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

Alternative to satellite navigation.

Dutch researchers have developed a positioning system based on cellular networks. It is more stable and more accurate than GPS, especially in urban conditions. The prototype, which was implemented on a specially configured cellular network, achieved an accuracy of 10 centimeters. This new technology is important for implementing a wide range of advanced location-based applications, including autonomous vehicles, quantum communications and next-generation mobile communication systems.

Global Navigation Satellite Systems (GNSS) are being used to navigate and distribute time, essential information for critical infrastructure, mobile communication systems, and new technologies such as autonomous vehicles. Admittedly, satellite navigation can provide centimeter-level accuracy, but it is unreliable. This is particularly evident in cities, where tall buildings block the satellite signal, making positioning inaccurate or failing altogether. This poses a significant problem for autonomous vehicles, for example. In addition, a requirement for the safety of critical infrastructure is the provision of a backup system, which does not exist today.

The researchers have developed a GNSS-independent, ground-based SuperGPS positioning system. Communication with receivers is based on cellular networks. The innovation is the introduction of a highly accurate atomic clock, which makes it possible to transmit positioning messages as well as GPS satellites do, using similar clocks. The connection is made via an existing fiber-optic network, which ensures low latency, less than 1 nanosecond. This allows for accurate navigation and paves the way for the creation of a system for synchronizing time, generated by atomic clocks, to users via telecommunications networks.

Communication with signal receivers is similar to that in cellular networks, however, in an extended frequency range, further broken up into several narrower bands. This increases the reliability of signal transmission in areas with tall buildings. SuperGPS extends the functionality of radio telecommunications networks, which will provide not only connectivity, but also timing and positioning services with unprecedented accuracy and reliability.

DDM function in SFP inserts.

DDM, or Digital Diagnostics Monitoring, is a set of functions that allows you to monitor the operation of fiber SFP modules in network switches. When a DDM-enabled insert is placed in a switch it , gains access to the following insert performance parameters:

Moreover, depending on the implementation of the protocol in the switch itself, it is possible to display messages on the transmission problems and total loss of signal. DDM in connection with SNMP (Simple Network Management Protocol) allows more efficient network management and monitoring of its parameters at physical layer level. It is possible, among other things, due to possibility of defining alarm levels for individual parameters.

Category 5e twisted pair cable with flammability class Cca.

The requirements for using cables with a specific reaction to fire class in a given type of building should be based on a risk analysis made by the installation designer or other national formal and legal documents.

The NETSET U/UTP cat.5e E1415_500 cable complies with the CPR directive and meets the European standard EN 50575, which sets out the requirements for the performance under fire conditions, test methods and evaluation of cables as construction materials.

According to guidelines of the Association of Polish Electrical Engineers guidelines, CPR class Cca cable must be installed outside escape routes in the following buildings:

• residential and community residences,
• tall (25 to 55 m) and high-rise (more than 55 m) above ground level or residential with more than 9 to 18 overground storeys inclusive,
• having rooms intended for the simultaneous presence of more than 50 persons who are not their permanent occupants, and not intended primarily for the use of people with reduced mobility,
• primarily for the use of people with reduced mobility, such as hospitals, nurseries, kindergartens, homes for the elderly,
• commercial buildings.

However, according to guidelines of the Association of Polish Electrical Engineers guidelines, the reaction to fire class of cables and other conductors installed within escape routes should not be less than B2ca-s1b, d1, a1. Therefore DIPOL recommends the NETSET U/UTP cat. 6 B2ca-s1a-d1-a1 E1615_500 cable.

DD 2400 – professional measurement of TV/SAT signals.

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 will be its 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 measurement 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.

Single pass, two-way controlled using the cost-effective DS-K2801 controller.

The diagram below shows a single pass, two-way controlled using the DS-K2801 G75021 cost-effective controller. Readers equipped also with DS-K1107AMK G75662 keypad which operate in the Mifare (13.56 MHz) standard are provided at the input and output. The readers are connected to the DS-K2801 controller via Wiegand communication bus. Such a set-up allows user authorization on entry and exit using card, card and PIN and card or PIN. In addition, authorization can be set in the controller by entering the card number. An XS12R G74232 reversible electric strike is connected to the controller via an emergency exit button K7PEB(Green) G77194. When the exit button is pressed, the circuit connecting the controller to the electric strike is interrupted which causes the door to open. A B-3A G3522 reed switch is mounted on the door, which transmits information about the status of the door to the controller. During the configuration process, the installer assigns user privileges, such as authorization method (e.g. card, PIN), access rights, schedule, etc. so that users can move around the building according to their assigned rights. A history of events is also stored in the controller.

Colored single-mode fiber pigtails. DIPOL offers sets of colored fiber optic pigtails, which allow terminating a fiber optic path in an aesthetically pleasing way and allowing easy identification of individual fibers in a switch, splice tray, etc.>>>more