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

New generation of optical disks.

Scientists from the RMIT University of Melbourne in Australia and the Wuhan Institute of Technology in China have created next-generation disks that far outstrip those currently used in terms of capacity and durability. The new disks will enable secure storage of 10 TB data for over 600 years, instead of only 50 years guaranteed by "long life" optical disks used today. The researchers from China and Australia have developed a method for combining gold particles with glass. Glass is a very durable material whose life span is 1000 years and can be used to store data, but the storage capacity is limited by its inflexibility. A combination of glass and organic material reduces the expected life by half, but dramatically increases efficiency. This hybrid material has been complemented with gold nanoparticles. Gold, like glass, ensures long-term stability and durability. The gold nanoparticles enable recording of information in five dimensions, i.e. in three spatial dimensions plus color and polarization.

A sophisticated combination of gold particles and modified glass
can result in increased durability of optical discs up to 600 years

The huge amounts of data that we generate in the Big Data era (over 2.5 quintillion bytes per day) must be somewhere stored. Data centers consume enormous amounts of energy (about 3 percent of the world's electricity supply) and they mostly use hard drives, which have limited capacity and comparatively short life-span.

The amount of data generated by our civilization increases every year. According to the American Forbes magazine, it currently amounts to approximately 16.3 zettabyte per year (one zettabyte is one trillion of gigabytes). Experts estimate that by 2025 this value will increase 10 times. Storage and processing of such a huge amount of data is a considerable problem and at the same time a challenge for scientists. The new optical disc technology may solve this problem. Thanks to the innovation, it would be possible to extend the lifespan of optical carriers from several dozen to several hundred years.

Any change of a current storage technology poses the question what to do with the data already stored in the "old" system. A complete migration of data to the "new" system is rather uneconomical, because a significant amount of data will never be needed, whereas keeping old devices in operational state is very costly. Does anyone else remember the tape memory? And yet, tape memory had been one of the longest-used medium for storing computer data. Tape drives were introduced in 1951 and began to be replaced from the general use along with the change in the model of computerization in the late 1970s, when the first microcomputers appeared. In 1980, Seagate launched the first 5.25" hard drive, with capacity of 5 MB. The first optical discs designed for recording analog video (Laserdisc) were invented by Philips in the 1960s and introduced to the market in the 1970s. These experiences helped to develop CD-ROMs in the early 1980s (by Philips in cooperation with Sony), still used today.

Four-standard security cameras for every CCTV system.

The n-cam and v-cam universal cameras can be used in every analog CCTV system, with a variety of DVRs. The standard of the output video system is selected with the thumb stick located on the connecting cable. The video system is selected by long pressing (5 s) the thumb stick to the right (HD-TVI), left (CVBS), up (AHD), or down (HD-CVI) - in any doubt refer to the description on the tag.

View of the control box on the connection cables of n-cam and v-cam cameras.
With the thumb stick the user can select the required video system.

TERRA multiswitch system in a multifamily building.

On one of Pomeranian housing developments, MAR-EL company from Elblag, Poland, has installed an SMATV system for 56 users living in a multifamily building. Using one master antenna set, the system distributes satellite signals from two satellites (Hotbird 13.0E and Astra 19.2E), DVB-T (VHF+UHF) and FM signals. The whole system is based on TERRA solutions and devices.

ANR function in Hikvision IP devices.

The video from an IP camera is transmitted to the IP NVR in the form of data stream. In the case of a network failure or bandwidth reduction, the information is irretrievably lost, because the network does not buffer packets and the camera cannot send them again. This is the reason for the increasing popularity of IP cameras with SD/SDHC card recording option. The ANR (Automatic Network Replenishment) solution developed by Hikvision limits the recording on the card placed in the dedicated camera only to the periods of problems with connectivity between the camera and NVR. After the end of the failure, the emergency recordings are automatically transferred to the NVR. So, in the event of interruptions in the transmission, the operator of the system does not need to take any actions to complete the video footage. The function is available in IP NVRs from the K and I series. They have to cooperate with Hikvision IP cameras equipped with memory card slot (marked with F letter in type designation) and suitable microSD card.

In the event of the LAN failure, the ANR function performs automatic video backup onto SD card,
and after the defect has been eliminated, it sends the recording to the NVR automatically

Category of a twisted-pair cable determines its bandwidth.

Twisted-pair (balanced) cables are used to transmit signals in telecommunication systems and computer networks. Currently they are mainly used in analog telephony and Ethernet networks. The most popular twisted-pair cables consist of four pairs. The twisting strongly reduces the influence of external electromagnetic interference and mutual interference between the pairs, called crosstalk.

EIA/TIA standard defines several categories of twisted-pair cables, which determines their suitability for transmission of information. Most new cabling installations use at least CAT 5e cables. Categories of twisted-pair cables along with their main applications:

CAT 5e UTP cable for indoor applications: NETSET U/UTP 5e E1408

How to properly pull out optical fibers from the tube?

Installing fiber optic cabling, the installer should use appropriate tools. There is no place for half measures - the use of tools other than those recommended may result in the risk of damaging optical fibers, which often means serious consequences and financial losses.

Among many activities performed during the installation of fiber optic cables, the most difficult ones include cutting out windows in tubes. The windows are shaved in order to pull out the desired fibers from the tube without disturbing the rest of them, while maintaining the continuity of the tube. Operations of this type are often performed in fiber optic splice closures located on poles carrying multi-fiber trunk cables, where, from a given pole, one or two fibers have to be dropped (as a subscriber link or a branch of the network).

How to use the MSAT-5 L5925 tool
(source: YouTube)

MSAT-5 L5925 Mid-Span Access Tool from Ripley allows easy access to optical fibers in loose buffer tubes with five diameters, from 1.9 mm to 3.0 mm, without risk of damage. It can be safely used for cutting windows in DRAKA universal cables with up to 16 fibers (the tube of the cable with 24 fibers has a larger diameter).

Wide Band SMATV systems - two satellites via four cables. Multiswitch systems with quatro LNBs receiving signals from two satellites (e.g. HotBird 13.0E and Astra 19.2E) have to use 8 coaxial cables (RG-6). A Wide Band LNB (e.g. A98222) has two outputs (H and V polarizations) and the distribution of signals from two satellites requires only four coaxial cables between the LNBs and the suitable multiswitch, reducing by half the number of the cables. With single local oscillators operating at 10.41 GHz, such LNBs provide much wider intermediate frequency band (290...2340 MHz) than conventional (legacy) LNBs... >>>more

An example of SMATV system distributing satellite channels in dSCR/Unicable technology,
along with amplified terrestrial broadcasts