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

New, super fast laser random number generator.

Scientists have created an entirely new random number generator based on laser light emission. According to normal standards, the design of the new laser is a complete failure. Instead of producing a clear, steady beam, the laser casts a fuzzy patch of light, full of randomly flickering specks. To the team of physicists, however, the laser's disorderly action is its greatest advantage. The chaotic fluctuations of laser light can be translated into 254 trillion random digits per second, more than 100 times faster than other laser-powered random number generators. Random number generators are valuable tools in computer science. They are used to create keys that encrypt data such as passwords and credit card numbers to securely transmit information over the Internet. Computer simulations of complex systems, such as the Earth's climate or the stock market, also require many random numbers to properly capture random events that occur in real life.

The new laser can generate multiple sequences of random numbers at once, similar to throwing multiple dice at once. Fast random number generators help in securing online communications and in advanced computer simulations.

Lasers can generate strings of random numbers due to the small naturally occurring fluctuations in the frequency of light over time. But using a laser beam to generate random numbers is like repeatedly throwing a single dice. To generate multiple strings of random numbers from a single laser at once, physicist Hui Cao of Yale University and her colleagues came up with a new design. In the laser developed by the team, light bounces off mirrors placed at either end of an hourglass-shaped cavity before leaving the device. This irregular shape allows light waves of different frequencies to ricochet and overlap. As a result, when the laser shines on a surface, its light contains an ever-changing pattern of tiny dots that randomly brighten and dim. The brightness at any point in this pattern over time can be translated by a computer into a random series of ones and zeros. Cao and her colleagues pointed the laser at a high-speed camera that measured the intensity of light at 254 points across the beam every billionth of a second or so. The camera tracked the laser light for only a few nanoseconds before its memory filled up, after which the data was sent to a computer to be encoded as 0s and 1s. To work in the real world, such a random number generator would have to be equipped with light detectors that could send brightness measurements to the computer in real time.

The contest to end soon!

Only by Friday, October 1, you can send your works to the ”Engagingly about antennas” – summer photo contest". It is now the twentieth time that we are waiting for your photographs (now also videos), whose main focus is on antennas (in the foreground or background) in any form and shape. The winners will receive attractive prizes from DJi and JBL. will receive attractive prizes from Seagate and SanDisk. You are welcome to join the contest, and read the contest rules before sending works.

TERRA headend in one of Krakow's guesthouses.

The owner of one of the hotels in Krakow decided to upgrade the antenna system. He wanted the system to provide access to all terrestrial DVB-T/T2 channels and selected free-to-air DVB-S/S2 satellite channels from two satellite positions. For this purpose, a 120 cm A9684 satellite dish with a system of two Wide Band LNB GT-WB1 A98222 LNBs was installed on the building roof. The UHF Dipol 44/21-60 Tri Digit A2670 and the VHF DIPOL 7/5-12 A0710 antennas are provided to receive the DVB-T/T2 signal. The signal from the set of antennas is transmitted to the server room, where a set of TERRA channel amplifiers and transmodulators is installed.

How to choose the right outdoor antenna for a GSM repeater and where to place it?

The type of antenna depends both on the amplified band and the distance from the base station. It is essential not to use antennas with too high gain, because it will dramatically increase the probability of amplifier's excitation, which will prevent from proper operation and even interfere with nearby base stations. The higher the gain of the external antenna, the greater the separation between it and the internal antenna.

The order of fibers in optical cables.

Terminating the end of a fiber optic cable with multiple fibers, the installer should pay attention to the appropriate order of the fibers spliced in the distribution frame or installation box. There are several standards addressing that issue, and although there are not general regulations, consistency in this field allows to avoid problems in the event of network maintenance or expansion.

Installing optical cabling, it is worth to implement one of the European standards or the proprietary solutions used by cable manufacturers or large telecommunications operators. The table below shows the most common standards for the layout of fibers in optical distribution frames.

It is worth remembering that the adoption of a specific standard saves time and money in the case of expansion of the optical network. Connecting the next links, the installer does not have to empirically verify the order of the fibers in the existing distribution frames and avoids problems with erroneous connections (especially when the splices are placed in closed patch panels without the possibility of viewing the order of the fibers).

How to power a camera and 12 V microphone using PoE?

Numerous systems are faced with the problem of powering an IP camera via PoE from one UTP cable and another device requiring 12 VDC supply (e.g. an external microphone or an infrared illuminator). This can be done with any PoE (802.3af or PASSIVE) switch and using one output and the PoE Atte ASDC-12-124-HS M18953 stabilizer. The device supplies power to the PoE output and has a 2.1/5.5 12 VDC plug. The maximum current at such output is 1 A at 12 V, however, the power limit available at the PoE output for the switch have to be considered while supplying both devices.

Hikvision video intercom system in the 2-Wire standard.

There is often a need to replace the existing intercom (video) system with a newer one, offering greater functionality and quality. Such an upgrade may require replacement of the cabling, e.g. with twisted pair cables for IP systems. The Hikvision video intercom operating in 2-Wire standard is of help. It has the same functionality , as the 2nd generation Hikvision IP video intercom. Building a compact system involves connecting of monitors (e.g. G74018 DS-KH6320-WTE2) and the main door station module (G73644 DS-KD8003-IME2) to the G74823 DS-KAD706 distributor via a 2-wire bus. The 2-Wire bus allows for both, powering the devices and establishing communication. After connecting the distributor to the LAN network, each device (monitor, door station) is visible in the network under a separate IP address. The iVMS-4200(v3) application is used for configuration. In addition to the basic functionality, i.e. video calls, the system controls opening the wicket and controlling the entrance gate, also can also be controlled with the Hik-Connect application from a smartphone. It can redirect a call to the phone while the tenant is absent and remotely open the wicket or gate.

Sample diagram of a system using the 2-Wire Hikvision system

Designing TV/SAT systems in multi-family buildings. DIPOL offers the MR-9xx and MV-9xx series TERRA mustiswitches for multi-family buildings, designed in accordance with the requirements of TV/SAT systems, ensuring signal reception from two satellites. The solution offered is quite popular, among others on the Polish, British, German and Australian markets. Advanced TERRA multiswitches have been a still highly recognized a solution for large SMATV systems in Poland since 2004. Quality built, stability of parameters and very low failure rate make these multiswitches a product of choice to even the most demanding customers. DIPOL has been selling TERRA products since 1996. The product warranty extended to 4 years has been on offer from March 2013...>>>more

A project made in the SatNet program

Overview of Hikvision video intercom systems