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

Commercial spaceflights.

An American company, Axiom Space, plans to send tourists to the International Space Station (ISS) for 10 days in the second half of 2021. Dubbed Crew Dragon, the spacecraft will carry an Axiom-trained commander and three private astronauts.

The tourists will travel in a new SpaceX Dragon capsule mounted on a Falcon-9 rocket. Elon Musk's company has scheduled a test flight with NASA astronauts to take place before the 2020 summer vacation. The next step after commercial spaceflights will be to build the first hotel in outer space. Once it is in place, tourist flights could take off as often as every two weeks.

The Dragon capsule

NASA has also given Axiom the go-ahead to add new modules to the existing International Space Station (ISS) in mid-2024. This would allow to create a private segment to accommodate arriving tourists. In the future, when the ISS is dismantled, Axiom would be able to detach its segments and convert them into a private space station.

Multiswitch systems based on Wide Band technology.

Using quattro LNBs in multiswitch systems for the reception of channels from two satellite positions (HotBird 13.0E and Astra 19.2E) requires 8 RG-6 coaxial cables. Choosing a Wide Band A98222 LNB instead reduces that number to just four. In contrast to standard quattro devices, Wide Band LNBs have two signal outputs (H polarization/V polarization) and rely on a single local 10.41 GHz oscillator to ensure excellent performance in the entire 290...2340 MHz frequency range.

The Wide-band A98222 LNB cooperates with the Terra SRM-581 R80581 dSCR multiswitch, which has 5 inputs. Two pairs of SAT IF inputs (V1, H1, V2, H2, 290...2340 MHz) should be connected to two Wide-band A98222 LNBs, while the fifth input (of active terrestrial path) is intended for DVB-T, DAB(+) and FM radio signals. In dSCR mode, each of the eight Legacy / dSCR +Terr.TV outputs allows for independent operation of up to 16 SAT dSCR receivers/STBs (EN50607) fed via one coaxial cable, or, in the Legacy mode, can be connected to a legacy SAT TV receiver, in exactly the same way as an output of a Universal LNB or of a standard (legacy) multiswitch.

How to assess camera footage quality?

Pixel density is a common indicator used to assess camera footage quality: the greater the density, the higher the quality of the image and the better the monitoring potential. Image quality can be measured in pixels per object (e.g. a person or face) or pixels per meter (PPM) of a given frame. The basic operational criteria in target monitoring include: detection, recognition, and identification.

To easily verify pixel density, you can us a pixel calculator displayed in the live view panel of Hikvision devices, which shows the width and height of the selected image in pixels. This allows to calculate the total number of pixels per selected area. The feature can be used to verify the number of pixels per license plate or person.

Pixel calcuator - the selected area is marked green. The measurement is shown in a red frame.

Pixel calculators are available, for instance, in Hikvision EasyIP 3.0 cameras and dedicated license plate recognition cameras.

ColorVu cameras in apartment building surveillance systems.

The image below shows an apartment building CCTV system basd on a DVR and IP Hikvision cameras from the EasyIP4.0 ColorVu series. The characteristic feature of the series is that it allows to monitor the scene in color mode around the clock, delivering full color information in all lighting conditions. On the outside, the building has been equipped with eight DS-2CD2047G1-L K03114 compact cameras with a resolution of 4 MP, a 2.8 mm lens, and a viewing angle of 102°. Inside, the system is rounded out with four DS-2CD2347G1-L K00311 ceiling cameras with a resolution of 4 MP, a 2.8 mm lens, and a viewing angle of 109°. Both models come with a white-light illuminator (up to 30 m), which can switch on automatically when the scene gets very dark to ensure a good-quality color image. In most cases, however, where streetlights or internal staircase lights are available, the camera's illuminator stays in the off mode.

Apartment building monitoring with Easy IP 4.0 ColorVu cameras

The distribution of cameras recommended above allows to ensure the accurately identify individuals who attempt to damage the outside of the building (e.g. the walls). The cameras are powered and connected to the DVR via a 16-port PoE switch (N29986). The cameras support H265+, H.265, H.264+, and H.264 standards. With two 4 TB HDDs, such as M89305, H.265 video compression, and continuous recording at 25 fps for all cameras, footage will be stored on HDDs for 14 days.

The most popular access point: Omada EAP.

The TP-Link EAP series provides a secure and flexible wireless network solution that is easy to install and manage. The devices can be easily mounted to a wall or ceiling. WLAN configuration and management have been simplified with a dedicated central management software. Captive portal and automatic RF management make EAP devices ideal for high-density, demanding environments, such as campuses, hotels, shopping centers, and offices.

The TP-LINK EAP225 N2567 access point is a best seller for business applications. It is is a dual-band device operating in 2.4 GHz and 5 GHz bands, at a maximum transmission speed of 450+867 Mbps (simultaneously in 2.4 GHz and 5 GHz bands - 802.11ac standard).

N2567 wireless access point (EAP225, AC1350, 2.4GHz, 5GHz, PoE 802.3af)

Why is fusion splicer calibration important?

Calibration requires that the power and temperature of the generated electric arc should be adjusted to the current environmental conditions. A well-adjusted arc ensures correct splicing, both in terms of attenuation and durability. This means that calibration should always be performed at the outset, before splicing proper, or in the event of a drastic change in conditions (e.g. the sudden drop in temperature when splicing is finished inside the building and moved on to the outside).

The most expensive models of fusion splicers are equipped with pressure and temperature sensors that allow for an automatic calibration in real time. Most popular devices, however, require manual calibration, which will take several minutes. Skipping calibration will not always result in bad splices. However, there is a risk that some, even those indicating low attenuation, will be very weak and unstable mechanically (e.g. if the splicing temperature is too low, they may sometimes crack after an hour).

A Signal Fire AI-8C L5870 fusion splicer

Signal Fire AI-8C L5870 and AI-9 L5875 splicers rely on a popular calibration method: fibers inserted into the splicing chamber are subjected to a series of electric arcs. They melt and the splicer software measures and analyzes how far backward the fiber end faces have moved. Based on the measurement, it determines the appropriate parameters of the electric arc.

In the winter period, installers should pay particular attention to the proper preparation of the splicing equipment before commencing work. A splicer that has spent the night in a car parked outside and has just been brought into a room with room temperature is not ready for immediate use: the fogged camera lens may result in erroneous fiber positioning and auto-focus problems. To avoid such issues, installers should make sure splicers are stored in appropriate temperature conditions.

A multiswitch system in a multi-family building. The most flexible multiswitch installations in multi-story buildings are based on 5-cable systems. The 5-cable bus is split into subnetworks for apartments in each staircase, and then on each floor, by a suitable tap providing signals to a "story" multiswitch. This allows to build a SMATV system with a large potential for further expansion...>>>more

An example of a SMATV system for a multi-family building (4 staircases, 4 floors) - a single satellite position

Vertical mounting system in 19" RACK cabinets