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

No. 12/2024 (March 18, 2024)

Communication with visible light.

Chinese researchers at Nanjing University have developed a communication system using light to provide communication in air, water and space. The project involves the use of different wavelengths: 275 nm, 452 nm, 519 nm and 585 nm depending on the environment. It will form the node of a two-way network called ALCN (All-Light Communication Network). Blue-light communication (BLC) is used for underwater communication, while white-light communication (WLC) facilitates communication on the surface. Ultraviolet (DUVC) and laser diode (LC) communications support air and space communications. The devices feature built-in Ethernet support, allowing both wired and wireless network access and connection of sensors or computers.
The researchers demonstrated a network, linking centers where an IP camera image of 1920 × 1080 resolution at 22 fps was transmitted, with low latency of up to 74 ms and a packet loss rate of 5.8%. The shortest range was achieved in water (12 m) and in air (150 m) with a maximum throughput of 1.5 Mbps. Ultraviolet communication proved to be more efficient reaching 7.8 Mbps, and LC even 10 Mbps. To improve these results, researchers are developing special signal modulation techniques based on wavelength-division multiplexing. Work is also underway on mobile access nodes (e.g., for moving drones).
Light-wave data transmission (LiFi) techniques are widely known, and in 2023 the IEEE organization established a standard for such connections: 802.11bb providing integration with computer networks. Visible light communications as a data carrier is currently being refined by industry, standards groups and government initiatives. It is mainly used in places where traditional Wi-Fi networks may be disrupted or inadequate, such as offices, hospitals and self-service stores. An interesting application could be in public transportation, such as trains and buses, providing Internet connectivity for passengers despite strong electromagnetic interference.

Why are DNS addresses so important for network devices?

A DNS service is used to convert public (external) IP addresses from numeric to domain form. (Domain Name System) service is used. Hence, there is no need to remember the addresses e.g. in the format, but just a much more friendly www.dipolnet.com instead.
Translation of numeric to domain is performed by an appropriate DNS server to which the device sends a translate request. After receiving a response with a numeric address, the host establishes connection with the appropriate server.
Often, when configuring network devices (manually assigning an IP address), the DNS server address is forgotten. Most network devices such as managed switches or access points will work "almost" normally. The problem that may arise in this case is the lack of synchronization. This is due to the fact that the NTP server address is usually given in domain form. The lack of time synchronization results in incorrect time in the logs.

If the DNS server address is not provided in devices such as NVRs, the problems will be much more noticeable. As a rule, they will manifest themselves on the first attempt to connect to the DVR from an external network. This connection will require proper translation of server addresses associated with the implementation of services in the so-called "cloud". Without knowledge of the DNS server, this will not be possible, which in turn will make the connection with the DVR impossible.
Overview of a communication procedure between the client and server using DNS addresses.

1. What is the IP address of www.dipolnet.com? (query DNS server
2. www.dipolnet.com is
3. Hello,! Send me your website.
4. Here is my website.

The AS07STCA-4K ALPSAT meter for RF measurements – one connector for different signal sources.

In addition to the measurement of individual parameters of digital TV signals, which have a significant impact on the correct implementation and operation of RF/SAT systems, one of the main criteria in selecting a meter is the ease of use and functionality. Certainly, a much more convenient device will be a meter that has one input common for DVB-T2 and DVB-S/S2 signals. This solution eliminates the cumbersome switching or rearranging of the cable when measuring directly from the multiswitch. Another important feature is the measurement of RF signals over a very wide range, which eliminates the problem of signal overdriving on individual elements in the system as well as the meter itself.
The screen shoots above show the measurement of DVB-T2 digital terrestrial TV signal and DVB-S2 satellite TV signal (HotBird 13.0E Satellite, Transponder 11508 V). The main parameters are the following: POWER (RF signal level), noise margin, modulation error rate (MER), errors before Viterbi correction (CBER) and after the correction (VBER). All measurements are presented on a single screen. The spectrum distribution analyzer, especially for terrestrial TV, allows you to view strong interfering LTE signals (function for real-time comparison) which can adversely affect the quality of DVB-T2 signal causing interference and interfering with proper reception of terrestrial digital TV.

Quickly configure a monitoring system using a multifunctional CCTV tester.

The process of installing a camera involves positioning it so that all details of interest are in the field of view – for this a preview of the image is required. In addition, in the case of IP cameras, the equipment must be activated, check the correctness of data transmission and power supply, and set the operating parameters. This is often done when power is not yet supplied to the camera point. In such a situation, it is optimal for the installer to use the ALPSAT AS33-IPCX M3214 multifunctional CCTV tester.
The tester can supply power to various devices via power outputs of 2 × 12 VDC/3 A, DC 24 V/2 A, PoE (802.3af/at), and DC 5 V/2 A (USB).
If there are analog cameras to set up, it is possible to use the CVBS HD-ACT application, which will automatically detect what system is connected (HD-TVI, HD-CVI, AHD or CVBS) and allow you to quickly get the image. For IP cameras, there is an IP-Discovery (or One-click video) application that will automatically adjust the subnet to the detected cameras, activate the devices and allow you to quickly start viewing using Rapid Onvif. The program has a history of passwords set, so you do not have to enter them each time. In addition, special versions of manufacturers' applications dedicated to viewing and configuration are installed, including: Hikvision, Dahua, Uniview, Tp-Link, Tiandy, Xmeye, Ezviz.
Preview video from a Hikvision IP camera using Rapid Onvif – Alpsat AS33-IPCX M3214 tester.
In the process of configuring the NVR, for example, in the server room, the tester can be used as a regular monitor by connecting the NVR to the HDMI input.
The device can also help in computer network diagnostics. It can scan the IP network, ports, send ICMP (PING) packets, show the occupancy of IP addresses in the subnet, or with the NET-port Blinking function – it detects the connected port in the switch. In case of failure, it will help analyze the network (connection speed, packet loss, loop detection), and has Cable test function, to detect connection, continuity, maximum transmission speed, and Cable TDR test, to measure length, detect transmission pairs, breaks, cable quality.

Building a house? Think of fiber optics.

When designing or building a house, a lot is said about proper planning of cabling for low-current systems. However, laying the right cables outside the house at an early stage is often forgotten. Usually, apart from power cables, these include twisted-pair cables (e.g. for video intercom, surveillance cameras, intelligent house system elements etc.).
At the stage of construction works, it is also good to think about burying an optical fiber in the ground, which in the future can be used by the Internet provider. From year to year, the optical fiber infrastructure in less urbanized areas is systematically growing. Hundreds of kilometers of overhead networks are built, owned by municipalities as well as by larger and smaller operators. It is very likely that in the nearest future, if not immediately, the fiber optic infrastructure will be built near the house under construction.
Fiber Optic Post: FTTH Distribution Cabinet SSF-1355/295/208Fiber optic cable: Fibertechnic DAC 2J 9/125 G.657A1 2.5 kN
The L79302 ground cable is a cost-effective, reliable and simple solution. Two single-mode fibers in G.657A1 standard will allow to provide Internet and other services.
With the cable buried in the ground, and with a little effort of the service provider, it is possible to , avoid running overhead cable over the plot, which not only affects the overall looks, but also has to be laid on the side of the house, on the external façade or already inside the building. Burying the optical fibre in the ground during the construction phase, and bringing it to the multimedia cabinet, which is the meeting point of all cabling, will pay off in the future.

Power outputs in Hikvision modular IP video door stations.

Following an upgrade of the hardware version of the Hikvision DS-KD8003-IME1(B) G73652 and 2-Wire DS-KD8003Y-IME2 G73646 modular IP video door stations, a 12 VDC power output with a load capacity of up to 0.5 A has been introduced. The solution enables direct powering of the electric door strike from the door station using built-in relays, provided that the electric door strike is powered with DC voltage and current drawn does not exceed 500 mA. If the electric door strike is powered by AC voltage, an additional power supply must be used. When using the power output, we recommend a low-current electric strike, such as Bira XS00 series.
Connection diagram of Bira XS00U electric door strike to Hikvision DS-KD8003-IME1(B) door station.

New products offered by DIPOL

IPTV streamer 4×DVB-T/T2/C-IP sti441C, built-in 2×CI and USB port TERRA
IPTV streamer 4 × DVB-T/T2/C-IP sti441C with built-in 2xCI jack and USB port TERRA R81592 is a device that enables distribution and management of terrestrial and DVB cable TV offerings through a twisted-pair Ethernet (LAN) network. One panel allows conversion of the signal from four multiplexes to an IP stream enabling distribution of TV channels with a total effective bit rate of 200 Mbps. The available output IP stream is fed into the LAN and delivered to end receivers – usually using switches. The multicast technology used in this type of system allows significant savings in network resources.
Single-mode patch cord PC-5572-3 FC/UPC - FC/UPC, simplex, G.657.A2, 5m
Single-mode patchcord PC-5572-5 FC/UPC – FC/UPC, simplex, G.657.A2, 5m L3215572_5 is a 5-meter long section of single-mode fiber optic cable terminated with FC/UPC connectors. The patchcord is manufactured based on single-mode fiber in the G.657.A2 standard. This standard is characterized by a reduced bending radius. This makes the patchcord much less prone to damage and increased attenuation due to excessive bending.
IP NVR: Sunell SN-NVR3832E2 (III) (32 ch, 160 Mbps, AI, 2 × SATA, VGA, HDMI, H.265)
Sunell SN-NVR3832E2 (III) IP NVR (32 channels, 160 Mbps, 2 × SATA, VGA, HDMI, H.265) K26332 is part of the Eco series, composed of reliable and flexible solutions for systems of various sizes. The NVR supports 32 IP channels, enabling the recording of video from IP cameras with a resolution of up to 12 MP. The device supports intelligent image analysis, functions based on artificial intelligence, as well as advanced camera solutions such as ANPR, people counting systems and face recognition. 2 SATA ports enable connection of hard drives with a capacity of up to 12 TB each.

Worth reading

DVB-T2/C in the optical fiber. Fiber optic DVB-T2/C signal transmission providers usually use traditional transmitters and optical receivers, such as the mo418 R82522 transmitter and OD-005P R81760 receiver. Such connections use only separated cables with single-mode fibers, and the division of the signal to deliver it to different locations is carried out using passive optical splitters...>>>more
Transmission of DVB-T2 digital terrestrial television signals from four digital multiplexes over a distance of 20 km
using single-mode optical fiber.
DVB-T/T2(HEVC 10 bit)/C/J.83B/ISDB-T and DVB-S/S2 signal meter AS07STCA-4K with spectrum analyzer and calibration certificate
Alpsat – professional measurement of DVB-T2/C/S2 signals