).

What if the server room is equipped with dSCR/Unicable series multiswitches and the main trunk line is made with fiber optic cable? DIPOL offers optical receivers which allow to build systems based on dSCR/Unicable:

Simple monitoring system with face recognition.

Hikvision's NXI-K and NXI-I series IP DVRs feature face capture and analysis on a specified number of channels. It is possible to create libraries of faces that will later be used to search the recordings. Related actions can also be specified that will be executed in case of a correct or incorrect comparison between a detected face and a face that is in the library, such as triggering a beep in the recorder, an alarm in the monitoring center, sending an e-mail, controlling an alarm output, etc. Faces, already recorded on the DVR or from an external source, can be added to the library. Recordings stored on the DVR, can be easily and quickly searched after pointing to a specific face, on channels on which the face recording and comparison function was active.

The diagram below shows a monitoring system based on the 7608NXI-K2 K22076 DVR. Connected to the DVR are 7 DS-2CD2046G2-I K03141 cameras which are used for general monitoring. One channel is connected to the DS-2CD2646G2-IZS K05313 camera with a resolution of 4 MP, which is used in conjunction with the functionality of the DVR for face analysis and search. Remote access to the system from the external network is provided by the Mercusys MW305R N2931 router.

Fresnel zone.

It is important to realize that the range of a wireless network depends on many factors, some of which we can influence and others are unknown. Fresnel zone is one of the most important concepts appearing in radio subjects you absolutely must be familiar with. It is the area actively involved in the transmission of radio signal energy. The shape of this area in longitudinal section is an ellipse, and in cross-section it is a circle. The radius of this circle varies along the length of the entire radio link and assumes a maximum value in the middle of the distance between the antennas. The first Fresnel zone is the most important, since it is in this zone that almost all the energy of the radio signal is transmitted.

The cross-sectional radius of each Fresnel zone is largest in the center of the zone and decreases to the point of the antenna at each end. The maximum radius of the first Fresnel zone is often useful information. It occurs halfway between the transmitter and receiver.

Objects (hills, trees, buildings, etc.) located in Fresnel zones have a big impact on wave propagation (especially if they are in the first zone). The more of them and the larger they are, the worse the conditions for signal transmission. For links with improved operational reliability, the entire area of the first Fresnel zone should be free of obstructions.

In practice, ensuring the purity of 60% of the 1st Fresnel zone guarantees minimal power loss.

Why there is no login button for Hik-Connect in iVMS-4200.

When installing the Hik-Connect application on a new computer, a problem occurs when the user tries to connect to their account in the Hik-Connect cloud service via iVMS-4200. The button seen below in the image is not displayed, so you cannot enter your login information for this service. This happens when there is no .Net Framework library on the system. It must be downloaded and after installation the computer must be restarted. After the next restart, the mentioned button should appear in the application window.

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 worth using fiber optic meters with an OTDR function? Due to the ever-increasing popularity of fiber optics, the issue of being able to make the right measurements for an optical path is becoming important. Installers often decide to buy the cheapest OTDRs or meters with an OTDR function thinking that they will allow them to perform measurements in a quick and hassle-free manner, and, in case of problems, make a full diagnostics of the link. However, the truth is sometimes painful, and it turns out that in this case "cheap" can be the enemy of "good", but, of course, this is not the rule. However, it is worth knowing that the purchase of the cheapest devices of this type is generally decided by people who do not have practical experience and the required minimum theoretical knowledge. Practice shows that cheaper OTDRs, due to their limited capabilities in presenting results, require more knowledge from the user to interpret them skillfully or to understand why certain information simply cannot be obtained... >>>more